Background

Athlete’s heart is a cardiac condition often seen in active individuals. It refers to the normal changes a heart undergoes in people who regularly participate in strenuous, prolonged exercise. This condition may result from aerobic exercise or weight training, commonly when training extends longer than one hour per day.

Various physiological adaptations occur in the heart of an individual with this condition. When participating in exercise, the heart must pump more blood faster to supply the body’s working muscles with oxygen and nutrients. When an individual participates in consistent vigorous activities, the heart adapts to improve its function and efficiency. The left ventricle (the bottom left chamber of the heart) increases in both thickness and size, the amount of blood pumped out of the heart increases, and the resting heart rate is lowered.

Symptoms

The changes seen with athlete’s heart do not result in any symptoms experienced by the individual. However, there are a few signs that can be indicative of the condition:

• A slower heart rate (bradycardia)
• An extra heart sound (usually heard with stethoscope)
• Occasionally, a heart murmur, which is a sound produced by your heart heard with a stethoscope (systolic ejection murmur)

The few signs above may only be detected by a medical professional. These are normal changes in the heart from exercise and they are not a significant health risk. It is still important to eliminate any other dangerous diagnoses that may produce similar signs such as aortic stenosis, hypertension, ischemic heart disease, and hypertrophic obstructive cardiomyopathy.

Sports Medicine Evaluation and Treatment

If your doctor observes any of the signs above, an evaluation and certain medical tests may be performed. Your doctor may perform the following:

• A thorough personal and family medical history and physical exam
• An evaluation of personal exercise and activity level
• Electrocardiogram (ECG/EKG): Small round stickers, called leads, will be attached to your chest. These leads are connected to the EKG machine, which will monitor your heart’s electrical activity. Your physician will provide an interpretation of the results, and the test takes about five minutes to complete.
• Echocardiogram (Echo): This is a test that uses sound waves, or ultrasound, to provide a visual image of your heart. A handheld device will be placed over your chest, providing a live picture on a screen. This allows the doctor to examine your heart’s size, shape, and blood flow.
• Exercise Stress Test: This test involves walking or jogging on a treadmill while connected to an EKG machine. This allows your doctor to gather information about how your heart works during physical activity. Since your heart pumps faster and harder while exercising, certain problems may be revealed only with exertion.

Treatment

Treatment is not required for individuals diagnosed with athlete’s heart. No evidence has been found of any long-term danger from the changes regular exercise may cause to the heart.

Return to Play

Clearance from a qualified physician to exclude any other heart problems may be required. Since the condition is an adaptation of the heart muscle to the increased demand from exercise, a period of deconditioning will reverse the heart’s anatomy back to its normal size and function. The average time it takes to complete this process is approximately three months.

Prevention

Studies have concluded that an average of one hour of exercise per day or greater may result in the development of athlete’s heart. There are usually no symptoms, so the condition is usually only found incidentally at a sports physical or doctor’s visit.

AMSSM Member Authors
Michael Israel, MD, CAQSM and Austin Cole

References
“Athletic Heart Syndrome.” Merck Manual Professional. Dec. 2005. http://www.merckmanuals.com/professional/cardiovascular-disorders/sports-and-theheart/athlete-s-heart. Retrieved January 7, 2017.
Maron, BJ; Pelliccia, A. “The heart of trained athletes: cardiac remodeling and the risks of sports, including sudden death”. Circulation. 10 Oct. 2006. 114 (15):1633–44.
Baggish, A; Malissa, W. “Athlete’s Heart and Cardiovascular Care of the Athlete”.
American Heart Association. 13 June, 2011. http://circ.ahajournals.org/content/123/23/2723. Retrieved January 16, 2017.