Muscle ContractionMuscle, SkeletalMusclesMuscle Fibers, SkeletalIsometric ContractionMuscle ProteinsTroponin CTroponinMuscle FatigueMuscle, SmoothMyosinsTropomyosinRabbitsCalciumElectric StimulationMuscle, Smooth, VascularMuscle DevelopmentRegional Blood FlowMuscle Fibers, Fast-TwitchMuscle Fibers, Slow-TwitchMitochondria, MuscleMuscle DenervationMuscle RelaxationElectromyographyMyocytes, Smooth MuscleSatellite Cells, Skeletal MuscleMuscle SpindlesMuscle, StriatedMuscular AtrophyMyofibrilsMyocardial ContractionNeck MusclesQuadriceps MuscleOculomotor MusclesMuscle CellsMuscular DiseasesMuscle WeaknessHindlimbUterine ContractionPapillary MusclesRespiratory MusclesTime FactorsAbdominal MusclesRats, Sprague-DawleyGlycogenRats, WistarSarcomeresActinsMyosin Heavy ChainsFacial MusclesGuinea PigsDiaphragmPhysical ExertionMasticatory MusclesCells, CulturedMyoblastsBiomechanical PhenomenaTracheaMotor NeuronsMasseter MuscleSarcoplasmic ReticulumPsoas MusclesMyocardiumVasoconstrictionIntercostal MusclesNeuromuscular JunctionRNA, MessengerAdenosine TriphosphateExerciseKineticsInsulinMuscular Dystrophy, AnimalPhosphorylationDose-Response Relationship, DrugModels, BiologicalPotassium ChlorideSignal TransductionMyoblasts, SkeletalAcetylcholineGlucoseSarcolemmaPhysical EndurancePectoralis MusclesOxygen ConsumptionMyoD ProteinCaffeineMyostatinPhosphocreatineTorqueMyosin Light ChainsRegenerationDogsMice, Inbred mdxMice, Inbred C57BLRyanodine Receptor Calcium Release ChannelMolecular Sequence DataLegEnergy MetabolismMembrane PotentialsIsotonic Contraction