Can Exercise Harm Your Heart?

From Tuber to Uber: Can Exercise Harm Your Heart? 

by Jennifer Anderson, MD, Ph.D., MS, MEd, FACC 

We all know that physical activity and exercise are good for you. Exercise lowers blood pressure, improves blood sugar/diabetes, lowers blood cholesterol, helps maintain optimal body weight, improves mental health, and can reduce your risk of and even reverse heart disease. But are there times when you should worry about causing your heart harm with exercise? 

This question may be answered on two different levels: the "couch potato" (or "tubers") who do not exercise, but maybe planning to initiate an exercise program to improve their health; versus the "uber" exercisers, which may include collegiate level athletes, elite/professional athletes, or competitive recreational athletes who exercise at a very high level. 

1. The Tubers. Statistically, the risk of suffering a sudden cardiac event while exercising is quite low; 1 per 1.51 million episodes of exercise in the Physicians' Health Study. In contrast, the benefits gained persist for hours following an exercise effort. For example, it has been shown that even a single bout of exercise will significantly decrease the absorption of fat into your blood after consuming a high-fat meal. Similarly, aerobic exercise has been shown to reduce blood pressure after just a few weeks of training. Positive gains like these are undoubtedly contributing factors to the overall reduced risk of heart disease observed in individuals who exercise compared to their sedentary counterparts. 

If you have not been physically active in the past and are planning to start a new exercise regimen, always discuss this with your doctor or health care provider. He or she may want you to complete a stress test prior to participation, particularly if you have risk factors for heart disease. 

2. The Ubers. It is no surprise that exercise training can affect the heart's structure and function quite drastically. After all, the heart is a muscle, right? These adaptations have collectively been coined as "athlete's heart," and can be readily observed through cardiac testing. Traditionally, these findings have been considered harmless and reversible. More recently, however, new findings may be more worrisome. Such observations include damage to the right ventricle of the heart, increased calcium in the arteries of the heart, and increased frequency of rhythm problems such as irregular heartbeat and atrial fibrillation. However, the clinical relevance of these observations remains unclear, as endurance athletes still enjoy overall healthier and longer lives, even if they have competed for years at the highest levels. Thus we need more data before we can make any definitive statements with confidence. 

In summary, while there might be some risks associated with exercise, the benefits far outnumber them. Symptoms such as unusual fatigue, heart skipping or racing sensations, lightheadedness, chest discomfort, breathing difficulty, and/or fainting during exercise should be immediately investigated by a qualified doctor and NEVER ignored... Tubers and Ubers alike. 

Dr. Jennifer S. Anderson, MD, Ph.D., MS, MEd, FACC is a board-certified cardiologist. She specializes in heart disease management and prevention, lipid management, therapeutic lifestyle interventions, as well as exercise and sports cardiology. She is a diplomate of the American Board of Clinical Lipidology and has completed advanced graduate degrees in nutrition and exercise physiology.  Her main office is located at Saint Alphonsus Eagle Health Plaza, 323 E Riverside Drive, Eagle.