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Athlete's Heart


Robert S. McKelvie

, MD, PhD, Western University

Last full review/revision Oct 2020| Content last modified Oct 2020

Athlete's heart refers to the normal changes that the heart undergoes in people who regularly do strenuous aerobic exercise (for example, higher intensity running or bicycling) and also in those who do higher intensity weight training exercise (weight lifting).

In a person with athlete's heart

  • The heart is larger.
  • The heart walls are thicker.
  • The heart chambers are somewhat larger.

This increase in size and thickening of walls allows the heart to pump substantially more blood per heartbeat. The larger volume of blood with each heartbeat allows the heart to beat more slowly, which results in a slower, stronger pulse (which can be felt at the wrist and elsewhere on the body) and sometimes in a heart murmur. Heart murmurs are specific sounds created as blood flows through the valves of the heart. Although heart murmurs can also be a sign of a heart valve disorder, murmurs are perfectly normal in an athlete's heart and are not dangerous. The heartbeat of a person with athlete's heart may be irregular at rest but becomes regular when exercise begins. Blood pressure is virtually the same as in any other healthy person. Heart changes in women are typically less than those in men of the same age, body size, and level of training.

The heart changes that take place in an athlete's heart resemble those that can occur in certain heart disorders. For example, the heart can enlarge in hypertrophic cardiomyopathy and heart failure. Murmurs can occur in heart valve disorders, and an irregular pulse can indicate an abnormal heart rhythm. The main differences between athlete's heart and an abnormal heart is that in athlete's heart

  • The heart and its valves function normally.
  • The person does not have an increased risk of a heart attack or other heart disorder.

The person has no symptoms. Doctors usually suspect athlete's heart during routine screening or when the person is being evaluated for unrelated symptoms.

Diagnosis of Athlete's Heart

  • Electrocardiography

Most athletes do not require extensive testing, but doctors usually do electrocardiography (ECG) because it is important to ensure that the person does not have a heart disorder. A variety of electrical changes in the heart are detectable on an ECG. These changes would be considered abnormal in a person who is not an athlete but are perfectly normal in an athlete.

If the person has chest pain or other symptoms of a heart disorder, more extensive testing is needed, such as echocardiography, exercise stress testing, and occasionally, cardiac magnetic resonance imaging (CMR). These tests evaluate the structure and function of the heart.

Treatment of Athlete's Heart

  • No treatment needed

No treatment is needed. When an athlete stops training, athlete's heart slowly disappears—that is, heart size and heart rate tend to return gradually to those of the nonathlete. This process may take weeks or months to occur. Sometimes an athlete needs to decrease or stop training for a few months to determine whether the changes disappear or further evaluation for a heart disorder is needed.

Athlete's heart is not thought to affect health in any way. The rare sudden death of an athlete is usually due to underlying heart disease that was not previously detected rather than to any danger resulting from athlete's heart.

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