Quadriceps MuscleThighMuscle, SkeletalMusclesMuscle StrengthMuscle FatigueMuscle ContractionMuscle WeaknessTorqueIsometric ContractionKneeKnee JointFemoral NerveElectromyographyMuscle Fibers, SkeletalMuscle ProteinsMuscle Strength DynamometerReflex, StretchElectric Stimulation TherapyPatellaMuscle, SmoothExerciseLegBiomechanical PhenomenaMuscular AtrophyAnterior Cruciate LigamentKnee InjuriesMuscular DiseasesPatellar LigamentMuscle, Smooth, VascularRespiratory MusclesMuscle Fibers, Slow-TwitchJoggingMuscle DevelopmentTendonsArtificial OrgansMitochondria, MuscleElectric StimulationImmobilizationPhysical EnduranceMuscle SpindlesOsteoarthritis, KneePatellofemoral JointRange of Motion, ArticularOxygen ConsumptionMyostatinWeight LiftingPhysical ExertionMuscle Fibers, Fast-TwitchJoint InstabilityWeight-BearingBicyclingExercise TestGaitPatellofemoral Pain SyndromeMuscle DenervationTime FactorsArthroplasty, Replacement, KneeMotor NeuronsExercise TherapyRecovery of FunctionPulmonary Disease, Chronic ObstructiveMyocytes, Smooth MuscleAdaptation, PhysiologicalAbdominal MusclesMuscle RelaxationLactic AcidParaplegiaHypertrophyBiopsyNeck MusclesPulmonary Stretch ReceptorsOculomotor MusclesGlycogenRegional Blood FlowAnalysis of VarianceMuscle, StriatedOrgan SizePapillary MusclesFemurMotor ActivityPain MeasurementPainAgingMasseter MuscleMuscle CellsMasticatory MusclesH-ReflexHindlimbMyofibrilsIntercostal MusclesFacial MusclesPhysical Conditioning, HumanMechanoreceptorsDiaphragmOxygenMusculoskeletal Physiological PhenomenaMovementMuscle SpasticityMagnetic Resonance Imaging