|Photo courtesy of NYTimes.com; Jonathan Knowles/Getty Images|
The results of the study, which were released only a few weeks ago in The Journal of Applied Physiology, showed that none of the younger atheletes and older non athletic athletes had fibrosis in their hearts. On the other hand, about half of the older lifelong athletes showed some sign of heart muscle scarring. "The affected men were, in each case, those who’d trained the longest and hardest. Spending more years exercising strenuously or completing more marathon or ultramarathon races was, in this study, associated with a greater likelihood of heart damage."
There have been other studies like this one in Germany and with lab rats. The bottom line is, the question of whether intense, lifelong endurance exercise is harmful to the heart has been around for ages. As the Times points out, it most often arises whenever a lifelong athglete who is supposedly healthy suffers a major heart attack.
After reading the article, it appears to me there is some small, but significant, link between lifelong endurance training and damage to the heart. That does not mean that everyone should just quit exercising. This study targeted people who exercised vigorously every day and ran/cycled/swam countless marathons, triathalons, etc...
Because the study has been done before (with some loopholes that were covered in this most recent study) and the results have been mildly consistent, I believe that there is a connection between endurance training and heart damage, and that lifelong athletes should be aware of these risks. For now, however, until the science of excessive exercise is better perfected, we should all keep exercising regularly, but with a little more caution. Pay attention to what your body is telling you, and see a doctor if your heart starts acting up during or after exercise. Otherwise, just keep swimming! (Or running, or bicycling... you get the gist.)
Read more at http://well.blogs.nytimes.com/2011/03/09/when-exercise-is-too-much-of-a-good-thing/?hp.