How is cardiac output regulated during exercise

J Physiol 89 , — Heart-rate recovery immediately after exercise as a predictor of mortality. N Engl J Med , — Autonomic control of heart rate by metabolically sensitive skeletal muscle afferents in humans. J Physiol , — Vagally mediated heart rate recovery after exercise is accelerated in athletes but blunted in patients with chronic heart failure. J Am Coll Cardiol 24 , — Autonomic mechanisms of muscle metaboreflex control of heart rate.

J Appl Physiol 74 , — Reflex control of the circulation during exercise: chemoreflexes and mechanoreflexes. J Appl Physiol 69 , — Physiology News Magazine. The stroke volume increases because of increased ventricular contractility, manifested by an increased ejection fraction and mediated by sympathetic nerves to the ventricular myocardium.

End-diastolic volume increase slightly. Because of this increased filling, the Frank-Starling mechanism also contributes to the increased stroke volume stroke volume increases when end-diastolic volume increases. Cardiac output can be increased to high levels only if the peripheral processes favoring venous return to the heart are simultaneously activated to the same degree.

Factor promoting venous return:. Control of sympathetic outflow. One or more discrete control centers in the brain are activated by output from the cerebral cortex. These centers become activated before the exercise started. Once exercise is started, local chemical changes in the muscle can develop, particularly during high levels of exercise, because of imperfect matching between blood flow and metabolic demands. Author: Healthwise Staff. Medical Review: Rakesh K.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content. To learn more about Healthwise, visit Healthwise. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated. Jump to content. For the body to function properly, the heart needs to pump blood at a sufficient rate to maintain an adequate and continuous supply of oxygen and other nutrients to the brain and other vital organs.

Cardiac output is the term that describes the amount of blood your heart pumps each minute. Doctors think about cardiac output in terms of the following equation:. Your stroke volume is the amount of blood your heart pumps each time it beats, and your heart rate is the number of times your heart beats per minute. A healthy heart with a normal cardiac output pumps about 5 to 6 liters of blood every minute when a person is resting.

During exercise, your body may need three or four times your normal cardiac output, because your muscles need more oxygen when you exert yourself. During exercise, your heart typically beats faster so that more blood gets out to your body.