Muscular contractions characterized by increase in tension without change in length.
A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
A state arrived at through prolonged and strong contraction of a muscle. Studies in athletes during prolonged submaximal exercise have shown that muscle fatigue increases in almost direct proportion to the rate of muscle glycogen depletion. Muscle fatigue in short-term maximal exercise is associated with oxygen lack and an increased level of blood and muscle lactic acid, and an accompanying increase in hydrogen-ion concentration in the exercised muscle.
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
Recording of the changes in electric potential of muscle by means of surface or needle electrodes.
Muscle contraction with negligible change in the force of contraction but shortening of the distance between the origin and insertion.
The rotational force about an axis that is equal to the product of a force times the distance from the axis where the force is applied.
Region of the body immediately surrounding and including the ELBOW JOINT.
The spread of response if stimulation is prolonged. (Campbell's Psychiatric Dictionary, 8th ed.)
Contractile tissue that produces movement in animals.
Use of electric potential or currents to elicit biological responses.
Large, multinucleate single cells, either cylindrical or prismatic in shape, that form the basic unit of SKELETAL MUSCLE. They consist of MYOFIBRILS enclosed within and attached to the SARCOLEMMA. They are derived from the fusion of skeletal myoblasts (MYOBLASTS, SKELETAL) into a syncytium, followed by differentiation.
A region of the lower extremity immediately surrounding and including the KNEE JOINT.
Contractile activity of the MYOCARDIUM.
Neurons which activate MUSCLE CELLS.
The amount of force generated by MUSCLE CONTRACTION. Muscle strength can be measured during isometric, isotonic, or isokinetic contraction, either manually or using a device such as a MUSCLE STRENGTH DYNAMOMETER.
Contraction of the UTERINE MUSCLE.
The repeating contractile units of the MYOFIBRIL, delimited by Z bands along its length.
Processes and properties of the MUSCULOSKELETAL SYSTEM.
That phase of a muscle twitch during which a muscle returns to a resting position.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
The time span between the beginning of physical activity by an individual and the termination because of exhaustion.
Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)
A diverse superfamily of proteins that function as translocating proteins. They share the common characteristics of being able to bind ACTINS and hydrolyze MgATP. Myosins generally consist of heavy chains which are involved in locomotion, and light chains which are involved in regulation. Within the structure of myosin heavy chain are three domains: the head, the neck and the tail. The head region of the heavy chain contains the actin binding domain and MgATPase domain which provides energy for locomotion. The neck region is involved in binding the light-chains. The tail region provides the anchoring point that maintains the position of the heavy chain. The superfamily of myosins is organized into structural classes based upon the type and arrangement of the subunits they contain.
A powerful flexor of the thigh at the hip joint (psoas major) and a weak flexor of the trunk and lumbar spinal column (psoas minor). Psoas is derived from the Greek "psoa", the plural meaning "muscles of the loin". It is a common site of infection manifesting as abscess (PSOAS ABSCESS). The psoas muscles and their fibers are also used frequently in experiments in muscle physiology.
Voluntary activity without external compulsion.
The quadriceps femoris. A collective name of the four-headed skeletal muscle of the thigh, comprised of the rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis.
Elements of limited time intervals, contributing to particular results or situations.
Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.
Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A species of the family Ranidae occurring in a wide variety of habitats from within the Arctic Circle to South Africa, Australia, etc.
The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.
The joint that is formed by the inferior articular and malleolar articular surfaces of the TIBIA; the malleolar articular surface of the FIBULA; and the medial malleolar, lateral malleolar, and superior surfaces of the TALUS.
The recording of muscular movements. The apparatus is called a myograph, the record or tracing, a myogram. (From Stedman, 25th ed)
An endogenous substance found mainly in skeletal muscle of vertebrates. It has been tried in the treatment of cardiac disorders and has been added to cardioplegic solutions. (Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Englewood, CO, 1996)
The portion of the leg in humans and other animals found between the HIP and KNEE.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
Resistance and recovery from distortion of shape.
Skeletal muscle structures that function as the MECHANORECEPTORS responsible for the stretch or myotactic reflex (REFLEX, STRETCH). They are composed of a bundle of encapsulated SKELETAL MUSCLE FIBERS, i.e., the intrafusal fibers (nuclear bag 1 fibers, nuclear bag 2 fibers, and nuclear chain fibers) innervated by SENSORY NEURONS.
An edible species of the family Ranidae, occurring in Europe and used extensively in biomedical research. Commonly referred to as "edible frog".
The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
The nonstriated involuntary muscle tissue of blood vessels.
The inferior part of the lower extremity between the KNEE and the ANKLE.
An alpha-1 adrenergic agonist used as a mydriatic, nasal decongestant, and cardiotonic agent.
The electrical response evoked in a muscle or motor nerve by electrical or magnetic stimulation. Common methods of stimulation are by transcranial electrical and TRANSCRANIAL MAGNETIC STIMULATION. It is often used for monitoring during neurosurgery.
A device that measures MUSCLE STRENGTH during muscle contraction, such as gripping, pushing, and pulling. It is used to evaluate the health status of muscle in sports medicine or physical therapy.
Four or five slender jointed digits in humans and primates, attached to each HAND.
A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.
Fibrous bands or cords of CONNECTIVE TISSUE at the ends of SKELETAL MUSCLE FIBERS that serve to attach the MUSCLES to bones and other structures.
An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.
The distal part of the arm beyond the wrist in humans and primates, that includes the palm, fingers, and thumb.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.
Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex.
Part of the arm in humans and primates extending from the ELBOW to the WRIST.
Force exerted when gripping or grasping.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
The first digit on the radial side of the hand which in humans lies opposite the other four.
A synovial hinge connection formed between the bones of the FEMUR; TIBIA; and PATELLA.
A hinge joint connecting the FOREARM to the ARM.
The relationship between the dose of an administered drug and the response of the organism to the drug.
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
The superior part of the upper extremity between the SHOULDER and the ELBOW.
Reflex contraction of a muscle in response to stretching, which stimulates muscle proprioceptors.
The physical state of supporting an applied load. This often refers to the weight-bearing bones or joints that support the body's weight, especially those in the spine, hip, knee, and foot.
A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.
The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)
A nerve originating in the lumbar spinal cord (usually L2 to L4) and traveling through the lumbar plexus to provide motor innervation to extensors of the thigh and sensory innervation to parts of the thigh, lower leg, and foot, and to the hip and knee joints.
Drugs used to cause constriction of the blood vessels.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The portion of the descending aorta proceeding from the arch of the aorta and extending to the DIAPHRAGM, eventually connecting to the ABDOMINAL AORTA.
The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.
The smaller subunits of MYOSINS that bind near the head groups of MYOSIN HEAVY CHAINS. The myosin light chains have a molecular weight of about 20 KDa and there are usually one essential and one regulatory pair of light chains associated with each heavy chain. Many myosin light chains that bind calcium are considered "calmodulin-like" proteins.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
A masticatory muscle whose action is closing the jaws.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
A mechanism of communicating one's own sensory system information about a task, movement or skill.
Either of two extremities of four-footed non-primate land animals. It usually consists of a FEMUR; TIBIA; and FIBULA; tarsals; METATARSALS; and TOES. (From Storer et al., General Zoology, 6th ed, p73)
The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.
An adrenergic-beta-2 antagonist that has been used for cardiac arrhythmia, angina pectoris, hypertension, glaucoma, and as an antithrombotic.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
A technique that involves the use of electrical coils on the head to generate a brief magnetic field which reaches the CEREBRAL CORTEX. It is coupled with ELECTROMYOGRAPHY response detection to assess cortical excitability by the threshold required to induce MOTOR EVOKED POTENTIALS. This method is also used for BRAIN MAPPING, to study NEUROPHYSIOLOGY, and as a substitute for ELECTROCONVULSIVE THERAPY for treating DEPRESSION. Induction of SEIZURES limits its clinical usage.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
The chemical reactions involved in the production and utilization of various forms of energy in cells.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
The distal extremity of the leg in vertebrates, consisting of the tarsus (ANKLE); METATARSUS; phalanges; and the soft tissues surrounding these bones.
A vague complaint of debility, fatigue, or exhaustion attributable to weakness of various muscles. The weakness can be characterized as subacute or chronic, often progressive, and is a manifestation of many muscle and neuromuscular diseases. (From Wyngaarden et al., Cecil Textbook of Medicine, 19th ed, p2251)
An amino acid that occurs in vertebrate tissues and in urine. In muscle tissue, creatine generally occurs as phosphocreatine. Creatine is excreted as CREATININE in the urine.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
A highly variable species of the family Ranidae in Canada, the United States and Central America. It is the most widely used Anuran in biomedical research.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
The region of the lower limb between the FOOT and the LEG.
The detailed examination of observable activity or behavior associated with the execution or completion of a required function or unit of work.
Freedom from activity.
Cyclical movement of a body part that can represent either a physiologic process or a manifestation of disease. Intention or action tremor, a common manifestation of CEREBELLAR DISEASES, is aggravated by movement. In contrast, resting tremor is maximal when there is no attempt at voluntary movement, and occurs as a relatively frequent manifestation of PARKINSON DISEASE.
Isopropyl analog of EPINEPHRINE; beta-sympathomimetic that acts on the heart, bronchi, skeletal muscle, alimentary tract, etc. It is used mainly as bronchodilator and heart stimulant.
The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.
The hollow, muscular organ that maintains the circulation of the blood.
The position or attitude of the body.
The distance and direction to which a bone joint can be extended. Range of motion is a function of the condition of the joints, muscles, and connective tissues involved. Joint flexibility can be improved through appropriate MUSCLE STRETCHING EXERCISES.
The rate dynamics in chemical or physical systems.
A continuing periodic change in displacement with respect to a fixed reference. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The flow of BLOOD through or around an organ or region of the body.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Inorganic salts of phosphoric acid.
The state of activity or tension of a muscle beyond that related to its physical properties, that is, its active resistance to stretch. In skeletal muscle, tonus is dependent upon efferent innervation. (Stedman, 25th ed)
Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.
The processes of heating and cooling that an organism uses to control its temperature.
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.
The motor activity of the GASTROINTESTINAL TRACT.
Adenosine 5'-(trihydrogen diphosphate). An adenine nucleotide containing two phosphate groups esterified to the sugar moiety at the 5'-position.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
A stable prostaglandin endoperoxide analog which serves as a thromboxane mimetic. Its actions include mimicking the hydro-osmotic effect of VASOPRESSIN and activation of TYPE C PHOSPHOLIPASES. (From J Pharmacol Exp Ther 1983;224(1): 108-117; Biochem J 1984;222(1):103-110)
A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.
An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.
The region of the lower limb in animals, extending from the gluteal region to the FOOT, and including the BUTTOCKS; HIP; and LEG.
Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
A potent vasodilator agent with calcium antagonistic action. It is a useful anti-anginal agent that also lowers blood pressure.
A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
A methylxanthine naturally occurring in some beverages and also used as a pharmacological agent. Caffeine's most notable pharmacological effect is as a central nervous system stimulant, increasing alertness and producing agitation. It also relaxes SMOOTH MUSCLE, stimulates CARDIAC MUSCLE, stimulates DIURESIS, and appears to be useful in the treatment of some types of headache. Several cellular actions of caffeine have been observed, but it is not entirely clear how each contributes to its pharmacological profile. Among the most important are inhibition of cyclic nucleotide PHOSPHODIESTERASES, antagonism of ADENOSINE RECEPTORS, and modulation of intracellular calcium handling.
A protein complex of actin and MYOSINS occurring in muscle. It is the essential contractile substance of muscle.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
The vessels carrying blood away from the heart.
The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
The excretory duct of the testes that carries SPERMATOZOA. It rises from the SCROTUM and joins the SEMINAL VESICLES to form the ejaculatory duct.
A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.
A group of intracellular-signaling serine threonine kinases that bind to RHO GTP-BINDING PROTEINS. They were originally found to mediate the effects of rhoA GTP-BINDING PROTEIN on the formation of STRESS FIBERS and FOCAL ADHESIONS. Rho-associated kinases have specificity for a variety of substrates including MYOSIN-LIGHT-CHAIN PHOSPHATASE and LIM KINASES.
The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.
The physical activity of a human or an animal as a behavioral phenomenon.
A non-steroidal anti-inflammatory agent (NSAID) that inhibits the enzyme cyclooxygenase necessary for the formation of prostaglandins and other autacoids. It also inhibits the motility of polymorphonuclear leukocytes.
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
The smooth muscle coat of the uterus, which forms the main mass of the organ.
Drugs used to cause dilation of the blood vessels.
A partial or complete return to the normal or proper physiologic activity of an organ or part following disease or trauma.
An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.
Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.
Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.
Skeletal muscle fibers characterized by their expression of the Type II MYOSIN HEAVY CHAIN isoforms which have high ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment. Several fast types have been identified.
The artery formed by the union of the right and left vertebral arteries; it runs from the lower to the upper border of the pons, where it bifurcates into the two posterior cerebral arteries.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Drugs that selectively bind to and activate alpha adrenergic receptors.
A calcium channel blocker that is a class IV anti-arrhythmia agent.
The musculofibrous partition that separates the THORACIC CAVITY from the ABDOMINAL CAVITY. Contraction of the diaphragm increases the volume of the thoracic cavity aiding INHALATION.
An inhibitor of nitric oxide synthetase which has been shown to prevent glutamate toxicity. Nitroarginine has been experimentally tested for its ability to prevent ammonia toxicity and ammonia-induced alterations in brain energy and ammonia metabolites. (Neurochem Res 1995:200(4):451-6)
A 21-amino acid peptide produced in a variety of tissues including endothelial and vascular smooth-muscle cells, neurons and astrocytes in the central nervous system, and endometrial cells. It acts as a modulator of vasomotor tone, cell proliferation, and hormone production. (N Eng J Med 1995;333(6):356-63)
The main trunk of the systemic arteries.

Evidence for beta3-adrenoceptor subtypes in relaxation of the human urinary bladder detrusor: analysis by molecular biological and pharmacological methods. (1/2703)

The purpose of the present study was to confirm the presence of beta3-adrenoceptor subtype in the relaxation of human urinary bladder detrusor tissue by reverse transcription-polymerase chain reaction (PCR); direct sequencing of the PCR product, in situ hybridization; and isometric contraction. Using reverse transcription-PCR, the mRNAs of three receptor subtypes (beta1, beta2, and beta3) were expressed in the human urinary bladder detrusor tissue. Direct sequencing of the PCR product of the above beta3-adrenoceptor revealed no mutation in the amplified regions. In situ hybridization with digoxygenin-labeled oligonucleotide probe revealed the presence of the mRNA of beta3-adrenoceptor subtype in the smooth muscle of the urinary bladder. The relaxant effects of isoproterenol (a nonselective beta-adrenoceptor agonist); ZD7114, BRL37344, and CGP12177A (putative selective beta3-adrenoceptor agonists); and SR59230A (a putative selective beta3-adrenoceptor antagonist) were tested using an isometric contraction technique. Isoproterenol in either the presence or absence of both atenolol (a beta1-adrenoceptor-selective antagonist) and butoxamine (a beta2-adrenoceptor-selective antagonist) revealed a relaxant effect on the carbachol-induced contraction of the human urinary bladder detrusor. Both BRL37344 and CGP12177A also revealed relaxant effects on the human urinary bladder detrusor, but ZD7114 did not elicit any relaxation. These results suggest that beta3-adrenoceptor may have some role in urine storage in the human urinary bladder.  (+info)

Optimality of position commands to horizontal eye muscles: A test of the minimum-norm rule. (2/2703)

Six muscles control the position of the eye, which has three degrees of freedom. Daunicht proposed an optimization rule for solving this redundancy problem, whereby small changes in eye position are maintained by the minimum possible change in motor commands to the eye (the minimum-norm rule). The present study sought to test this proposal for the simplified one-dimensional case of small changes in conjugate eye position in the horizontal plane. Assuming such changes involve only the horizontal recti, Daunicht's hypothesis predicts reciprocal innervation with the size of the change in command matched to the strength of the recipient muscle at every starting position of the eye. If the motor command to a muscle is interpreted as the summed firing rate of its oculomotor neuron (OMN) pool, the minimum-norm prediction can be tested by comparing OMN firing rates with forces in the horizontal recti. The comparison showed 1) for the OMN firing rates given by Van Gisbergen and Van Opstal and the muscle forces given by Robinson, there was good agreement between the minimum-norm prediction and experimental observation over about a +/-30 degrees range of eye positions. This fit was robust with respect to variations in muscle stiffness and in methods of calculating muscle innervation. 2) Other data sets gave different estimates for the range of eye-positions within which the minimum-norm prediction held. The main sources of variation appeared to be disagreement about the proportion of OMNs with very low firing-rate thresholds (i.e., less than approximately 35 degrees in the OFF direction) and uncertainty about eye-muscle behavior for extreme (>30 degrees ) positions of the eye. 3) For all data sets, the range of eye positions over which the minimum-norm rule applied was determined by the pattern of motor-unit recruitment inferred for those data. It corresponded to the range of eye positions over which the size principle of recruitment was obeyed by both agonist and antagonist muscles. It is argued that the current best estimate of the oculomotor range over which minimum-norm control could be used for conjugate horizontal eye position is approximately +/-30 degrees. The uncertainty associated with this estimate would be reduced by obtaining unbiased samples of OMN firing rates. Minimum-norm control may result from reduction of the image movement produced by noise in OMN firing rates.  (+info)

Nonlinear tension summation of different combinations of motor units in the anesthetized cat peroneus longus muscle. (3/2703)

The purpose of this study was to examine the linearity of summation of the forces produced by the stimulation of different combinations of type identified motor units (MUs) in the cat peroneus longus muscle (PL) under isometric conditions. The muscle was fixed at its twitch optimal length, and the tension produced by the single MU was recorded during 24- and 72-Hz stimulation. The summation analysis was first carried out for MUs belonging to the same functional group, and then different combinations of fast fatigable (FF) MUs were added to the nonfatigable slow (S) and fatigue resistant (FR) group. The tension resulting from the combined stimulation of increasing numbers of MUs (measured tension) was evaluated and compared with the linearly predicted value, calculated by adding algebraically the tension produced by the individual MUs assembled in the combination (calculated tension). Tension summation displayed deviations from linearity. S and FR MUs mainly showed marked more than linear summation; FF MUs yielded either more or less than linear summation; and, when the FF units were recruited after the S and FR MUs, less than linear summation always occurred. The magnitude of the nonlinear summation appeared stimulus frequency dependent for the fatigable FF and FI group. The relationship between measured tension and calculated tension for each MU combination was examined, and linear regression lines were fitted to each set of data. The high correlation coefficients and the different slope values for the different MU-type combinations suggested that the nonlinear summation was MU-type specific. The mechanisms of nonlinear summations are discussed by considering the consequences of internal shortening and thus the mechanical interactions among MUs and shifts in muscle fiber length to a more or less advantageous portion of single MU length-tension curves.  (+info)

Modulation of the thermoregulatory sweating response to mild hyperthermia during activation of the muscle metaboreflex in humans. (4/2703)

1. To investigate the effect of the muscle metaboreflex on the thermoregulatory sweating response in humans, eight healthy male subjects performed sustained isometric handgrip exercise in an environmental chamber (35 C and 50 % relative humidity) at 30 or 45 % maximal voluntary contraction (MVC), at the end of which the blood circulation to the forearm was occluded for 120 s. The environmental conditions were such as to produce sweating by increase in skin temperature without a marked change in oesophageal temperature. 2. During circulatory occlusion after handgrip exercise at 30 % MVC for 120 s or at 45 % MVC for 60 s, the sweating rate (SR) on the chest and forearm (hairy regions), and the mean arterial blood pressure were significantly above baseline values (P < 0.05). There were no changes from baseline values in the oesophageal temperature, mean skin temperature, or SR on the palm (hairless regions). 3. During the occlusion after handgrip exercise at 30 % MVC for 60 s and during the occlusion alone, none of the measured parameters differed from baseline values. 4. It is concluded that, under mildly hyperthermic conditions, the thermoregulatory sweating response on the hairy regions is modulated by afferent signals from muscle metaboreceptors.  (+info)

Shortening of muscle relaxation time after creatine loading. (5/2703)

The effect of creatine (Cr) supplementation on muscle isometric torque generation and relaxation was investigated in healthy male volunteers. Maximal torque (Tmax), contraction time (CT) from 0.25 to 0.75 of Tmax, and relaxation time (RT) from 0.75 to 0.25 of Tmax were measured during 12 maximal isometric 3-s elbow flexions interspersed by 10-s rest intervals. Between the pretest and the posttest, subjects ingested Cr monohydrate (4 x 5 g/day; n = 8) or placebo (n = 8) for 5 days. Pretest Tmax, CT, and RT were similar in Cr and placebo groups. Also in the posttest, Tmax and CT were similar between groups. However, posttest RT was decreased consistently by approximately 20% (P < 0.05) in the Cr group from the first to the last of the 12 contractions. In addition, the mean decrease in RT after Cr loading was positively correlated with pretest RT (r = 0.82). It is concluded that Cr loading facilitates the rate of muscle relaxation during brief isometric muscle contractions without affecting torque production.  (+info)

Modulation of temperature-induced tone by vasoconstrictor agents. (6/2703)

One of the primary cardiovascular adjustments to hyperthermia is a sympathetically mediated increase in vascular resistance in the viscera. Nonneural factors such as a change in vascular tone or reactivity may also contribute to this response. Therefore, the aim of this study was to determine whether vascular smooth muscle tone is altered during heating to physiologically relevant temperatures >37 degrees C. Gradually increasing bath temperature from 37 degrees C (normothermia) to 43 degrees C (severe hyperthermia) produced graded contractions in vascular ring segments from rat mesenteric arteries and thoracic aortae. In untreated rings these contractions were relatively small, whereas hyperthermia elicited near-maximal increases in tension when rings were constricted with phenylephrine or KCl before heating. In phenylephrine-treated mesenteric arterial rings, the contractile responses to heating were markedly attenuated by the Ca2+ channel antagonists nifedipine and diltiazem. Diltiazem also blocked the contractile responses to heating in thoracic aortic rings. These results demonstrate that hyperthermia has a limited effect on tension generation in rat vascular smooth muscle in the absence of vascular tone. However, in the presence of agonist-induced tone, tension generation during heating is markedly enhanced and dependent on extracellular Ca2+. In conclusion, these data suggest that local regulation of vascular tone can contribute to the hemodynamic adjustments to hyperthermia.  (+info)

Alterations in diaphragm contractility after nandrolone administration: an analysis of potential mechanisms. (7/2703)

The aim of this study was to evaluate the potential mechanisms underlying the improved contractility of the diaphragm (Dia) in adult intact male hamsters after nandrolone (Nan) administration, given subcutaneously over 4 wk via a controlled-release capsule (initial dose: 4.5 mg. kg-1. day-1; with weight gain, final dose: 2.7 mg. kg-1. day-1). Control (Ctl) animals received blank capsules. Isometric contractile properties of the Dia were determined in vitro after 4 wk. The maximum velocity of unloaded shortening (Vo) was determined in vitro by means of the slack test. Dia fibers were classified histochemically on the basis of myofibrillar ATPase staining and fiber cross-sectional area (CSA), and the relative interstitial space was quantitated. Ca2+-activated myosin ATPase activity was determined by quantitative histochemistry in individual diaphragm fibers. Myosin heavy chain (MHC) isoforms were identified electrophoretically, and their proportions were determined by using scanning densitometry. Peak twitch and tetanic forces, as well as Vo, were significantly greater in Nan animals compared with Ctl. The proportion of type IIa Dia fibers was significantly increased in Nan animals. Nan increased the CSA of all fiber types (26-47%), whereas the relative interstitial space decreased. The relative contribution of fiber types to total costal Dia area was preserved between the groups. Proportions of MHC isoforms were similar between the groups. There was a tendency for increased expression of MHC2B with Nan. Ca2+-activated myosin ATPase activity was increased 35-39% in all fiber types in Nan animals. We conclude that, after Nan administration, the increase in Dia specific force results from the relatively greater Dia CSA occupied by hypertrophied muscle fibers, whereas the increased ATPase activity promotes a higher rate of cross-bridge turnover and thus increased Vo. We speculate that Nan in supraphysiological doses have the potential to offset or ameliorate conditions associated with enhanced proteolysis and disordered protein turnover.  (+info)

Peptide toxin blockers of voltage-sensitive K+ channels: inotropic effects on diaphragm. (8/2703)

Agents that block many types of K+ channels (e.g., the aminopyridines) have substantial inotropic effects in skeletal muscle. Specific blockers of ATP-sensitive and Ca2+-activated K+ channels, on the other hand, do not, or minimally, alter the force of nonfatigued muscle, consistent with a predominant role for voltage-gated K+ channels in regulating muscle force. To test this more directly, we examined the effects of peptide toxins, which in other tissues specifically block voltage-gated K+ channels, on rat diaphragm in vitro. Twitch force was increased in response to alpha-, beta-, and gamma-dendrotoxin and tityustoxin Kalpha (17 +/- 6, 22 +/- 5, 42 +/- 14, and 13 +/- 5%; P < 0.05, < 0.01, < 0.05, < 0.05, respectively) but not in response to delta-dendrotoxin or BSA (in which toxins were dissolved). Force during 20-Hz stimulation was also increased significantly by alpha-, beta-, and gamma-dendrotoxin and tityustoxin Kalpha. Among agents, increases in twitch force correlated with the degree to which contraction time was prolonged (r = 0.88, P < 0.02). To determine whether inotropic effects could be maintained during repeated contractions, muscle strips underwent intermittent 20-Hz train stimulation for a duration of 2 min in presence or absence of gamma-dendrotoxin. Force was significantly greater with than without gamma-dendrotoxin during repetitive stimulation for the first 60 s of repetitive contractions. Despite the approximately 55% higher value for initial force in the presence vs. absence of gamma-dendrotoxin, the rate at which fatigue occurred was not accelerated by the toxin, as assessed by the amount of time over which force declined by 25 and 50%. These data suggest that blocking voltage-activated K+ channels may be a useful therapeutic strategy for augmenting diaphragm force, provided less toxic blockers of these channels can be found.  (+info)

Background. The purpose of this study was to compare the peak electromyography (EMG) of the most commonly-used position in the literature, the prone bent-leg (90°) hip extension against manual resistance applied to the distal thigh (PRONE), to a novel position, the standing glute squeeze (SQUEEZE).Methods. Surface EMG electrodes were placed on the upper and lower gluteus maximus of thirteen recreationally active females (age = 28.9 years; height = 164 cm; body mass = 58.2 kg), before three maximum voluntary isometric contraction (MVIC) trials for each position were obtained in a randomized, counterbalanced fashion.Results. No statistically significant (p | 0.05) differences were observed between PRONE (upper: 91.94%; lower: 94.52%) and SQUEEZE (upper: 92.04%; lower: 85.12%) for both the upper and lower gluteus maximus. Neither the PRONE nor SQUEEZE was more effective between all subjects.Conclusions. In agreement with other studies, no single testing position is ideal for every participant. Therefore,
Looking for Isometric Muscle Contraction? Find out information about Isometric Muscle Contraction. contraction of a muscle expressed in an increase in its tension while its length remains unchanged . In the body, the tension developed by muscles in an... Explanation of Isometric Muscle Contraction
Fatigue in muscles that shorten might have other causes than fatigue during isometric contractions, since both cross-bridge cycling and energy demand are different in the two exercise modes. While isometric contractions are extensively studied, the causes of fatigue in shortening contractions are poorly mapped. Here, we investigate fatigue mechanisms during shortening contractions in slow twitch skeletal muscle in near physiological conditions. Fatigue was induced in rat soleus muscles with maintained blood supply by in situ shortening contractions at 37°C. Muscles were stimulated repeatedly (1 s on/off at 30 Hz) for 15 min against a constant load, allowing the muscle to shorten and perform work. Fatigue and subsequent recovery was examined at 20 s, 100 s and 15 min exercise. The effects of prior exercise were investigated in a second exercise bout. Fatigue developed in three distinct phases. During the first 20 s the regulatory protein Myosin Light Chain-2 (slow isoform, MLC-2s) was rapidly ...
Comments, concepts and statistics about Effect of muscle load tasks with maximal isometric contractions on oxygenation of the trapezius muscle and sympathetic nervous activity in females with chronic neck and shoulder pain..
Willems, Mark E. T. and Northcott, Simon R. (2009) Gender differences after downhill running for voluntary isometric contractions of knee extensor muscles using surface EMG. Medicina Sportiva, 13 (1). pp. 35-42. ISSN 1734-2260 ...
Egaña, M., Crampton, D., Malone, J., McNamara, E. and Warmington, S.A. 2006, Cardiorespiratory responses to near fatiguing sustained and intermittent isometric contractions of the quadriceps muscles,, in Royal Academy of Medicine in Ireland, Biomedical Sciences, Summer Meeting, Springer, London, England. ...
Neurology Research International is a peer-reviewed, Open Access journal that publishes original research articles, review articles, and clinical studies focusing on diseases of the nervous system, as well as normal neurological functioning. The journal will consider basic, translational, and clinical research, including animal models and clinical trials.
Eccentric training may affect the longitudinal adaptation of the muscle. Usually the muscle fiber lengthening during eccentric training is measured by the joint kinematics. Due to tendon compliance, this method offers insufficient information about the muscle fiber behavior. The present study investigated the muscle fiber behavior of the Vastus Lateralis muscle (VL) during eccentric knee contractions in humans by measuring the changes of fascicle length in vivo with ultrasonography, at force levels of 65% and 95% of the maximum voluntary isometric contraction force (MVC). Seven young adults were tested by a Biodex. They performed eccentric knee contractions with one leg at 65% and 95% of their MVC (knee angle 25°-100°, angular velocity 90°/s). Potential joint axis deviations were recorded using a Vicon camera system. Exerted knee moments were captured synchronously with the Vicon system at 1000Hz. Fascicle length of the VL muscle visualized by a 10cm Ultrasound prob. The means and standard ...
In current rehabilitation practice, exercise selection is commonly based on the amount of muscle recruitment demonstrated by electromyographic (EMG) analysis. A preponderance of evidence supports the concept that EMG of a muscle and torque output are positively correlated. This study was designed to investigate the relationship between surface EMG activity of the infraspinatus and torque production during exercises involving shoulder external rotation (ER). A total of 30 participants (average age = 24.6 y) performed maximum voluntary isometric contraction of ER at 5 points within the range of motion of 3 shoulder exercise positions with concomitant surface EMG recording. As a maximal internally rotated position was approached, maximum ER torque and minimum or near-minimum EMG recruitment were demonstrated. Conversely, at maximally externally rotated positions, EMG activity was greatest and torque values were lowest. An inverse relationship between joint torque output and EMG activity was ...
Enhanced muscle weakness is commonly experienced following stroke and may be accompanied by increased susceptibility to fatigue. To examine the contributions of central and peripheral factors to isometric muscle fatigue in stroke survivors, this study investigates changes in motor unit (MU) mean firing rate and action potential duration during, and directly following, a sustained submaximal fatiguing contraction at 30% maximum voluntary contraction (MVC). A series of short contractions of the first dorsal interosseous muscle were performed pre- and postfatigue at 20% MVC, and again following a 10-minute recovery period, by twelve chronic stroke survivors. Individual MU firing times were extracted using surface EMG decomposition and used to obtain the spike-triggered average MU action potential waveforms. During the sustained fatiguing contraction, the mean rate of change of the firing rate across all detected motor units was greater on the affected side (-0.02 ± 0.03 Hz/s) than on the less-affected
Lower Limb Muscle Activation Comparison as Assessed by Maximum Voluntary Isometric Contraction Muscle Strength and Dynamic Muscle Activation Measurements in Total Knee Arthroplasty Subjects Implanted with Medial-pivot or Posterior-stabilized ...
en] In 7 normal subjects we compared the facilitatory effect of isometric contraction of the tibialis anterior on the size of electromyographic responses evoked in this muscle by electric stimuli applied over the cervical column and by electric and magnetic percutaneous stimulation of the motor cortex. No significant difference was found between the degrees of facilitation of the responses to any of the stimuli. Using collision techniques, we also showed that the pyramidal fibers activated by spinal and cortical stimuli are the same. Facilitation induced by isometric contraction (20% maximum) was of similar or greater magnitude than that found with constant vibration of the tendon of the target muscle. In cases where vibration and contraction had equal facilitatory effects, there was no further facilitation of the responses when both conditions were applied together. These findings indicate that the facilitatory effect of isometric contraction of the target muscle essentially originates at a ...
TY - JOUR. T1 - The reliability of the interpolated twitch technique during submaximal and maximal isometric muscle actions. AU - Cooper, Michael A.. AU - Herda, Trent J.. AU - Walter-Herda, Ashley A.. AU - Costa, Pablo B.. AU - Ryan, Eric D.. AU - Cramer, Joel T.. PY - 2013. Y1 - 2013. N2 - The purpose of this study was to examine the test-retest reliability of the percent voluntary activation (%VA) vs. force relationships. Fourteen healthy men (mean 6 SD age = 21 6 2.6 years) and 8 women (age = 21 6 1.8 years) completed 4 maximal voluntary contractions (MVCs) and 9 randomly ordered submaximal isometric plantar flexions from 10 to 100% of the MVC. Transcutaneous electrical stimuli were delivered to the tibial nerve using a highvoltage constant-current stimulator (DS7AH; Digitimer, Herthfordshire, United Kingdom). The %VA was calculated for each maximal and submaximal MVC. Paired-samples t-tests were used to quantify systematic variability, whereas the intraclass correlation coefficients (ICCs), ...
TY - JOUR. T1 - Adenosine triphosphate production rates, metabolic economy calculations, pH, phosphomonoesters, phosphodiesters, and force output during short- duration maximal isometric plantar flexion exercises and repeated maximal isometric plantar flexion exercises. AU - Newcomer, Bradley R.. AU - Boska, Michael D.. PY - 1997/3/18. Y1 - 1997/3/18. N2 - Measurements of adenosine triphosphate (ATP) production rates, metabolic economy, intracellular pH, phosphodiesters, and phosphomonoesters along with the force output were used to study 90-s maximum voluntary contractions and two new exercise protocols (20-10 and 30-16 exercises). The 20-10 exercise consisted of thirty-one 20-s maximal voluntary contractions separated by 10- s rest periods. The 30-16 exercise consisted of twenty 30-s maximal voluntary contractions separated by 16-s rest periods. There were no differences in ATP production rates, metabolic economy, intracellular pH, or force output between the 20-10 and 30-16 exercises. The ...
Thirty-six male subjects from collegiate intramural athletic teams were asked to maintain 50% of their maximum voluntary contraction on an isometric hand dynamometer as long as possible. The subjects were divided into two groups. One group performed individually while the other group, in teams of three men each, competed for a team prize. During the session, the active muscle was continuously monitored by electromyography. The results demonstrated that the introduction of the motivational factors of competition and team presence did not increase the mean endurance time. The EMG analyses indicated that muscle activity was significantly increased when additional motivational factors were introduced. It was concluded that team presence and competition are better described as stress factors which increase the general arousal level of the subject and reduce the efficiency of the muscles. (Author)(*MUSCLES
Dichotomous Effects of Isometric Secondary Amines Containing an Aromatic Nitrile and a Nitro Group on Human Aortic Smooth Muscle Cells: Syntheses, Nitrosation and Cell Culture Studies ...
Dichotomous Effects of Isometric Secondary Amines Containing an Aromatic Nitrile and a Nitro Group on Human Aortic Smooth Muscle Cells: Syntheses, Nitrosation and Cell Culture Studies ...
The acute cardiovascular responses to isometric exercise 6 Acute local circulation response to isometric exercise 7 Mechanisms that control the acute response to isometric exercise 7 a The role of central command during isometric exercise 7 b The role of the exercise pressor reflex during isometric exercise 8.
Purpose: This study examined whether a higher protein diet following strenuous exercise can alter markers of muscle damage and inflammation in older adults. Methods: Using a double-blind, independent group design, 10 males and eight females (age 57 ± 4 years; mass 72.3 ± 5.6 kg; height 1.7 ± 6.5 m) were supplied with a higher protein (2.50 g·kg−1·day−1) or moderate protein (1.25 g·kg−1·day−1) diet for 48 hr after 140 squats with 25% of their body mass. Maximal isometric voluntary contractions, muscle soreness, creatine kinase, Brief Assessment of Mood Adapted, and inflammatory markers were measured preexercise, and 24 hr and 48 hr postexercise. Results: The maximal isometric voluntary contractions decreased postexercise (p = .001 ...
The pathogenesis of widespread pain and fibromyalgia (FM) is unknown. Altered responses from the hypothalamus-pituitary-adrenal axis, sympathetic nervous system and muscular system have been suggested as being of importance. The present study was undertaken to determine: (i) whether the sympathoadrenal response to repetitive isometric contractions until exhaustion is altered in patients with FM, and (ii) whether sympathoadrenal responses are associated with muscle fatigue and pain during exercise. Nineteen women with FM, and 19 healthy women matched for age, smoking and self-reported physical activity, participated. Maximal voluntary contraction (MVC), repetitive isometric contractions (6s contraction and 4s resting phases) were performed with both quadriceps muscles at 30% of MVC until exhaustion. Muscle activity was recorded from the quadriceps muscles by surface electromyography (EMG). Plasma adrenalin (Adr), noradrenalin (NAdr) and cortisol were measured and perceived exertion and pain ...
This study investigated if men and women, matched for initial strength (41 pairs), differed in their response to a single set (50 repetitions) of high force eccentric exercise of the elbow flexors on a curl bench. Maximal isometric force at 90 degrees, and muscle soreness before, immediately after, and 34 hours after exercise were measured. Changes in strength were assumed an indicator of muscle damage.. Women exhibited consistently greater force losses and fatigue than men. After 34 hours, women still displayed a greater indication of muscle damage than men. No gender differences were observed in soreness variables.. Implication. Women fatigue more and lose strength to a greater degree than do men when matched for the same level of initial strength.. Return to Table of Contents for this issue.. ...
Kiefer, A. W., Ford, K. R., Paterno, Mark V., Schmitt, L. C., Myer, G. D., Riley, M. A., Shockley, K., & Hewett, T. E. (in press). Inter-segmental postural coordination measures differentiate athletes with ACL reconstruction from uninjured athletes. Gait & Posture.. Athreya, D., Van Orden, G. C., & Riley, M. A. (2012). Feedback about isometric force production yields more random variations. Neuroscience Letters, 513, 37-41 ...
If youve ever seen a mime trying to escape his invisible box, youve seen a playful example of an isometric contraction. Isometric exercises are strength-training exercises that involve the ...
Experimental setup. Experimental apparatus used to evaluate ankle voluntary dorsi-flexion movement and isometric maximal voluntary contractions.
Isometric exercises -- the plank, for example -- strengthen your muscles without moving your body. As with any other form of strength-training exercise, however, isometric strength training doesnt ...
This article was originally published in: European Journal of Applied Physiology (2006) 96/3, 235-240. The original publication is available at here. ...
The modulation of motor evoked potentials (MEPs), an index of corticospinal excitability, has been shown to increase during isometric contractions with incremental torque output in accordance with the contribution between ...
Posture is area that should be regularly assessed through physical examinations of young athletes by a physician trained in the assessment of posture
Quantifying standing steadiness may be a useful method of detecting neurotoxicity in epidemiological studies. Unfortunately, use of quantitative standing steadiness outcomes in epidemiologic studies has been limited by lack of standardization of methods, insufficient availability of normative data, and inadequately characterized effects of...
The rotating plank is an absolute game changer for those looking to up their core strength. As discussed in our previous core training article, the most efficient way of training the muscles responsible for trunk strength and stability is through isometric contractions involved in spinal stabilization movements.. This exercise does just that, packing both anti-extension and anti-rotation benefits. You should feel your entire midsection light up when performing these, especially your obliques, which play a huge role in preventing and aiding in trunk lateral flexion and rotation.. ...
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies. ...
Rave 3 Syrup is used for vitamin deficiency, stop tumours growth, inflammation and other conditions. Rave 3 Syrup contains the following active ingredients: Antioxidant, and Multivitamin.
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Teaching proper loading techniques ensures that athletes can move optimally, engage the right muscles for efficient power, and reduce the risk of injury.
This workout took place on the last day of December, but Im pasting it into my 2012 log. For those of you trying to figure out what Mesocycle, etc means, I try to organize my training to better arrange my videos, etc. 4 Weeks make 1 Mesocycle. This is the start of Mesocycle 41 ...
A lot of times, your deadlift stalls out because you lack isometric strength in your lats. Lets fix that... and build some new mass too.
1) Implements the ISM of Hassan et al 2) Tests it with the MD framework ProtoMol 3) Compare average force error over trajectory
Prolong by removing wet sheet when sweating and Dry Pack with Hot Water Bottle, rubbing of trunk and limbs over blankets and isometric exercises ...
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TY - JOUR. T1 - Two maximal isometric contractions attenuate the magnitude of eccentric exercise-induced muscle damage. AU - Chen, Hsin Lian. AU - Nosaka, Kazunori. AU - Pearce, Alan J.. AU - Chen, Trevor C.. PY - 2012/8/1. Y1 - 2012/8/1. N2 - This study investigated whether maximal voluntary isometric contractions (MVC-ISO) would attenuate the magnitude of eccentric exercise-induced muscle damage. Young untrained men were placed into one of the two experimental groups or one control group (n = 13 per group). Subjects in the experimental groups performed either two or 10 MVC-ISO of the elbow flexors at a long muscle length (20° flexion) 2 days prior to 30 maximal isokinetic eccentric contractions of the elbow flexors. Subjects in the control group performed the eccentric contractions without MVC-ISO. No significant changes in maximal voluntary concentric contraction peak torque, peak torque angle, range of motion, upper arm circumference, plasma creatine kinase (CK) activity and myoglobin ...
Purpose : The purpose of this study was to assess the effect of bridging stabilization exercises of trunk muscles activity on a Swiss ball according to change of position. Methods:30 healthy university students volunteered to participate in this study. Subjects were required to complete following three exercise positions. Exercise position 1; Supine bridge with Swiss ball, Exercise position 2; Side bridge with Swiss ball, Exercise position 3; Prone bridge with Swiss ball. Surface electromyography from selected trunk muscles was normalized to maximum voluntary isometric contraction. Results : A repeated measures of ANOVA with Duncan`s correction was used to determine the influence of exercise type on muscle activity for rectus abdominis, external oblique, erector spinae. The erector spinae of exercise position 1 showed significantly higher muscle activity than exercise position 2, 3(p
Author: Kenville, Rouven et al.; Genre: Journal Article; Published online: 2020-04-14; Keywords: Motor system; Muscle strength; Transcranial direct current stimulation (tDCS); Whole-body movement. ; Title: Cerebellar transcranial direct current stimulation improves maximum isometric force production during isometric Barbell squats
Looking for online definition of isometric contraction in the Medical Dictionary? isometric contraction explanation free. What is isometric contraction? Meaning of isometric contraction medical term. What does isometric contraction mean?
Twenty women with primary fibromyalgia syndrome and 20 age matched healthy women were investigated. The subjects performed maximum voluntary isokinetic contractions of the right quadriceps in an isokinetic dynamometer. Maximum voluntary isometric contractions of the right quadriceps were performed w …
Looking for online definition of length-tension relationship in the Medical Dictionary? length-tension relationship explanation free. What is length-tension relationship? Meaning of length-tension relationship medical term. What does length-tension relationship mean?
It has been thought that intramuscular ADP and phosphocreatine (PCr) concentrations are important regulators of mitochondorial respiration. There is a threshold work rate or metabolic rate for cellular acidosis, and the decrease in muscle PCr is accelerated with drop in pH during incremental exercise. We tested the hypothesis that increase in muscle oxygen consumption ( o2mus) is accelerated with rapid decrease in PCr (concomitant increase in ADP) in muscles with drop in pH occurs during incremental plantar flexion exercise. Five male subjects performed a repetitive intermittent isometric plantar flexion exercise (6-s contraction/4-s relaxation). Exercise intensity was raised every 1 min by 10% maximal voluntary contraction (MVC), starting at 10% MVC until exhaustion. The measurement site was at the medial head of the gastrocnemius muscle. Changes in muscle PCr, inorganic phosphate (Pi), ADP, and pH were measured by 31P
Background Currently available local anesthetics approved for single-injection peripheral nerve blocks have a maximum duration less than 24 hours. bupivacaine (0-80 mg) was mixed with normal saline to produce 30 mL of study fluid. Each subject received two different doses one on each part applied randomly inside a double-masked fashion. The end points included the maximum voluntary isometric contraction (MVIC) of the DMXAA (ASA404) quadriceps femoris muscle mass and tolerance to cutaneous electrical current in the femoral nerve distribution. Measurements were performed from baseline until quadriceps MVIC returned to 80% of baseline bilaterally. Results There were statistically significant dose reactions in MVIC (0.09% / mg SE = 0.03 95 CI 0.04 to 0.14 p = 0.002) and tolerance to cutaneous current (?0.03 mA / mg SE = 0.01 95 CI ?0.04 to 0.02 p < 0.001) however in the opposite direction than expected (the higher the dose the lower the observed effect). This inverse relationship is definitely ...
Background: The aim of the study was to estimate differences in bioelectrical activity between rectus femoris (RF) and vastus medialis (VM) muscles of each lower limb. Material/Methods: 29 female and 18 male adult subjects participated in the study. Each subject performed the following quadriceps contractions with each lower limb: concentric, isometric, eccentric and 30-sec. long maximal voluntary isometric contraction. 3 parameters were obtained in surface electromyography (SEMG): mean RMS amplitude (RMS), mean percentage value of maximal voluntary contraction (%MVC) and mean frequency (MF). Results: RF occurred to have a lower percentage activity (-28.43%) and absolute amplitude (- 36.57%) value than VM during all three basic forms of contraction against gravity. Except the RMS values for concentric contraction, all the mentioned parameters were significantly different. In contrast, RF had a higher MF rate than VM. Differences were at the mean level of 22.57% for all activities. Conclusions: ...
Hip torque production is associated with certain knee injuries. The hip rotators change function depending on hip angle. Objective: To compare hip-rotator torque production between 3 angles of hip flexion, limbs, and sexes. Design: Descriptive. Setting: University sports medicine research laboratory. Participants: 15 men and 15 women, 19-39 y. Intervention: Three 6-s maximal isometric contractions of the hip external and internal rotators at 10°, 40°, and 90° of hip flexion on both legs. Main Outcome Measure: Average torque normalized to body mass. Results: Internal-rotation torque was greatest at 90° of hip flexion, followed by 40° of hip flexion and finally 10° of hip flexion. External-rotation torque was not different based on hip flexion. The nondominant legs external rotators were stronger than the dominant legs, but the reverse was true for internal rotators. Finally, the men had more overall rotator torque. Conclusions: Hip-rotation torque production varies between flexion angle, ...
Definition of concentric contraction in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is concentric contraction? Meaning of concentric contraction as a finance term. What does concentric contraction mean in finance?
This thesis investigated sport specific responses of diastolic mechanics at rest and during submaximal exercise. Two-dimensional speckle tracking echocardiography (STE) was used to assess diastolic mechanics at rest and whilst triathletes (TRI, n=9, 32 ± 7 years), long distance runners (LDR, n=7, 34 ± 3 years), resistance trained (RT, n=5, 24 ± 5 years) and untrained controls (CON, n=5, 29 ± 5 years) performed dynamic and static exercise. Cycling consisted of 5 minute stages at 30% and 60% maximum workload (Wmax), and leg extension involved 15 second contractions at 40% and 75% maximal voluntary isometric contraction (MVIC). Peak untwisting velocity (PUV), apical and basal rotation velocities did not differ between groups at rest or during exercise (p,0.05). PUV increased in TRI from rest to 30% and 60% Wmax (p,0.01), remained unchanged in LDR, RT and CON from rest to 30% (p,0.05, p,0.05, p,0.05, respectively) and 60% Wmax (p=0.018, p,0.05, p,0.05, respectively). PUV did not change from rest ...
Mutungi, GM and Ranatunga, KW (2000) Sarcomere length changes during end-held (isometric) contractions in intact mammalian (rat) fast and slow muscle fibres. Journal of Muscle Research and Cell Motility, 21 (6). pp. 565-575. Full text not available from this repository ...
Beck M, Giess R, Wuerffel W, Magnus T, Ochs, G, Toyka KV. Comparison of Maximal Voluntary Isometric Contraction and Drachmans Hand-Held Dynamometry in Evaluating Patients with Amyotrophic Lateral Sclosis. Muscle Nerve. 1999; 22: 1265-1270. Bohannon RW. Hand-Held Dynamometry; Stability of Muscle Strength Over Multiple Measurements. Clinical Biomechanics. 1986: 2:74-77. Wang CY, Olson SL, Protas EJ. Test-Retest Strength Reliability: Hand-Held Dynamometry in Community-Dwelling Elderly Faller. Arch Phys Med Rehabil. 2002; 83: 811-5. Shefner J, Cudkowicz ME, Maragakis N, Cedarbaum JM, Lee J, Jones D, Watson ML, Shaver K, Chen M, Saikali K, Mao J, Russell AK, Hansen L, Malik F, Wolff AA, for the NEALS/Cytokinetics Study Team. Safety, tolerability and pharmacodynamics of a skeletal muscle activator in Amyotrophic Lateral Sclerosis. (submitted for publication) ...
1. Muscle fibres may be subdivided into type I (with slow-twitch contractile properties) and type II (fast-twitch) depending on their myosin adenosine triphosphatase activity. In voluntary isometric contractions type I fibres are utilized at low forces (,20% of maximum) whereas type II fibres are recruited in addition at high forces. This physiological recruitment order has enabled us to measure the relaxation rate of type I and II fibres in vivo in normal human subjects.. 2. Relaxation rate was measured in 16 subjects from low (10% of maximum) and maximum isometric quadriceps contractions and the muscle-fibre type composition determined from needle-biopsy specimens in 10 subjects. The relaxation rate of type II fibres was calculated to be twice as fast as that of type I.. 3. It was not possible to estimate, from studies in 33 quadriceps muscles (25 normal subjects), the contribution of type II fibres to overall fibre area from the relaxation rate as determined from electrically stimulated ...
Definition of eccentric contraction in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is eccentric contraction? Meaning of eccentric contraction as a finance term. What does eccentric contraction mean in finance?
Isotonic Vs. Isometric Contraction. Every exercise you do involves some sort of muscle contraction. Exercises with movement involve isotonic muscle contractions and exercises without movement involve isometric muscular contractions. Knowing the difference between these two different types of contractions can help you ...
|br/|Signals Analyzed:|br/| • Isometric Muscle Contraction|br/| • Isotonic Muscle Contraction |br/||br/| The basic version of HSE-ACAD for smooth muscles calculates the following parameter: |br/||br/| • Resting tension |br/||br/| The HSE-HA ACAD software can be adapted to virtually any experimental investigation in tissue bath experiments. It is possible to acquire signals from isotonic (displacement) or isometric (force) measurements. The isotonic displacement measurement is used on smooth muscles, for example on ileum, ductus deferens, lung strips, also bladder... Isometric force measurement is used with tracheal muscle, atrium, papillary muscle, aortic rings, veins or other vessel rings. Experiments on spontaneously beating or electrically stimulated tissues are also possible. Various parameters can be derived from these signals depending on the model used. During data acquisition all acquired signals and derived parameters are stored on the hard disc and can be displayed graphically
Leg-muscle force during maximal voluntary isometric contractions was measured 2 d after exercise (Day 3), and the BCAA supplementation suppressed the muscle-force decrease (to ~80% of the value recorded under the control conditions) observed in the placebo trial. Plasma BCAA concentrations, which decreased after exercise in the placebo trial, were markedly elevated during the 2 hr postexercise in the BCAA trial. Serum myoglobin concentration was increased by exercise in the placebo but not in the BCAA trial. The concentration of plasma elastase as an index of neutrophil activation appeared to increase after the squat exercise in both trials, but the change in the elastase level was significant only in the placebo trial ...
During a stretch- shortening cycle (SSC), muscle force attained during concentric contractions (shortening phase) is potentiated by the preceding eccentric contractions (lengthening phase). The purpose of this study was to examine the influence of joint angular velocity on force potentiation induced by SSC (SSC effect). Twelve healthy men (age, 24.2 ± 3.2 years; height, 1.73 ± 0.05 m; body mass, 68.1 ± 11.0 kg) participated in this study. Ankle joint angle was passively moved by a dynamometer, with range of motion from dorsiflexion (DF) 15° to plantarflexion (PF) 15°. Muscle contractions were evoked by tetanic electrical stimulation. Joint angular velocity of concentric contraction was set at 30°/s and 150°/s. Magnitude of SSC effect was calculated as the ratio of joint torque obtained by concentric contraction with preliminary eccentric contraction trial relative to that obtained by concentric contraction without preliminary eccentric contraction trial. As a result, magnitude of SSC effect
In the Functional Range Conditioning system PAILs and RAILs are our primary means of expanding a joints range of motion, whereas our Controlled Articular Rotations (CARs) are used for maintenance and assessment.. PAILs stand for Progressive Angular Isometric Loading. This refers to an isometric contraction at an end range position for the tissues being placed on stretch.. RAILs stand for Regressive Angular Isometric Loading. This refers to isometric contractions at end range position for the tissues on the closing side of the joint, or the muscles on the opposite side of what is being stretched.. It is well documented in the literature that poor hip mobility can lead to altered lumbar motion. For example, if somebody lacked hip extension they would be more likely to extend their spines to make up for the lack of motion. This is why we should be making sure we keep our hips as mobile as possible.. Check out the video below and see how the 90/90 can improve your hip mobility and low back ...
This paper presents findings from a study of five healthy subjects performing 50% maximum voluntary contraction until complete fatigue of the muscle. An overlapping window technique was used to find the values for mean frequency (MNF), median frequency (MDF) of the power spectrum, root mean square (RMS) and muscle fibre conduction velocity (MFCV). The surface electromyography signal (sEMG) was collected from the vastus lateralis muscle using a three channel Laplacian electrode. The results show the MNF and MDF values showed a consistent trend with each other where they remained at steady values between 20-30% and 75-80% of the signal after which they fell 15-30% of this value. The RMS showed a linear increase in value. The MFCV showed a similar trend to that found in the MNF and MDF values ...
Before I start talking about using different contraction types in training and the benefits they will have, first I must explain to anyone who doesnt know about the 3 different types of contraction. Keeping it nice and basic, there are 3 different ways that your muscle can contract in order to move a part of your body. Concentric - a concentric contraction is where the muscle shortens in length causing your bodypart to move. For example when you concentrically contract your bicep, it shortens and your arm bends (flexes). Most people who will train will be primarily focused on this type of contraction as it is the one that moves the weight against the resistance. For example it is the concentric contraction that pushes the bar off your chest to lockout on a bench press. Eccentric - an eccentric contraction is the lengthening of the muscle. This occurs when you lower the weight under control. Its the opposite movement to the concentric contraction but it isnt the antagonistic muscle that
An understanding of the changes in force variability in both the time and frequency domains could help explain the decreased steadiness and the fall risk in subjects who are associated with fatigue (Schwendner et al. 1997). Since the relationship between fatigue and unsteadiness in both the time and frequency domains of the lower extremity remains uninvestigated, this study aimed to determine whether a reduction in steadiness of the force signal is associated with a shift towards higher frequency components. As a first step, the reliability and repeatability of a torque control test set-up was established by assessing young, healthy subjects and was used to test the change in levels of force fluctuation after fatiguing exercises. The results indicated that time-domain measures of accuracy and steadiness of continuous torque production had excellent reliabilities (Shrout & Fleiss 1979; Bruton et al. 2000), whereas frequency-domain measures had relatively lower values of reliability. Furthermore, ...
The foundations for this topic can be found in the previous 4 articles in the series. Building off the understanding of viscoelastic tissues that are sensitive to the rate at which force is applied, we will examine training strategies designed to maximize muscle stimulation while avoiding injury. There are 3 types of muscle contraction:. Concentric - the muscle is shortening while contracting (the positive rep). Isometric - the muscle does not change length while contracting. Eccentric - the muscle is lengthening while contracting (the negative rep). It is widely misstated, and then repeated by others, that eccentric contractions produce more force than isometric contractions which produce more force than concentric contractions. This is not true. The force generated by muscle contraction is determined by the equation for torque reviewed in the last article, independent of the shortening or lengthening during contraction (minus a subtle detail - hysteresis - which is beyond the scope of our ...
The aim of the present study was to investigate the EMG-joint angle relationship during voluntary contraction with maximum effort and the differences in activity among three hamstring muscles during knee flexion. Ten healthy subjects performed maximum voluntary isometric and isokinetic knee flexion. …
This study analyzed the effect of blood-flow restriction on running economy untrained young men (N = 18). Ss were randomly divided into two groups: i) blood-flow restriction, and ii) walking training without blood-flow restriction. Both groups underwent the same testing pre- and post-training: i) treadmill incremental test to obtain the maximal oxygen uptake (VO2max); ii) rectangular treadmill test at 8 km/h to measure running economy; iii) two maximum isometric contractions of the knee extensors and knee flexors to measure maximum voluntary contraction, maximum rate of force development, and semitendinosus, biceps femorus, rectus femorus, and vastus lateralis EMG activity; iv) estimation of plantar flexors muscle-tendon stiffness; and v) measurement of the thigh muscle-bone cross sectional area using ultrasound imaging. Twenty-eight training sessions (7 days per week) of 20-minutes of continuous walking were performed. The blood-flow restriction group trained with both legs restricted at a ...
A skeletal muscle that is stretched while contracting will produce more force at steady state than if it is stretched passively and then stimulated to contract. This phenomenon is known as residual fo
1. Plasma catecholamine, haemodynamic and metabolic responses to sustained isometric exercise were studied in eight healthy subjects, who maintained handgrip at the 30% level of maximal voluntary contraction (MVC) for as long as possible.. 2. The sustained handgrip was accompanied by a significant increase in plasma noradrenaline (NA) and adrenaline (A) concentrations.. 3. The increase in plasma NA during handgrip was greater than that associated with heavy dynamic work involving large muscle groups.. 4. The results suggest that the known haemodynamic responses to static effort are related to a powerful activation of the adrenergic system, which may result from a reflex mechanism initiated in the exercising muscles. ...
Properties of the human neck which may influence a persons susceptibility to whiplash injury during lateral impact have been studied in 96 normal subjects. Subjects were chosen on the basis of age, sex, and stature and data were grouped into six primary categories based on sex (F, M) and age (18-24, 35-44, 62-74). The data include: measures of head, neck and body anthropometry in standing and simulated automotive seating positions, three-dimensional range of motion of the head and neck, head/neck response to low-level acceleration, and both stretch reflex time and voluntary isometric muscle force in the lateral direction. Reflex times are found to vary from about 30 to 70 ms with young and middle aged persons having faster times than older persons, and females having faster times than males. Muscle strength decreases with age and males are, on the average, stronger than females ...
In this section you will learn about isometric strength and find some exercises. Isometric or static strength training is an exercise form where no motion is involved. The muscle is contracted statically, but there is no movement at the joint.
Isometric exercise is a modified type of resistance training often used for rehabilitating an injury. Its also a useful fitness tool for people with arthritis, since it puts less stress on the joints. Isometric exercises arent an effective strategy for increasing athletic performance but they can help strengthen an ...
A versatile bidirectional isometric exercise device is provided in the form of an inflatable flexible exercise ball (10A-C), about 46 cm (18 inches) in diameter, fitted with a pair of looped handles (12A-B, 30A, 30C), secured to diametrically opposite points of the ball, through which arms or legs can be placed for performing specialized exercises that use the ball (10A-C) in a tension mode. The ball (10A-C) is only partially inflated so as to provide soft compliant accommodation to various body surfaces, and can be utilized bidirectionally, i.e. either in compression or in tension, in conjunction with various body parts such as hands, legs, knees, feet, etc., for a broad array of isometric muscle exercises directed to overall body strengthening, particularly for persons prone to and/or desiring protection from the effects of osteoporosis. A sequence of recommended exercises may be depicted directly on the surface of the ball (10A-C). Attachment of the handles (12A-B) to the main ball portion may be
TY - JOUR. T1 - Muscle activation is enhanced with multi- and uni-articular bilateral versus unilateral contractions. AU - Behm, D.G.. AU - Power, K.E.. AU - Drinkwater, Eric. N1 - Imported on 12 Apr 2017 - DigiTool details were: Journal title (773t) = Applied Physiology, Nutrition and Metabolism. ISSNs: 1066-7814; PY - 2003. Y1 - 2003. N2 - Ten resistance trained (RT) and 6 non-resistance trained (NRT) subjects were used to determine differences in quadriceps activation between isometric single and double knee extensions and squat contractions. Greater inactivation, as measured by the interpolated twitch technique, was recorded with single (RT: 16.5%, NRT: 17.6%) than double leg extensions (RT: 8.4%, NRT: 13.4%) or squats (RT: 4.03%, NRT: 1.7%). There was no significant difference between the maximum voluntary contraction (MVC) force of the dominant leg during single and double leg extensions. However, in NRT subjects, the contralateral or non-dominant leg during double leg extensions exhibited ...
Strong interactions between cross-bridges (XB) and regulatory units (RU) lead to a steep response of cardiac muscle to an increase in intracellular calcium. We developed a model to quantitatively assess the influence of different types of interactions within the sarcomere on the properties of cardiac muscle. In the model, the ensembles consisting of cross-bridge groups connected by elastic tropomyosin are introduced, and their dynamics is described by a set of partial differential equations. Through large scans in the free energy landscape, we demonstrate the different influence of RU-RU, XB-XB, and XB-RU interactions on the cooperativity coefficient of calcium binding, developed maximal force, and calcium sensitivity. The model solution was fitted to reproduce experimental data on force development during isometric contraction, shortening in physiological contraction, and ATP consumption by acto-myosin. On the basis of the fits, we quantified the free energy change introduced through RU-RU and ...
Principal Investigator:YAMAZAKI Yoshihiko, Project Period (FY):1992 - 1993, Research Category:Grant-in-Aid for General Scientific Research (C), Research Field:体育学
Isometric exercises, or static exercises, are quick, intense, and may help boost your endurance on the bike. Heres what you should know.
This is a three-stage exercise. Sit comfortably in an upright position. Your head is erect. First, place your right hand, fingers pointing upward, on the right side of your face, directly in front of your ear. Using your right hand to provide gentle continuous resistance, try to turn your head to the right. Imagine youre trying to look over your right shoulder. Make sure to keep your hand in its initial position - dont let it slip!. Youll feel your neck muscles contracting on the right. This is an isometric exercise, so youre not really going anywhere. Apply continuous muscular contraction and continuous gentle resistance for 6 seconds. Gently relax and return to the starting position.. Next, begin by turning your head to the right, to about halfway of your pain-free range of motion. Place your right hand, fingers pointing upward, on the right side of your face, directly in front of your ear. Apply gentle continuous resistance as you try to turn your head to the right. Apply continuous ...
System, method and apparatus for carrying out isometric exercises for therapeutic purposes. As employed in a therapeutic mode the apparatus may only be programmed within mandated therapeutic parameter limitations. During therapeutic trials, the user is visually and aurally cued throughout the test sequence and the therapeutic data evolved during the regimen is recorded and recoverable from archival memory. Particular target force modes can be selected to allow stimulation of nitric oxide release, and modulation of serum lipid composition.
You want to keep those great thighs of youth, but your busy schedule makes it difficult to exercise. Isometric exercises, contractions performed from a static position without joint movement, help ...
I do not know what natural contractions feel like however contractions brought on by pitocin are the precise absolute plain satan. At 38 weeks I woke to them happening every 10 minutes - tho they eased after I moved & they had been brief & not painful, so I didnt fear an excessive amount of.. Apply labor contractions are in any other case known as Braxton Hicks contractions and are widespread from week 32 until birth. Nonetheless, in the event youre writing a tutorial paper or the rest thats formal, you could want to keep away from contractions. The time between contractions includes the length or length of the contraction and the minutes in between the contractions (called the interval).. Should you go to the hospital only to search out out that youre having false labor, dont feel unhealthy about it. It is sometimes laborious to know the difference between actual and false labor. One of the reasons it is troublesome to answer the question what do contractions feel like is because the ...
In this article, we describe an approach to model the electromechanical behavior of the skeletal muscle based on the Huxley formulation. We propose a model
My work involves Tomography of Insect flight muscle, which provides 3-D in situ information of various components of the muscle. 3-D Correspondence analysis is used to process a large number of repeats extracted from tomograms. By atomic model fitting, we can access details of the interaction between muscle proteins. Tomograms of muscles in different states have been collected, including the Ca-activated isometric contraction, and its response to quick stretch and quick release. With the help of newly-developed techniques and improved facilities, we hope to get a better understanding of muscle activation, force-generation, responses to length-changing, and various other mechanisms.. ...
I would be very careful with asymmetric movements, especially with heavy weight. Ive incorporated these types of movements in my workout over the years and have found some problems. The heavy lunge for example created bad strains in my sacro-iliac joint, whereas two-leg exercises are no problem. Kickbacks, DB rows, etc. started giving me severe strains in the obliques and even illipsoas muscles. All problems went away when I removed these asymmetric movements. Asymmetric movements with weights seem natural, after all walking and running are asymmetric, but when done with very heavy weight it can simply create too much torque for some of the small stabilizing muscles that have to maintain a strong isometric contraction for the duration of a set. I also notice that with heavy asymmetric exercises, theres a tendency to cheat more, borrowing from the stabilizing muscles at the expense of the primary movers.. ReplyDelete ...
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Answer: The #majorkey is understanding what type of contractile action is needed to both generate and absorb force.. Force absorption = eccentric. Force production = concentric. Absorbing force requires accepting the forces imparted on a body, and an eccentric contraction is needed for that acceptance. Whereas producing force requires going against the forces imparted on the body, thus a concentric contraction.. Assuming no secondary compensations, there are certain infrasternal angles (ISA) that have greater eccentric ventral cavity bias, and some that have a concentric bias:. Narrow ISA = eccentric bias = Force acceptor. Wide ISA = Concentric bias = Force producer. Now there is a HUGE (HYOOGE? SP) caveat to this: Assuming no secondary compensations.. This is a poor assumption because it seems like all the fam nowadays have compensations left and right. You can have narrows that develop concentric biases that make force absorption whack, and you can have wides that develop weird eccentric ...
"Cortical control of human motoneuron firing during isometric contraction". Journal of Neurophysiology. 77 (6): 3401-5. doi: ... A tremor is an involuntary, somewhat rhythmic, muscle contraction and relaxation involving to-and-fro movements of one or more ... Although all of the heart's cells have the ability to generate action potentials that trigger cardiac contraction, the ...
Salenius, S. (1997). "Cortical control of human motoneuron firing during isometric contraction". Journal of Neurophysiology. 77 ... electroencephalography to study functional coupling between cortical activity and electromyograms during voluntary contractions ...
... then the contraction is a tetanus. Length-tension relationship relates the strength of an isometric contraction to the length ... An isometric contraction of a muscle generates tension without changing length. An example can be found when the muscles of the ... A muscle contraction is described as isometric if the muscle tension changes but the muscle length remains the same. In ... In eccentric contraction, the tension generated while isometric is insufficient to overcome the external load on the muscle and ...
The Involuntary Contraction Follow Isometric Contraction of Skeletal Muscle in Man, A. Forbes, P.C. Baird, and A. McH. Hopkins ... 1926-09-01). "The involuntary contraction following isometric contraction of skeletal muscle in man". American Journal of ... 1, 81-103, September, 1926 The Relative Duration of Contraction in Flexors And Extensors, P.C. Baird, Jr., and J.F. Fulton. The ...
... though contraction strength may be varied. This is in contrast to isotonic contractions, in which the contraction strength does ... On this basis, an overcoming isometric may additionally be referred to as being an isometric press or an isometric pull. In ... An isometric exercise is a form of exercise involving the static contraction of a muscle without any visible movement in the ... Examples of preparatory isometric presses in sport The jumper on the left performs a distinctive isometric press, primarily by ...
The patient performs an isometric flexion contraction against resistance of the therapist (Speed's Test). When the therapist's ...
Gwin JT, Ferris DP (June 2012). "An EEG-based study of discrete isometric and isotonic human lower limb muscle contractions". ... Electrocortical dynamics were studied in relation to isotonic and isometric lower limb muscle contractions. EEG in combination ...
6-bisphosphate in human skeletal muscle during isometric contraction". Biochem. J. 258 (3): 915-8. doi:10.1042/bj2580915. PMC ... 6. It increases in concentration during skeletal muscle contraction. 7. Its dephosphorylation yields glucose-6-phosphate, which ... 6-bisphosphate content in rat skeletal muscle during contraction". Biochem. J. 240 (3): 747-51. doi:10.1042/bj2400747. PMC ...
Physiological Contraction speed in Isometric contractions Rate of rise of force Time to peak of a twitch contraction (response ... This is tested by determining the recruitment threshold of a motor unit during isometric contraction in which the force is ... "The orderly recruitment of human motor units during voluntary isometric contractions". J. Physiol. 230 (2): 359-70. doi:10.1113 ... "Some Properties of Motor Unit Action Potential Trains Recorded during Constant Force Isometric Contractions in Man". Kybernetik ...
Thus the tension is reduced.[citation needed] Isometric exercise (contraction, no movement) Stretching (passive, no contraction ... A near isotonic contraction is known as Auxotonic contraction. There are two types of isotonic contractions: (1) concentric and ... Isotonic contractions differ from isokinetic contractions in that in isokinetic contractions the muscle speed remains constant ... an isotonic contraction will keep force constant while velocity changes, but an isokinetic contraction will keep velocity ...
The frequency content of common synaptic inputs to motoneurones studied during voluntary isometric contraction in man. The ...
"Influence of structure on the tissue dynamics of the human soleus muscle observed in MRI studies during isometric contractions ... "Differential displacement of the human soleus and medial gastrocnemius aponeuroses during isometric plantar flexor contractions ...
Flexibility may be increased when isometrics are performed at joint range of motion extremes. These isometric contractions ... Public domain pamphlets on isometric exercises Isometric exercises tutorial Alexander Zass Example of an isometric exercise ... Isometric exercise tools perform exercises or strength test using static contraction of a muscle without any visible movement ... Isometric exercises have some differences in training effect as compared to dynamic exercises. While isometric training ...
Oct 2008). "Recovery from supraspinal fatigue is slowed in old adults after fatiguing maximal isometric contractions". J Appl ... Isometric strength and physical cross-sectional area of the elbow flexors and elbow extensors are reduced in old compared with ... Compared to the young group, the old group has lower dorsiflexors isometric torque at all angles, has lower knee extensors ... However, for the maximal effort contractions, there is an appreciable difference in discharge rates between the two age groups ...
Isometric contractions are skeletal muscle contractions that do not cause movement of the muscle. However, isotonic ... There are four main types of muscle contraction: twitch, treppe, tetanus and isometric/isotonic. Twitch contraction is the ... The contraction of all the sarcomeres results in the contraction of the whole muscle fiber. This contraction of the myocyte is ... In twitch contraction the length of the contraction may vary depending on the size of the muscle cell. During treppe (or ...
"Intra-ocular pressure changes during maximal isometric contraction: does this reflect intra-cranial pressure or retinal venous ... Movaffaghy, A.; Chamot, S.R.; Petrig, B.L.; Riva, C.E. (1998). "Blood Flow in the Human Optic Nerve Head during Isometric ... Marcus, DF; Edelhauser, HF; Maksud, MG; Wiley, RL (September 1974). "Effects of a sustained muscular contraction on human ... "The Comparison of Intraocular Pressure Reductions after Isometric and Isokinetic Exercises in Normal Individuals". ...
... concentric contraction). It also functions to 'lock' the ankle, as in toe-kicking a ball, when held in an isometric contraction ... It functions to stabilize the ankle as the foot hits the ground during the contact phase of walking (eccentric contraction) and ...
Maganaris, Constantinos N.; Baltzopoulos, Vasilios (2000). "In Vivo Mechanics of Maximum Isometric Muscle Contraction in Man: ... It was originally thought that the distance between aponeuroses did not change during the contraction of a pennate muscle, thus ...
Maganaris C.N., Baltzopoulos V. (2000). In vivo mechanics of maximum isometric muscle contraction in man: Implications for ... It is typically used to describe the contraction properties of pennate muscles. It is not the same as the anatomical cross- ...
Moreover, usage of the work loop technique as opposed to other modes of contraction, such as isometric, isotonic and ... For example, a muscle that generates force without changing length (isometric contraction) will show a vertical line 'work loop ... To elicit muscle contraction, the muscle is stimulated by a series of electrical pulses delivered by an electrode to stimulate ... In 1960, the work loop method was introduced to explore muscle contractions of both variable speed and variable force. These ...
Contraction of muscle under isometric conditions results in a muscle belly displacement. A tensiomyography sensor is connected ... Delay time (Td) as a time between the electrical impulse and 10% of the contraction; Contraction time (Tc) as a time between 10 ... The sensor contains a tip designed to register muscle's contraction. Muscle contraction is induced with twitch type (one ... evidence-based measurement method that precisely measures the speed of muscle contraction under isometric conditions. It is ...
Isotonic contractions place muscles in a constant tension but the muscle length changes, while isometric contractions hold a ... Tetanic contraction can exist in a variety of states, including isotonic and isometric forms-for example, lifting a heavy box ... In comparison with tetanic contraction in an isometric state (such as holding up a heavy box for several minutes), it differs ... A fused tetanic contraction is the strongest single-unit twitch in contraction. When tetanized, the contracting tension in the ...
The exercise even performed at maximum voluntary isometric contraction did not increase pain in one study in people with ...
In the case of fatigue in a 30-second isometric contraction, the first window may be the first second, the second window might ... After a period of maximum contraction, the nerve's signal reduces in frequency and the force generated by the contraction ... and isometric contractions), vertical jump heights, other field tests of lower body power, reduced throwing velocities, reduced ... reducing their inhibition of contraction and leaving potassium ions as the only restricting influence on muscle contractions, ...
In cardiac physiology, isometric contraction is an event occurring in early systole during which the ventricles contract with ... 274-275, Oxford University Press, Oxford Isovolumetric Contraction on Isovolumetric Contraction on medical- ... The isovolumetric contraction phase lasts about 0.05 seconds, but this short period of time is enough to build up a ... Therefore, an isovolumetric contraction is one in which the volume of fluid remains constant.[citation needed] Isovolumetric ...
To help with lifts, the concept of isometric contraction, during which the length of muscle remains the same during contraction ... Local intra-articular hip pain has been shown to inhibit gluteal contraction potential, meaning that hip pain could be a main ... ISBN 978-0-9876504-0-5. Choi, Sil-ah (April 2015). "Isometric hip abduction using a Thera-Band alters gluteus maximus muscle ... Being less common than lumbar hyperlordosis[citation needed], hypolordosis (also known as flatback) occurs when there's less of ...
The patient's isometric contraction has the correct amount of force, the correct direction of effort (away from the restrictive ... As the patient performs an isometric contraction, the following physiologic changes occur: Golgi tendon organ activation ... For example, contraction of a muscle on the right side leads to relaxation of the same muscle on the left side. A 2015 Cochrane ... Joint mobilization using muscle force: Use muscle contraction to restore range of motion in a joint. Oculocephalogyric reflex: ...
The murmur increases with squatting and decreases with standing and isometric muscular contraction such as the Valsalva ... As a consequence of this stenosis, the left ventricle must generate a higher pressure with each contraction to effectively move ...
were able to maintain isometric peak torque in subjects who performed daily maximal isometric contractions of the knee ... Eccentric contractions are actions of the muscle in which force is generated while the muscle is lengthening, as opposed to the ... After 17 days of spaceflight or bed rest, no significant measurable changes occurred in maximal isometric calf strength, force- ... Bamman and colleagues observed losses of 18, 17, and 13% in concentric, eccentric, and isometric plantar flexor peak torque, ...
... they include isometric contraction (no movement), isotonic contraction and concentric contraction (shortening). Eccentric ... Eccentric contraction may result in delayed onset muscle soreness however; the contraction itself does not cause muscle damage ... the biceps are in a state of contraction to control the rate of descent of the dumbbell). An eccentric contraction is one of ... Eccentric contractions use less energy and actually absorb energy that will be used as heat or elastic recoil for the next ...
Certain parts of the game consist of platforming in isometric view. All the non-player characters (some voice-acted) exist in ... Petit, Carolyne (April 8, 2009). "There's compelling dungeon-crawling action to be found here, hiding amid tedious puzzles and ...
The Ascent is presented from an isometric view overlooking the character(s). It is a twin-stick shooter. It includes the ... there's the fact that so much of the game is designed to feel like servitude... Your bosses insult you when you go on your task ...
The greatest isometric active tension is developed when a muscle is at its optimal length. In most relaxed skeletal muscle ... Since the next ventricular contraction occurs at its regular time, the filling time for the LV increases, causing an increased ... Due to the Frank-Starling mechanism, the next ventricular contraction is more forceful, leading to the ejection of the larger ... More than 30 years before the development of the sliding filament model of muscle contraction and the understanding of the ...
However, an isometric or aerial top-down perspective is common in party-based RPGs, in order to give the player a clear view of ... Ishaan (23 January 2011). "Here's How Xenoblade And Metroid: Other M Did In Japan". Siliconera. Retrieved 2 September 2011. ... But this genre incorporates strategic gameplay such as tactical movement on an isometric grid. Tactical RPGs tend not to ... Later, in the middle to late 1990s, isometric, sprite-based RPGs became commonplace, with video game publishers Interplay ...
It received a score of 8.2 out of 10 from IGN, who stated, "If you've played the game on the Xbox, there's not much for you ... Early versions used the Myth engine and isometric perspective. The project had the initial working title Armor, but was changed ...
It uses an isometric projection camera view, somewhat similar to the squad-level real-time tactics video game in the mold of X- ... As a terrorist there's no specific persona the player assumes. Instead, they merely control all terrorist units during a ... with the player issuing orders to individual avatars from a static isometric view of the level. Many of Police Quest: SWAT 2's ...
The Commodore 64 Home Companion said that "there's lots of education hidden in" the level editor, concluding that Lode Runner " ... Lode Runner 2 (1998), a game with isometric 3D gameplay. Lode Runner (1998), a compilation game for PlayStation, which includes ...
... is a role-playing video game that is played from an isometric perspective. Both returning and ... Makuch, Eddie (January 10, 2019). "God Of War, Spider-Man Lead DICE Awards; Here's All The Nominees". GameSpot. Retrieved ... Video games with isometric graphics, Windows games, Xbox Cloud Gaming games, Xbox One games, Versus Evil games). ...
For the muscles to respond explosively, the eccentric contraction is then quickly switched to the isometric (when the downward ... The strong eccentric contraction prepares the muscles to switch to the concentric contraction in an explosive manner for ... In the eccentric contraction, the muscles are involuntarily lengthened, while in the concentric contraction, the muscles are ... This in turn would bring about a forced eccentric contraction which was then immediately switched to a concentric contraction ...
... that is independent of the coordinate chart one uses to perform the contraction. Physically, this means that if the invariant ... has its roots in manifold theory where determining if two Riemannian manifolds of the same dimension are locally isometric (' ...
Although using isometric perspective, the structure and gameplay are similar. Nintendo attempted to take legal action against ... This remained undiscovered for 26 years until Dyer revealed it on his blog, stating that "there's an Easter egg, but it's ...
It is played from an isometric perspective with only one player, who controls one of 15 playable characters through story ... "There's a goofy pleasure in seeing animated Lego figures pantomime scenes from the movies, and the game's puzzles and battles ...
The initially theory consisted of Haupl-Andersen's ideas who believed that Isometric Muscular Contraction caused by Myotatic ...
... (1983), Baby Pac-Man (1983), and Professor Pac-Man (1984). Other games include the isometric Pac-Mania (1987), the side ... They said there's "more to the game than at first appears" but criticized the sound as a drawback, saying it's "good for awhile ...
"There's obviously a strong inherent fan base in place due to the massive popularity of the books. With the release of the ... and is played from an isometric three-quarter top-down view. Gameplay focuses on turn-based combat, and at various points, all ... There's a huge responsibility to get this aspect of the game right, because I know there are fans out there who will count the ... and would be played from an isometric three-quarter top-down view. By then, the publishing had transitioned from Sierra to VU ...
... with a rotatable isometric three-quarter top-down view. At the beginning of the game, character stats are preset, with the ... but there's still not enough that's new to truly keep pushing the genre forward. There could be more weapons and more ...
The Treasures of King Nole was an early isometric RPG that combined the gameplay of an open-world action RPG with an isometric ... "Here's How Much Dragon Quest IX Sold Overseas". 27 January 2011. Pereira, Chris (29 July 2014). "Bravely Default's Strong Sales ... That same year, Arcus Odyssey by Wolf Team (now Namco Tales Studio) was an action RPG that featured an isometric perspective ... em up fighting gameplay with fantasy role-playing and introduced an isometric perspective. That same year, Enix released a ...
Typically, the number of muscle contractions is an order of magnitude greater than the number of action potentials sent to the ... relatively large myofibril diameters lead to increased diffusion times of Ca2+.Under isometric twitch experiments, asynchronous ... First, two antagonistic muscles can be configured with elastic structures such that the contraction of one muscle stretches the ... Typically, the rate of mechanical contraction is an order of magnitude greater than electrical signals. Although they achieve ...
The game marks a major shift in the series by using 3D graphics and real-time combat, replacing the 2D isometric graphics and ... Barlow, Anthony (October 29, 2008). "IGN Fallout 3 Review-There's Been Some Changes". The PlayStation Network. Archived from ...
Muscle contraction can be eccentric (velocity of contraction v < 0 {\displaystyle v. 0 {\displaystyle v>0} ) or isometric ( v ... then eccentric contraction force is lowered proportionally to the value of activation; The maximum isometric force is a ... force-velocity characteristic we notice that muscle force in an eccentric contraction is higher than the maximum isometric ... is the maximum isometric force. Our choice of the cost function is based on the supposed optimization mechanisms carried on by ...
Oshry, Dave (16 April 2012). "Theme Hospital in HD is Glorious! Here's How To Get It Working". Gameranx. Complex. Archived from ... Video games with isometric graphics, Windows games, Video games with custom soundtrack support, Krisalis Software games, ...
Piasecki explains "if there's a windmill next to a farmer, the program has to check whether that miller has the capacity to ... Video games with isometric graphics, Windows games). ...
During isometric contractions the series elastic component is under tension and therefore is stretched a finite amount. Because ... Therefore, the higher the load applied to the muscle, the lower the contraction velocity. Similarly, the higher the contraction ... is the velocity of contraction F 0 {\displaystyle F_{0}} is the maximum isometric tension (or load) generated in the muscle a ... Muscle contraction Hill, A.V. (October 1938). "The heat of shortening and dynamics constants of muscles". Proc. R. Soc. Lond. B ...
U.S. Department of State representative Richard Boucher said in interview to The Guardian: "There's a strong appearance of ... the shutdown of TV-6 and bidding farewell before the channel switched to TV-6's logo on a white background with an isometric ...
A lens space is a quotient of the 3-sphere (or (2n + 1)-sphere) by a free isometric action of Zk. Manifold. A topological ... and the contraction of x {\displaystyle x} by y {\displaystyle y} is zero. Chart Cobordism Codimension. The codimension of a ...
... performing the deadlift exercise using maximal isometric force (MIF) and MIF normalized by body mass (ratioMIF) in two barbell ... The present results showed that the maximal isometric deadlift exercise at 75% LLH (midthigh) improves subsequent jump ... primary purpose of this study is to examine the effect of two different deadlift barbell height positions on maximal isometric ... Different Barbell Height Positions Affect Maximal Isometric Deadlift Force and Subsequent Squat Jump Performance in ...
RCAF (Royal Canadian Air Force Fitness program), Bob Richards isometric contraction program, health, fitness, physical ... Sams, B. (1967). A Comparison Of The RCAF Physical Fitness Program And Bob Richards Isometric Contraction Program In Relation ... A Comparison Of The RCAF Physical Fitness Program And Bob Richards Isometric Contraction Program In Relation To Selected ... A Comparison Of The RCAF Physical Fitness Program And Bob Richards Isometric Contraction Program In Relation To Selected ...
Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. S. Ohara, T. Nagamine, A. ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. In: Journal of Clinical ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. / Ohara, S.; Nagamine, T.; ... Electrocorticogram-electromyogram coherence during isometric contraction of hand muscle in human. Journal of Clinical ...
The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric ... contractions and remain less understood. A number of molecular theories have been put forth … ... An eccentric contraction involves the active lengthening of muscle under an external load. ... The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric ...
... concentric muscle contraction muscle function tests isometric muscle contraction muscle tetanus isotonic contraction scisense ... concentric muscle contraction muscle function tests isometric muscle contraction muscle tetanus isotonic contraction scisense ... Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function research 7 years ... Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function research 7 years ...
CO-CONTRACTION AND ISOMETRIC EXERCISES IN PATIENTS WITH CHRONIC FROZEN SHOULDER were more effective in reducing pain. ... The purpose of this study was to find out the comparison of Thera-band, co-contraction and isometric exercises on shoulder pain ... The objective was to find out the comparison between the effects of Thera-band, co-contraction and isometric exercises in ... Three study groups, group A, B and C received Thera-band, co contraction and isometric exercises respectively. Patients were ...
Subjects with neck and shoulder pain also showed no significant changes in the LF/HF ratio of HRV responding to isometric ... In addition, the low frequency / high frequency (LF/HF) ratio of HRV significantly increased during isometric exercise in the ... Subjects with neck and shoulder pain showed lower oxygenation and blood flow of the trapezius muscles responding to isometric ... The participants performed three sets of isometric exercise in an upright position; they contracted their trapezius muscles ...
Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function research from ... Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function researchAndy ... Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function research ... Beyond Isometric Twitch: Utilizing lengthening, shortening and isotonic contraction tests for muscle function research ...
Isometric Contraction * Muscle Contraction * Muscle, Skeletal / physiology* * Psychomotor Performance / physiology * Rotation * ... For EG, a significant increase of the peak torques was measured in isometric, eccentric, and concentric conditions (P , 0.5). ...
Fourteen young adults (6 men and 8 women; 27.1 +/- 9.1 years) performed three sets of 16-s isometric contractions with the ... isometric) lower limb target-matching contractions at low and high intensities. ... Isometric contraction; Lower limb muscles; Force fluctuations; Sex differences ... Control of steady lower limb contractions involves cortical and subcortical motor areas in both men and women and provides ...
Isotonic & isometric contraction Rajesh Goit. Aerobics exercise for healthy adult Adlynn Mazlan ...
The maximum isometric muscular contraction was recorded. Three trials were obtained for each mouse and averaged. ... was verified via light microscopy with confirmation of a majority of sarcomere containing cells and visible contraction. ...
Kay_ISB_2015_Acute_Effects_Of_Contract_Relax_Stretching_Static_Stretching_And_Isometric_Contractions_On_Mu ... (214kB). ... Acute effects of contract-relax stretching, static stretching and isometric contractions on muscle-tendon mechanics ... The Iso condition included 4 x 5 s ramped maximal isometric plantar flexor contractions performed in the anatomical position, ... Conclusion: While similar ROM increases occurred after isometric contractions and static stretching, changes in muscle and ...
34] A significant improvement in lower extremity, maximum, voluntary isometric contraction was seen. ...
... amplitudes and contraction levels on lower limb muscles during graded isometric contractions superimposed on whole body ... amplitudes and contraction levels on lower limb muscles during graded isometric contractions superimposed on whole body ...
The effect of local skin cooling before a sustained, submaximal isometric contraction on fatigue and isometric quadriceps ... The effect of local skin cooling before a sustained, submaximal isometric contraction on fatigue and isometric quadriceps ... The effect of local skin cooling befre a sustained, submaximal isometric contraction on fatigue and isometric quadriceps ... The effect of local skin cooling befre a sustained, submaximal isometric contraction on fatigue and isometric quadriceps ...
Effect of Hip Abduction Maximal Voluntary Isometric Contraction on Lumbar Motion and Power Output During the Back Squat ... Effect of Hip Abduction Maximal Voluntary Isometric Contraction on Lumbar Motion and Power Output During the Back Squat. ... Kubo, K., Kanehisa, H. and Fukunaga, T. (2001). Effects of different duration isometric contractions on tendon elasticity in ... The purpose of this study was to examine the potential PAP effect of a hip abduction maximal voluntary isometric contraction ( ...
Phosphate uptake in rat skeletal muscle is reduced during isometric contractions.. *K. A. Abraham, R. Terjung ... Influence of ribose on adenine salvage after intense muscle contractions.. *R. Zarzeczny, J. Brault, K. A. Abraham, C. Hancock ... The data imply that P( i) uptake in skeletal muscle is acutely modulated during contractions and that decreases in P(i) uptake ... The data indicate that the adenosine content of skeletal muscle is increased by contraction, and support the concept that ...
Example strengthening exercises: Isometric groin contraction. Hip adduction using a resistance band. ... Sitting hip flexion - isometric.. *Example stretches: Hip flexor stretch. Laying quadricep stretch. Standing quadricep stretch. ... Example Strengthening Exercises: Isometric hip adduction. Hip adduction using a resistance band. ... Example strengthening exercises: Isometric hip flexion. Standing hip flexion with a resistance band. ...
Effect of New Zealand blackcurrant extract on isometric contraction-induced fatigue and recovery.Oct 14, 2020. ... New Zealand blackcurrant extract enhances muscle oxygenation during repeated intermittent forearm muscle contractions in ...
Test measurements with this MC sensor on the biceps brachii muscle under isometric conditions (elbow angle 90°) showed a high ... This MC sensor is based on a novel principle whereby muscle tension is measured during muscle contractions. During the ... individual linear correlation between the isometric force and MC signal amplitudes (0.97 ≤ r ≤ 1). The measurements also ... This paper presents a new muscle contraction (MC) sensor. ... Voluntary isometric contractions were performed with the elbow ...
Short versus long isometric contractions. Eur J Appl Physiol Occup Physiol 71: 337-341, 1995.. * Cited Here , ... the initial 10 contractions. The training protocol involved 4 sets of bilateral knee extensions to failure at 50% of 1RM and ... Yasuda T, Brechue WF, Fujita T, Shirakawa J, Sato Y, Abe T. Muscle activation during low-intensity muscle contractions with ... 85) compared 3 sets of unilateral plantar flexor contractions (20% of 1RM; 30 repetitions each set; 1-minute rest intervals ...
On and off oxygen uptake kinetics; Drop jump; Intermittent exercise; Maximal voluntary isometric contraction; Oxygen ... test and the maximal voluntary isometric contraction (MVIC) test for the lower limbs, and a progressive test until exhaustion; ...
... innervation can be tested indirectly by evaluation of isometric contraction of the muscle. To test muscle function, have the ... Contraction of viable muscle is assessed by palpation of the lateral edge of the latissimus dorsi from the posterior axilla to ... If muscular contraction is not elicited by any of the above techniques, assume that muscle has been denervated, which results ...
long isometric contractions. Eur J Appl Physiol 1995; 71: 337-341 * 59 Stone MH, Sands WA, Carlock J, Callan S, Dickie D, ... 9 Beltman JGM, van der Vliet MR, Sargeant AJ, de Haan A. Metabolic cost of lengthening, isometric and shortening contractions ... 44 Maffiuletti NA, Martin A. Progressive versus rapid rate of contraction during 7 week of isometric resistance training. Med ... 34 Kubo K, Kanehisa H, Fukunaga T. Effects of different duration isometric contractions on tendon elasticity in human ...
Isometric contractions of the extremities to augment venous return may be helpful. Increasing sodium and fluid intake may ...
A Secret Obstacle Has Been Blocking Your Full Strength Potential - Heres How the ISOCHAIN Can Help You Smash Through Your ... Isometrics: Bodybuildings "Cheat Code" Ah-isometrics! Strength training without movement. Its a method championed through the ... Isometric Super-Power, the Top 10 Reasons to Use the Isochain in your Strength Training Do you remember strength? Real strength ... Infinite Isometrics - Hebbs Rule: The Law of Strength Training Hebbs rule is not just fundamental to strength gain-its ...
You could also refer to isometric contractions as abdominal bracing.. This type of contraction requires a lot of energy because ... Eccentric Contractions. Now, the opposite of a concentric contraction is an eccentric contraction, which happens when a muscle ... Concentric Contractions. Concentric contractions are used to generate movement. The best example of concentric contraction in ... Isometric Contractions. Some exercises are able to generate enough force that it becomes equal to the external load without ...
Mountain climbing; tug-of-war; isometric contraction; weight training. Muscular endurance is the ability to continue ... Mountain climbing; tug-of-war; isometric contraction; weight training. Muscular endurance is the ability to continue ... For example, if endurance training (high repetition, low load contractions) is undertaken the muscular system will undergo ...
  • Influence of ribose on adenine salvage after intense muscle contractions. (
  • This MC sensor is based on a novel principle whereby muscle tension is measured during muscle contractions. (
  • In general, there are three types of muscle contractions that will help you engage your core. (
  • However, do note that these muscle contractions are not exclusive of one another and that they often work alongside each other to help you complete various activities or exercises throughout the day. (
  • Now that you understand the three types of muscle contractions that occur, you can start to recognize them during your KILLER workouts and make small adjustments to ensure you're engaging your core. (
  • isometric muscle contractions and action potentials were recorded. (
  • Re-oxygenation reduced contracture and indirect muscle contractions resumed. (
  • Nimmo began to reason that the bones of the body are passive structures whose alignment and movements are controlled by muscle contractions and tonus. (
  • These include movement plane, the muscles and joints you're using, the type of muscle contractions (concentric, eccentric, and isometric), and technical proficiency. (
  • Subjects with neck and shoulder pain showed lower oxygenation and blood flow of the trapezius muscles responding to isometric exercise, compared with asymptomatic subjects. (
  • 27.1 +/- 9.1 years) performed three sets of 16-s isometric contractions with the ankle dorsiflexor muscles at 10, 30, 50, and 70 % of maximal voluntary contraction (MVC). (
  • A perfect example of an isometric contraction is when you use your core muscles to balance your body and hold still during a high plank. (
  • Correct handstand position requires many of your muscles to engage in an isometric muscle contraction, while keeping your body perfectly balanced. (
  • Isometric muscle contraction means that your muscles are contracting without moving a joint. (
  • Netfit explains that eccentric contractions help keep motions smooth and normally occur as a braking force against concentric contraction, which allows for the protection of joints and muscles against injury. (
  • Structural neural correlates of physiological mirror activity during isometric contractions of non-dominant hand muscles. (
  • Anodal tDCS of the ipsilateral primary motor cortex prolongs the latency of physiological mirror activity during unilateral isometric contractions of intrinsic hand muscles. (
  • It is possible to consider that the proprioceptive changes in the modulation of muscle contraction in individuals with GJH may influence the pattern of electrical activity on masticatory muscles associated to a clinical state of TMD. (
  • The primary movers in the military press are the shoulders, triceps, upper chest and upper back muscles, while your core and lower body muscles have the job of keeping the body stable through isometric contraction. (
  • Using their technique, a contraction of contralateral muscles is recorded in a conscious subject after transcranial electrical stimulation (TES). (
  • Isometric exercises, the kind where you contract large muscles without actually moving the body part, may help reduce blood pressure in healthy people, a study shows. (
  • But the creators of the Shake Weight claim the vibration creates isometric force on the muscles to hold steady, working the muscles more than regular concentric-eccentric movements. (
  • The purpose of this study was to examine the potential PAP effect of a hip abduction maximal voluntary isometric contraction (MVIC) on lumbar motion and power output during the barbell back squat. (
  • The electromyographic (EMG) normalization (often to maximum voluntary isometric contraction [MVIC]) is used to control for interparticipant and day-to-day variations. (
  • This study developed a technique to predict the MVIC EMG from submaximal isometric voluntary contraction EMG. (
  • Using the ratios between the MVIC EMGs and submaximal isometric voluntary contraction EMG data values established on day 1, and the day 2 submaximal isometric voluntary contraction EMG data values, the day 2 MVIC EMGs were predicted. (
  • MVC (maximal voluntary isometric contraction) force, knee extension maximal power output and RFD (rate of isometric force development) increased in all conditions with no between condition differences. (
  • Exercise training protocol consisted of five 3-min bouts of IHG exercise at 30% of maximum voluntary contraction separated by 5 min rest periods. (
  • Isotonic contraction is slightly more complex - the muscle is preloaded, and then prevented from stretching any further. (
  • Because the stimulated muscle can shorten, lifting the load, the force that the muscle encounters is "isotonic" - that is, throughout contraction the force is constant. (
  • Isometric contraction is perhaps analogous to the contraction of say the left ventricle during the brief period when all the valves are closed, and isotonic contraction is a poor approximation of contraction of the ventricle as it forces blood into the aorta, against pressure. (
  • This brings us to a very important point: the isometric length-tension curve helps us greatly when we examine isotonic shortening. (
  • If we examine the length of the muscle after an isotonic contraction, and the corresponding tension, we find this tension to be the same as the tension we would have obtained had we performed an isometric contraction at this final length! (
  • In other words, the isometric curve provides a limit for the isotonic performance of the muscle. (
  • A dynamic (or isotonic) contraction occurs when the force generated by the muscle causes movement in the joint. (
  • There are two phases to an isotonic contraction. (
  • But more formally, bodyweight training is any type of physical training that uses isometric or isotonic exercise to strengthen or develop muscle. (
  • An eccentric contraction involves the active lengthening of muscle under an external load. (
  • The net result of these eccentric contraction characteristics and responses appears to be a novel adaptive signal within the neuromuscular system. (
  • Now, the opposite of a concentric contraction is an eccentric contraction, which happens when a muscle lengthens to help resist external force that is greater than the force that the muscle can generate. (
  • If we use crunches as our example again, the eccentric contraction occurs when you're lowering your body back down to the floor. (
  • Following this, the hamstrings must undergo a transition from eccentric contraction to a brief isometric contraction at heel strike before contracting concentricly to assist the glutes in hip extension. (
  • All participants performed maximal squat jumps (MSJ) at 90º of knee flexion before (pre-test) and after 4-min (post-test) performing the deadlift exercise using maximal isometric force (MIF) and MIF normalized by body mass (ratio MIF ) in two barbell height positions (25% and 75% of the lower limb height, LLH) in a randomized and counterbalanced order. (
  • The present results showed that the maximal isometric deadlift exercise at 75% LLH (midthigh) improves subsequent jump performance of the squat jump recreationally-trained men. (
  • The characteristics of eccentric contractions are associated with several acute physiological responses to eccentrically-emphasised exercise. (
  • Subsequently, the high levels of muscular strain with such exercise can induce muscle damage which is rarely observed with other contraction types. (
  • In addition, the low frequency / high frequency (LF/HF) ratio of HRV significantly increased during isometric exercise in the control group, whereas there were no significant changes in the pain group. (
  • Subjects with neck and shoulder pain also showed no significant changes in the LF/HF ratio of HRV responding to isometric exercise, which would imply a reduction in sympathetic nervous activity. (
  • Also, there's more than one way to engage your core during exercise depending on the movement you're doing or the specific position you're trying to hold-think about the difference between planks and crunches. (
  • IMSEAR at SEARO: Effect of isometric exercise and mental stress on blood pressure--comparative effects of propranolol and labetalol. (
  • In one study a hand grip spring dynamo-meter was used for IHG (Isometric Handgrip) exercise training. (
  • This is the simplest type of isometric exercise, and it can be easily done at the office. (
  • Seems scientific sounding and therefore legit, except for the fact that you can create your own isometric force during any exercise by holding the movement at the most force-generating part of the movement. (
  • The best example of concentric contraction in the core is when you perform a crunch. (
  • Although maintenance of steady contractions is required for many daily tasks, there is little understanding of brain areas that modulate lower limb force accuracy. (
  • Functional magnetic resonance imaging was used to determine brain areas associated with steadiness and force during static (isometric) lower limb target-matching contractions at low and high intensities. (
  • Control of steady lower limb contractions involves cortical and subcortical motor areas in both men and women and provides insight into key areas for potential cortical plasticity with impaired or enhanced leg function. (
  • Mean PSC increased with contraction intensity in the contralateral primary motor area (M1), supplementary motor area, putamen, pallidum cingulate cortex, and ipsilateral cerebellum (p (
  • This study was concerned with a comparison of the Royal Canadian Air Force Fitness program and Bob Richards' isometric contraction program in relation to selected muscular and cardiovascular measures. (
  • If muscular contraction is not elicited by any of the above techniques, assume that muscle has been denervated, which results in an atrophic flap. (
  • For example, if endurance training (high repetition, low load contractions) is undertaken the muscular system will undergo specific changes that target. (
  • When a submaximal muscular contraction is followed by stretching of the same muscle, autogenic inhibition occurs, whereas reciprocal inhibition occurs when a submaximal muscular contraction is followed by stretching of the opposite muscle. (
  • Muscular contractions characterized by increase in tension without change in length. (
  • La ingesta de creatina parece mejorar un poco la fuerza muscular tanto en adultos jóvenes como en adultos mayores. (
  • La ingesta de creatina durante un máximo de 12 semanas parece mejorar la fuerza muscular en los adultos mayores. (
  • During maximal velocity contractions, as seen in competition, there is not enough time for maximal muscular force to be reached. (
  • 25. Mannion AF, Dolan P. Electromyographic median frequency changes during isometric contraction of the back extensors to fatigue. (
  • The objective was to find out the comparison between the effects of Thera-band, co-contraction and isometric exercises in chronic frozen shoulder patients in improving pain, range of motion and function. (
  • 36 patients with age ranged 30-70 years, diagnosed with chronic idiopathic frozen shoulder with limited shoulder ranges were randomly allocated to three groups, Group A,B,C performed Thera-band, co-contraction and isometric exercises respectively. (
  • The study concluded that co-contraction and isometric exercises were more effective in reducing pain while the Thera-band exercises showed a significant improvement in ranges. (
  • Some exercises are able to generate enough force that it becomes equal to the external load without lengthening or shortening the muscle-this is referred to as an isometric contraction. (
  • Eccentric contractions, also referred to as "negatives," are usually performed in strength training exercises that involve the slow lowering of a resistance or weight. (
  • Now it's time to choose the exercises in such a manner that there's a high likelihood of them achieving this and reaching their goals. (
  • What are Isometric Exercises? (
  • Isometric exercises can be done anytime, anywhere, and they don't require you to bend or lift. (
  • In a handful of studies, folks with normal blood pressure who did three 15 to 20 minutes sessions of isometric exercises every week for 10 weeks experienced more than a 10-point plunge in their systolic blood pressure. (
  • In the research, the three weekly sessions included doing multiple 2-minute rounds of isometric exercises like those, with 1 to 3 minute rests in between. (
  • This is one of the simplest forms of isometric exercises, and it can be performed daily. (
  • Most isometric exercises are not very tiring, but you must take it slowly if you're a beginner. (
  • Back in the 90s, isometric RPGs ruled supreme and they continued to be very popular all throughout the 2000s before gradually losing ground to first and third-person role-playing games. (
  • But just because isometric RPGs are no longer as popular as they used to be, that doesn't mean they are a thing of the past. (
  • Isometric RPGs have been experiencing a bit of a renaissance lately. (
  • To celebrate this new wave of interest in the venerable subgenre, we decided to put together a list of the best isometric RPGs of all time. (
  • The game still has some problems that prevent us from placing it higher on our list, but we would still recommend checking it out if you're a fan of post-apocalyptic/sci-fi isometric RPGs. (
  • Isometric RPGs tend to be associated with PC gaming but you can also find a few examples on consoles. (
  • Lush as its rendered backgrounds were, there was no room now for 2D or isometric RPGs. (
  • There's also the still ongoing debate whether hack and slashes are RPGs or not. (
  • The electrical activity of the quadriceps was recorded during muscle contraction as an objective index of fatigue. (
  • Isometric endurance of the quadriceps muscle is reduced in patients with COPD and the muscle oxidative profile is significantly correlated with muscle endurance. (
  • Hypoxia depressed twitch contractions and caused neuromuscular blockade in both groups. (
  • Accordingly, neural strategies controlling eccentric contractions also differ with a greater, and possibly distinct, cortical activation observed despite an apparently lower activation at the level of the motor unit. (
  • There were minimal sex differences in brain activation across the isometric motor tasks indicating men and women were similarly motivated and able to activate cortical motor centers during static tasks. (
  • By not working against any resistance, it's extremely difficult to produce an isometric contraction in the spinal erector musculature and the lats that's strong enough to lock the lumbar spine into extension during the movement. (
  • Phosphate uptake in rat skeletal muscle is reduced during isometric contractions. (
  • The data imply that P( i) uptake in skeletal muscle is acutely modulated during contractions and that decreases in P(i) uptake rates, in combination with expected increases in P (i) efflux, exacerbate the net loss of phosphate from the cell. (
  • 9 Beltman JGM, van der Vliet MR, Sargeant AJ, de Haan A. Metabolic cost of lengthening, isometric and shortening contractions in maximally stimulated rat skeletal muscle . (
  • The primary purpose of this study is to examine the effect of two different deadlift barbell height positions on maximal isometric force and subsequent maximal squat jump performance in recreationally-trained men. (
  • Cerebellar transcranial direct current stimulation improves maximum isometric force production during isometric Barbell squats. (
  • Isometric Contraction Improves Jump Performance" by Jonathan Montano, Elizabeth Torossian et al. (
  • 10 Bimson L, Langdown L, Fisher JP, Steele J. Six weeks of knee extensor isometric training improves soccer related skills in female soccer players . (
  • Isometric contraction occurs where the muscle is prevented from shortening. (
  • A static (or isometric) contraction occurs when a muscle generates force while the joint angle remains the same. (
  • Brain areas associated with force steadiness and intensity during isometric ankle dorsiflexion in men and women. (
  • Contraction of viable muscle is assessed by palpation of the lateral edge of the latissimus dorsi from the posterior axilla to the iliac crest and by contralateral comparison. (
  • 3 Alegre LM, Ferri-Morales A, Rodriguez-Casares R, Aguado X. Effect of isometric training on the knee extensor moment-angle relationship and vastus lateralis muscle architecture . (
  • 11 Bogdanis GC, Selima E, Methenitis S, Veligekas P, Tsoukos A, Terzis G. Changes in muscle strength and vertical jump performance after short-term isometric training at different knee angles . (
  • Range of motion in hip flexion and isometric strength in knee flexion were measured. (
  • You could also refer to isometric contractions as abdominal bracing. (
  • Conclusion: While similar ROM increases occurred after isometric contractions and static stretching, changes in muscle and tendon stiffness were distinct. (
  • Holding for as long as you can demands muscle endurance in an isometric contraction. (
  • Data indicate that adenine salvage rates were essentially unaltered during recovery from intense contractions, and ribose supplementation did not affect subsequent muscle force production after 60 min of recovery. (
  • Concentric contractions typically use more energy compared to the other types of contractions, but they also generate less force. (
  • This type of contraction requires a lot of energy because it generates a lot of force-this force is often used to inhibit movement rather than to create it or slow it down. (
  • Increased recovery rates of phosphocreatine and inorganic phosphate after isometric contraction in oxidative muscle fibers and elevated hepatic insulin resistance in homozygous carriers of the A-allele of FTO rs9939609. (
  • Fitness fans have many decisions in fitness equipment for energy coaching in all its facets - weight, resistance, isometric and built-in. (
  • In examining the above curve, note that the curve reflects the sum of the tension generated due to muscle contraction and the resting tension. (
  • The curve commonly used to assess inotropy is the isometric length-tension curve - a positive inotropic stimulus shifts the curve up and to the left, and a negative stimulus down and right. (
  • Endothelial function, vascular superoxide, and nitric oxide production/bioavailability in aortas from fructose-fed rats and age-matched controls treated with or without apocynin were assessed using isometric tension studies in organ chambers. (
  • I prefer to think of it as "pulling tension into your body," because there's not really any "slack" in the bar. (
  • The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric contractions and remain less understood. (
  • Isolated uterine arteries were examined for AT 1 R and AT 2 R expression and isometric contraction/relaxation. (
  • Kay, A. D. , Husbands-Beasley, J. and Blazevich, A. J. (2015) Acute effects of contract-relax stretching, static stretching and isometric contractions on muscle-tendon mechanics. (
  • The reduction in tendon stiffness and increase in ROM detected following the Iso condition have important methodological implications as these data indicate that the performance of contractions 'on stretch' during PNF stretching may not be needed. (
  • Forceful contraction of the calf muscle may rupture (completely tear) the Achilles tendon. (
  • Inverse relationship between amplitude and latency of physiological mirror activity during repetitive isometric contractions. (
  • Modifying PNF stretching to perform the contraction phase in the anatomical, rather than highly stretched position, removes the need for partner assistance, decreases the likelihood of inducing pain, tissue damage and muscle strain injury during the technique, which may enhance PNF's suitability and practicality for athletic and clinical populations. (
  • Our results suggest that Rac1 coordinates with RhoA to increase MLC phosphorylation by inactivation of CPI-17/MYPT1 phosphatase, which decreases MLCP activity thus promoting MLC phosphorylation and cell contraction. (
  • To increase maximum strength, IST should be performed at 80-100% MVC with sustained contraction of 1-5 s, and total contraction time of 30-90 s per session, while adopting multiple joint angles or targeted joint angle. (
  • Those maximum contraction 'tight' planks are something that I can probably start to move beyond. (
  • Associated to these changes, joint instability in GJH patients can alter the modulation of muscle contraction. (
  • Therefore, the effects of contract-relax proprioceptive neuromuscular facilitation (CR) stretching, static stretching (SS) and maximal isometric contraction (Iso) interventions were studied in 17 healthy human volunteers. (
  • This review used a narrative summary of findings from studies that focused on isometric strength training (IST), covering the training considerations that affect strength adaptations and its effects on sports related dynamic performances. (