Isometric ContractionMuscle, SkeletalElectromyographyMuscle ContractionTorqueMuscle StrengthMuscle FatigueQuadriceps MuscleRecruitment, NeurophysiologicalMusclesElbowKneeMotor NeuronsVolitionElectric StimulationFemoral NerveBiomechanical PhenomenaTime FactorsHandIsotonic ContractionLegKnee JointMuscle, SmoothPhysical EnduranceMuscle Fibers, SkeletalPhysical ExertionMaximal Voluntary VentilationThighMuscle WeaknessMyocardial ContractionExerciseMuscle RelaxationHand StrengthMuscle, Smooth, VascularUterine ContractionSarcomeresEvoked Potentials, MotorCalciumRange of Motion, ArticularMuscle ProteinsExercise TherapyMyosinsPapillary MusclesPsoas MusclesVasoconstrictionFingersMovementMuscle Strength DynamometerMuscle SpindlesForearmElbow JointRabbitsAnkle JointMusculoskeletal Physiological PhenomenaMotor CortexReflex, StretchStress, MechanicalPhosphocreatineTendonsReflexArmThumbMyographyRana temporariaGuinea PigsH-ReflexPotassium ChlorideTracheaHeart RateAction PotentialsAdaptation, PhysiologicalMyofibrilsAnalysis of VarianceMuscle Fibers, Fast-TwitchVoluntary ProgramsTranscranial Magnetic StimulationPhenylephrineAcetylcholineDose-Response Relationship, DrugWeight-BearingHindlimbMyosin Light ChainsRespiratory Muscles