Quadriceps MuscleThighMuscle, SkeletalMusclesMuscle StrengthMuscle FatigueMuscle WeaknessMuscle ContractionTorqueIsometric ContractionKneeKnee JointFemoral NerveMuscle ProteinsMuscle Strength DynamometerMuscle Fibers, SkeletalElectromyographyElectric Stimulation TherapyPatellaLegExerciseMuscle, SmoothMuscular AtrophyAnterior Cruciate LigamentBiomechanical PhenomenaMuscular DiseasesKnee InjuriesPatellar LigamentMuscle, Smooth, VascularRespiratory MusclesMuscle Fibers, Slow-TwitchJoggingMuscle DevelopmentArtificial OrgansMitochondria, MuscleTendonsImmobilizationPhysical EnduranceElectric StimulationOsteoarthritis, KneePatellofemoral JointOxygen ConsumptionRange of Motion, ArticularMyostatinWeight LiftingJoint InstabilityPhysical ExertionBicyclingMuscle Fibers, Fast-TwitchWeight-BearingExercise TestGaitPatellofemoral Pain SyndromeArthroplasty, Replacement, KneeMuscle DenervationExercise TherapyTime FactorsRecovery of FunctionCattlePulmonary Disease, Chronic ObstructiveMotor NeuronsAbdominal MusclesMyocytes, Smooth MuscleMuscle SpindlesAdaptation, PhysiologicalLactic AcidBiopsyParaplegiaMuscle RelaxationHypertrophyNeck MusclesRegional Blood FlowOculomotor MusclesGlycogenAnalysis of VarianceMuscle, StriatedOrgan SizeFemurPapillary MusclesAgingPain MeasurementMotor ActivityPainMuscle CellsMasseter MuscleFacial MusclesMasticatory MusclesPhysical Conditioning, HumanHindlimbIntercostal MusclesOxygenMusculoskeletal Physiological PhenomenaDiaphragmTreatment OutcomeH-ReflexMagnetic Resonance ImagingRuptureSatellite Cells, Skeletal MuscleLactatesMyofibrils