Muscle ContractionMuscle, SkeletalMusclesIsometric ContractionMuscle Fibers, SkeletalMuscle FatigueMuscle ProteinsElectromyographyMuscle, SmoothElectric StimulationVolitionTroponin CTroponinMuscle CrampMuscle, Smooth, VascularMuscle Fibers, Fast-TwitchMuscle DevelopmentMyosinsRabbitsCalciumMuscle Fibers, Slow-TwitchMuscle DenervationTropomyosinTorqueMitochondria, MuscleMotor NeuronsHandwritingMuscular AtrophyHindlimbEvoked Potentials, MotorRegional Blood FlowRectus AbdominisMuscle RelaxationMuscle SpindlesHandMotor CortexPhysical Conditioning, AnimalRats, WistarUterine ContractionMyocardial ContractionPhysical ExertionMyofibrilsRats, Sprague-DawleyTime FactorsBiomechanical PhenomenaMyocytes, Smooth MuscleGlycogenQuadriceps MuscleTendonsMuscular DiseasesMuscle WeaknessMuscle, StriatedHindlimb SuspensionNeck MusclesLegSatellite Cells, Skeletal MuscleOculomotor MusclesCatsMyosin Heavy ChainsPapillary MusclesRespiratory MusclesPhosphocreatineMuscle CellsAnkle JointPhysical EnduranceMyostatinAbdominal MusclesRunningOrgan SizeGuinea PigsOxygen ConsumptionDiaphragmNeuromuscular JunctionMyocardiumMasticatory MusclesRNA, MessengerBody WeightRecruitment, NeurophysiologicalFacial MusclesVasoconstrictionInsulinExerciseAdenosine TriphosphateMasseter MuscleAgingCells, CulturedSarcomeresEnergy MetabolismMusculoskeletal Physiological PhenomenaDose-Response Relationship, DrugTracheaIsotonic ContractionVoluntary ProgramsMyoblastsActinsMuscular Dystrophy, AnimalIntercostal MusclesMice, Inbred C57BLReflexAdaptation, Physiological