Effects of training on cardiac output

Cardiac output is defined as the amount of blood ejected from the heart during each minute. As with stroke volume; cardiac output is considered only the amount ejected from the left ventricle. The right ventricle will eject an equal amount of blood during the same time.

Cardiac output is calculated by multiplying the heart rate by the stroke volume. A normal cardiac output value for a person at rest is between 5 to 6 L per minute. Untrained athletes can increase their cardiac output fourfold during exercise, to approximately 20 L/min, by increasing their heart rates and stroke volumes. Trained athletes can increase their cardiac output even more because training increases maximum stroke volume. It is very important for the athletes to have an increased cardiac output during exercise because it increases the amount of oxygen and blood glucose that can be delivered to the muscles during each minute and the amount of carbon dioxide and lactic acid that can be removed from them at the same time.

Resting cardiac output does not increase as there is no reason for this; the demand for oxygen remains the same, but the heart becomes stronger and more efficient in the way it supplies the blood. Other benefits of increasing your cardiac output with exercise are: improved blood pressure and health of the arteries, and a boost in your energy levels, mood and endurance.

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