SpasmMuscle RelaxationMusclesMuscle, SkeletalMuscle, SmoothMuscle SpasticityNeck MusclesMuscle ProteinsMuscle ContractionMuscle, Smooth, VascularMuscle Fibers, SkeletalSpasms, InfantileMuscle DevelopmentCervical AtlasOccipital BoneElectromyographyNeuromuscular AgentsSpinal Cord InjuriesMuscle FatigueMotor NeuronsHemifacial SpasmBotulinum Toxins, Type ARelaxation TherapyMitochondria, MuscleMuscle Fibers, Fast-TwitchMuscle DenervationMuscle Fibers, Slow-TwitchMuscular AtrophyIsometric ContractionMyostatinMyocytes, Smooth MuscleQuadriceps MuscleOculomotor MusclesFacial MusclesMuscle, StriatedMuscle SpindlesPapillary MusclesRespiratory MusclesMuscle WeaknessCoronary VasospasmAbdominal MusclesTracheaMuscle CellsHindlimbElectric StimulationNitric OxideSarcopeniaTime FactorsExerciseVasodilationMasseter MuscleAcetylcholineMasticatory MusclesRabbitsEsophageal Spasm, DiffuseCalciumMuscle StrengthIntercostal MusclesRats, Sprague-DawleyGlycogenResistance TrainingCyclic GMPSatellite Cells, Skeletal MusclePhysical EndurancePectoralis MusclesGuinea PigsVasodilator AgentsHypertrophyPhysical ExertionDeuteroporphyrinsMuscular DiseasesDose-Response Relationship, DrugNitroprussideNeuromuscular JunctionLegNeuromuscular BlockadeHSP20 Heat-Shock ProteinsBiomechanical PhenomenaPsoas MusclesMyofibrilsMuscle Relaxants, CentralNeuromuscular Nondepolarizing AgentsRats, WistarTemporal MuscleEndothelium, VascularPenisAortaInsulinRegional Blood FlowSignal TransductionCells, CulturedRelaxationAgingAorta, ThoracicCreatineErgonovineOrgan SizeAdaptation, PhysiologicalOxygen ConsumptionPharyngeal Muscles