Muscle, SkeletalMuscle ContractionMusclesMuscle Fibers, SkeletalIsometric ContractionMuscle ProteinsTroponin CMuscle, SmoothMuscle FatigueTroponinElectric StimulationMyosinsCalciumRabbitsTropomyosinMuscle DevelopmentMuscle, Smooth, VascularHindlimbMotor NeuronsMuscle Fibers, Fast-TwitchMuscle SpindlesRegional Blood FlowMuscle Fibers, Slow-TwitchMitochondria, MuscleCatsNeurons, AfferentUterine ContractionElectromyographyMyocardial ContractionMuscle DenervationMuscle RelaxationSatellite Cells, Skeletal MuscleMuscular AtrophyPeroneal NerveMyofibrilsSciatic NervePeripheral NervesNeural ConductionMuscular DiseasesTime FactorsDecerebrate StateRadial NerveSpinal Nerve RootsReflexRats, Sprague-DawleyRats, WistarQuadriceps MuscleMuscle CellsMyocytes, Smooth MuscleAction PotentialsSpinal CordGlycogenMuscle, StriatedGuinea PigsMuscle WeaknessSarcoplasmic ReticulumMyoblastsVasoconstrictionSympathetic Nervous SystemMyosin Heavy ChainsSarcomeresSural NerveLumbosacral RegionOculomotor MusclesPhysical ExertionPapillary MusclesNeck MusclesReflex, MonosynapticMyocardiumActinsDiaphragmCells, CulturedAfferent PathwaysReflex, StretchInsulinRNA, MessengerRespiratory MusclesAdenosine TriphosphateTracheaMyoblasts, SkeletalMechanoreceptorsKineticsDose-Response Relationship, DrugExerciseNeuromuscular JunctionIsotonic ContractionElectrophysiologyBiomechanical PhenomenaAbdominal MusclesPotassium ChlorideGlucoseAcetylcholineAxonsSignal TransductionSarcolemmaNerve FibersMotor Neurons, GammaPhosphorylationMuscular Dystrophy, AnimalCaffeine