Cardiac OutputHemodynamicsExercise TestExercisePhysical ExertionExercise ToleranceOxygen ConsumptionExercise TherapyPhysical EnduranceHeart RateAnaerobic ThresholdPulmonary Gas ExchangeMyocytes, CardiacRestBicyclingHeartPhysical FitnessMuscle, SkeletalErgometrySpectrometry, GammaLactic AcidOxygenBlood PressureStroke VolumeRunningHeart FailureTime FactorsSportsPhysical Education and TrainingElectrocardiographyRegional Blood FlowMetabolic EquivalentLegPhysical Conditioning, AnimalRespirationArrhythmias, CardiacCardiovascular Physiological PhenomenaCarbon DioxideCardiac Surgical ProceduresRespiratory Function TestsDeath, Sudden, CardiacAltitudeBlood Gas AnalysisRespiratory MechanicsWork of BreathingVentricular Function, LeftEchocardiographyRespiratory MusclesAthletesMuscle FatigueAnalysis of VarianceCatecholaminesPulmonary VentilationSports MedicineLactatesEnergy MetabolismAdaptation, PhysiologicalForced Expiratory VolumeAnoxiaRespiratory Physiological PhenomenaTreatment OutcomeHeart DiseasesCardiac Pacing, ArtificialMyocardiumAngina PectorisCardiomegalyCoronary DiseaseMuscle StrengthVascular ResistanceDyspneaCardiac CatheterizationMyocardial ContractionAdrenergic beta-AntagonistsCardiac TamponadeHeart VentriclesCross-Over StudiesWalkingReference ValuesFollow-Up StudiesSingle-Blind MethodProspective StudiesResistance TrainingHorsesPulmonary CirculationLung Volume MeasurementsNorepinephrineMuscle ContractionDouble-Blind MethodAtenololSpectroscopy, Near-InfraredMuscle Stretching ExercisesAcclimatizationVital CapacityChronic DiseaseEpinephrineBlood VolumePostureHeart ArrestMotor ActivityArm