It’s never too late to start a moderate exercise regimen in out-of-shape America. But Dr. Paul Thompson, chief of cardiology and co-physician-in-chief of the Hartford HealthCare Heart & Vascular Institute, has spent much of his professional life studying effects on runners who perhaps exercise too much.
“It looks like you get the most benefit from exercise when you go from nothing to something,” he said during a recent appearance on FoxCT. “The question is if there are increasing problems if people do too much exercise.”
Dr. Thompson, himself a runner with a 30-marathon resume that includes a 2:28:25 time in the 1972 Boston Marathon, published a study in 1979 on 18 men and women who died while running or immediately. Thirteen of the runners showed signs of heart disease. A 2011 Swedish study showed that males entered in a marathon cross-country ski race who had either completed the race the most times in the previous decade or finished with the fastest times were more likely than others to develop atrial fibrillation. (A-fib, when the heart’s upper chambers beat out of sync with the lower chambers, increases the risk of stroke by up to 500 percent.)
The cause of death by exercise is defined clearly by age, says Dr. Thompson.
“If you’re over the age of 35,” he said, “it’s almost always narrowing of the coronary arteries from cholesterol.”
About 30 percent of them had previous symptoms, he said.
“A lot of them ignore chest discomfort,” Dr. Thompson said. “One of the things that’s ignored most frequently is discomfort in the top of the stomach. People think they’re having an ulcer or they’ve got heartburn — but that’s your heart until you prove it otherwise. So check it out with your physician.”
The death of younger runners during exercise is most often caused by congenital conditions of the heart muscle or coronary arteries. The hearts of serious athletes even look different. They’re larger and, because each beat injects more blood, the heart rate is slower.
“We don’t think that’s deleterious or dangerous in any way,” said Dr. Thompson.
A study of former Olympians earlier this year, in fact, showed that changes in the size of a serious runner’s heart do not cause long-term damage to the heart. The potential health benefits of exercising regularly, it turns out, overwhelm any possible dangers.
Hear that, out-of-shape America?
Most people prepared to run a marathon should not have a second thought, said Dr. Thompson. It’s the sedentary population that’s at greater risk of heart disease.
“Overexercise is not our problem in the United States,” he said. “Even standing up during the day reduces your risk of heart disease.”