Is too much exercise dangerous for your heart?
By Jonathan Benson
Engaging in too much strenuous physical activity can potentially take a very serious and lifelong toll on your health, suggests a new review published in the journal Mayo Clinic Proceedings. Dr. James O'Keefe of Saint Luke's Hospital of Kansas City and his colleagues evaluated a series of studies on cardiovascular injury caused by excessive endurance exercise and found that some people who exercise too much could develop permanent damage to their cardiovascular and arterial systems.
In the short term, extreme endurance training can cause temporary damage to the heart and arteries, which eventually heals during periods of recovery. But repeated and perpetual endurance training can cause chronic injuries in some people, resulting in patchy scarring of the heart, abnormal heart rhythms and coronary heart disease. If the body is not allowed to heal properly, in other words, and is constantly pushed to extreme levels, the consequences could be severe.
According to the data, 12 percent of runners who participate in marathons were found to have patchy myocardial scarring. Runners who participate in marathons were also found to be significantly more prone to developing coronary heart disease compared to runners that do not participate in marathons. Ultra-marathon running and professional cycling were also linked to a 500 percent increased rate of atrial fibrillation, also known as abnormal heart rhythms.
"A routine of daily physical activity can be highly effective for prevention and treatment of many diseases, including coronary heart disease, hypertension, heart failure, and obesity," says Dr. O'Keefe. "However ... a safe upper dose limit potentially exists, beyond which the adverse effects of physical exercise, such as musculoskeletal trauma and cardiovascular stress, may outweigh its benefits."
The issue pertains primarily to individuals that participate in so-called "extreme" endurance activities such as long-distance cycling trips or races, marathons, triathlons and even some of the popular team-based endurance events that include long periods of running, climbing, swimming and cycling. It does not necessarily apply to those engaging in routine exercises that promote health.
However, if not kept in check and at proper intervals, extreme endurance training of any kind can potentially lead to Phidippides cardiomyopathy, which is the name often used to describe sudden death due to fatal heart damage. This is presumably the condition that has taken the lives of several young teenagers in recent years, all of whom dropped dead suddenly while playing sports.Sources for this article include:http://www.pbs.org/newshour/rundown/2011/03/young-athletes-deaths-put-new-focus-on-heart-screening.htmlhttp://www.dailymail.co.uk/health/article-2154267/Excess-exercise-hurts-heart-cause-dangerous-long-term-harm-say-scientists.html