Isometric ContractionMuscle ContractionMuscle, SkeletalMusclesMuscle FatigueElectromyographyMuscle, SmoothMuscle Fibers, SkeletalIsotonic ContractionTorqueElectric StimulationMyocardial ContractionUterine ContractionMuscle, Smooth, VascularElbowMuscle RelaxationRecruitment, NeurophysiologicalMotor NeuronsMuscle ProteinsCalciumSarcomeresKneeBiomechanical PhenomenaMyosinsMuscle StrengthTime FactorsPapillary MusclesQuadriceps MuscleVasoconstrictionPhysical EndurancePsoas MusclesRabbitsMuscle SpindlesPhysical ExertionMusculoskeletal Physiological PhenomenaMyofibrilsVolitionGuinea PigsTracheaPotassium ChlorideMyographyMuscle DevelopmentStress, MechanicalDose-Response Relationship, DrugRana temporariaMuscle Fibers, Fast-TwitchPhenylephrineAcetylcholineMyosin Light ChainsPhosphocreatineHindlimbRats, WistarAdenosine TriphosphateLegElasticityThighModels, BiologicalCatsRats, Sprague-DawleyAction PotentialsMuscle Fibers, Slow-TwitchTendonsExerciseVasoconstrictor AgentsAnuraEvoked Potentials, MotorAnkle JointMuscle WeaknessActinsNorepinephrineMasseter MuscleReflex, StretchAorta, ThoracicMuscle Strength DynamometerMovementMyocytes, Smooth MuscleReflexDogsHand StrengthHandMotor CortexPeristalsisFingersRana esculentaMuscle DenervationMuscle TonusGastrointestinal MotilityArmAnalysis of VarianceForearmWeight-BearingEnergy MetabolismElbow JointUrinary BladderNeck MusclesKineticsHeart RateAdaptation, PhysiologicalCarbacholMuscle, Striated