Muscle FatigueAnoxiaFatigueOxygenMuscle, SkeletalMusclesMuscle ContractionCell HypoxiaIsometric ContractionMuscle ProteinsElectromyographyFatigue Syndrome, ChronicMuscle Fibers, SkeletalMyocardiumMental FatigueHeartMyocytes, CardiacQuadriceps MuscleMuscle, SmoothPhysical EnduranceRespiratory MusclesAbdominal MusclesMuscle, Smooth, VascularPapillary MusclesMuscle DevelopmentTime FactorsMyocardial ContractionElectric StimulationTorqueBackExerciseCalciumMuscle RelaxationMuscle WeaknessNeck MusclesMuscle StrengthCardiac OutputDiaphragmPhysical ExertionMuscle Fibers, Fast-TwitchMyofibrilsMuscle Fibers, Slow-TwitchSarcomeresIntercostal MusclesOxygen ConsumptionHypoxia, BrainMuscular DiseasesSarcoplasmic ReticulumBiomechanical PhenomenaLactic AcidHeart VentriclesArrhythmias, CardiacRabbitsElbowMitochondria, MuscleMuscle DenervationMyocytes, Smooth MuscleCells, CulturedExercise ToleranceAdaptation, PhysiologicalTroponin CRats, Sprague-DawleyRats, WistarCardiac Surgical ProceduresExercise TestFetal HypoxiaMuscle CellsTroponinCardiomegalyDeath, Sudden, CardiacTroponin IBicyclingPhosphocreatineRNA, MessengerAction PotentialsOculomotor MusclesInhalationRespirationFemoral NerveGlycogenAnalysis of VarianceDogsElectric Stimulation TherapyMotor NeuronsCardiac MyosinsHypoxia-Inducible Factor 1, alpha SubunitMyosin Heavy ChainsModels, BiologicalAdenosine TriphosphateRunningMuscle, StriatedEnergy MetabolismMuscle SpindlesSarcolemmaMolecular Sequence DataLumbosacral RegionLegMyographyHeart RateCardiomyopathies