Isometric ContractionElectromyographyMuscle ContractionMuscle, SkeletalMuscle FatigueTorqueIsotonic ContractionElbowRecruitment, NeurophysiologicalMusclesElectric StimulationKneeBiomechanical PhenomenaMotor NeuronsMuscle Fibers, SkeletalMuscle StrengthMyocardial ContractionUterine ContractionSarcomeresPhysical EnduranceQuadriceps MuscleMusculoskeletal Physiological PhenomenaMuscle RelaxationVolitionTime FactorsMuscle, SmoothMyosinsPsoas MusclesPhysical ExertionPapillary MusclesLegAnkle JointMyographyThighEvoked Potentials, MotorCalciumNeural ConductionRana temporariaVasoconstrictionMovementHandArmFingersMasseter MuscleMuscle Strength DynamometerTendonsAction PotentialsReflex, StretchPhosphocreatineKnee JointStress, MechanicalLaryngeal MusclesElasticityForearmMuscle SpindlesRana esculentaMotor CortexMyofibrilsWeight-BearingMuscle WeaknessRabbitsMuscle, Smooth, VascularPhenylephrineHand StrengthPotassium ChlorideReflexAnuraExerciseAnalysis of VarianceNeck MusclesPostureDose-Response Relationship, DrugAnkleModels, BiologicalFacial MusclesAdenosine TriphosphateCatsThumbElbow JointHindlimbGuinea PigsAcetylcholineFootFemoral NerveVasoconstrictor AgentsAdaptation, PhysiologicalRange of Motion, ArticularAorta, ThoracicTranscranial Magnetic StimulationMyosin Light ChainsNorepinephrineTracheaRats, WistarTask Performance and AnalysisFeedback, SensorySignal Processing, Computer-AssistedRats, Sprague-DawleyFasciculationTremorBupranolol