Slide 2 of 9
The slide shows two important equations that help to explain the function and operation of the cardiovascular system. Cardiac output (Q) refers to the amount of blood pumped by the heart per minute. Cardiac output is equal to the heart rate times the stroke volume. During exercise both values increase to increase cardiac output and provide more oxygenated blood to the working muscles.
The amount of oxygen taken up and used by the body is refered to as VO2. It equals the cardiac output times the arterial-venous difference (amount of O2 taken up by the tissues). The higher cardiac output and higher avO2 difference cause the VO2 values to be higher during exercise.