Mumbai Marathon by through my eyes only on flickr
A study published recently by British researchers suggests that engaging in years of strenuous physical activity—such as marathons or ultramarathons—is associated with a greater likelihood of heart damage, The New York Times reports.
Researchers observed a group of men aged 50 and above who had been part of the British national or Olympic distance running and rowing teams, as well as members of the 100 Marathon Club (runners that have completed 100 marathons). Magnetic resonance images of these men's hearts were compared to those from two other groups—similarly aged non-endurance athletes and younger athletes—to determine any difference in fibrosis, or scarring of the heart's muscle tissue. The men who had engaged in years of endurance activity were associated with a greater likelihood of heart damage.
For most recreational athletes, however, the news should not be daunting.
“How many people are going to join the 100 Marathon club?” asked Dr. Paul Thompson, the chief of cardiology at Hartford Hospital in Connecticut and an expert on sports cardiology, in the New York Times article. “Not many. Too much exercise has not been a big problem in America. Most people just run to stay in shape, and for them, the evidence is quite strong that endurance exercise is good” for the heart, he said.
While it remains impossible to say at what point endurance exercise could begin to cause heart damage, absent the presence of heart arrhythmias or other signs of heart trouble, “I think it’s safe to say that you should keep it up,” Dr. Thompson said.