Athletic PerformanceExercise ToleranceExercise TestSportsPerformance-Enhancing SubstancesDoping in SportsAthletesPhysical EnduranceSports MedicineExerciseFlatfootRunningAnabolic AgentsPhysical ExertionExercise TherapyOxygen ConsumptionFootballMuscle, SkeletalDietary SupplementsPhysical Conditioning, AnimalBicyclingAnaerobic ThresholdHorse DiseasesTask Performance and AnalysisHorsesMuscle FatigueLactic AcidPsychomotor PerformanceHeart RateDyspneaPulmonary Gas ExchangeHemorrhageLung Diseases, ObstructiveTime FactorsBreathing ExercisesPhysical FitnessCarnosinePhysical Education and TrainingRespiratory Function TestsAltitudeDouble-Blind MethodWalkingMuscle StrengthEnergy MetabolismRespiratory MusclesPulmonary VentilationAnalysis of VariancePulmonary CirculationRestIntermittent ClaudicationCross-Over StudiesOxygenInspiratory CapacityFatigueAdaptation, PhysiologicalReproducibility of ResultsFontan ProcedureCardiovascular Physiological PhenomenaPulmonary Disease, Chronic ObstructiveGlycogenHemodynamicsMuscle ContractionDietary CarbohydratesSwimmingRespirationHeart FailureLactatesForced Expiratory VolumeQuadriceps MuscleBody WeightPlasma VolumeCardiac OutputSingle-Blind MethodDehydrationLegCitrate (si)-SynthaseBody Temperature RegulationCarbon DioxideTreatment OutcomeSensitivity and SpecificityNeuropsychological TestsCognitionStroke VolumeVital Capacity