Muscle ContractionMuscle, SkeletalMuscle Fibers, SkeletalIsometric ContractionMusclesSarcomeresMuscle ProteinsTroponin CTroponinMuscle FatigueMyosinsElectric StimulationTropomyosinCalciumRabbitsMyofibrilsMuscle, SmoothRegional Blood FlowMuscle Fibers, Fast-TwitchMuscle DevelopmentMuscle, Smooth, VascularConnectinMuscle Fibers, Slow-TwitchMyocardial ContractionRana temporariaMuscle RelaxationMitochondria, MuscleAnuraMuscle DenervationElectromyographyTime FactorsTetanyHindlimbRana pipiensUterine ContractionMyocardiumBiomechanical PhenomenaDiaphragmIsotonic ContractionMyosin Heavy ChainsPsoas MusclesMuscular AtrophyRats, Sprague-DawleyMuscular DiseasesSatellite Cells, Skeletal MuscleRats, WistarMuscle SpindlesSarcoplasmic ReticulumMotor NeuronsActinsMuscle CellsActin CytoskeletonNeuromuscular JunctionGuinea PigsGlycogenPapillary MusclesModels, BiologicalKineticsStress, MechanicalElasticityAdenosine TriphosphateMyocytes, Smooth MuscleHeartMuscle, StriatedQuadriceps MuscleCaffeinePhysical ExertionCells, CulturedMyosin Light ChainsTracheaVasoconstrictionOculomotor MusclesMuscle TonusMuscular Dystrophy, AnimalCatsSarcolemmaDose-Response Relationship, DrugMuscle WeaknessMyoblastsAcetylcholineAction PotentialsPhosphorylationRana esculentaActomyosinNeck MusclesSignal TransductionMembrane PotentialsPotassium ChlorideRNA, MessengerPhosphocreatineInsulinTorqueDogsPotassiumExercisePhysical Conditioning, AnimalRespiratory MusclesTroponin IMice, Inbred C57BLEnergy Metabolism