The endurance of the pump.
D004032:Diet; D004777:Environment; D006321:Heart / Q000502:physiology*; D006331:Heart Diseases / Q000209:etiology; D006801:Humans; D007199:Indians, South American; D008019:Life Style; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption; D005082:Physical Exertion