A growing body of research suggests that too much running isn’t a good thing.
If running 15 miles a week is heart-healthy, running 45 miles a week gives you a cardiovascular system three times as clean and strong, right?
Uh, maybe not.
At least, not according to a new study that adds to a growing body of research on excessive endurance exercise.
You’ve heard of the runner’s high. Researchers now want you to hear about runner’s plaque: coronary artery plaque.
In short: Running superlong distances for many years might backfire on you.
“Years of extreme exercise efforts appear to erase some benefits you get from moderate exercise, so that your risk of heart disease, of dying of coronary disease, is the same as a sedentary person,” said Dr. James O’Keefe, preventive cardiologist at St. Luke’s Hospital in Kansas City, Mo.
O’Keefe said the new study found that men who were marathon runners for 25 years had 62 percent more plaque buildup in their coronary arteries than men who were sedentary but were similar to the runners in other respects, including age.
That increased quantity of plaque in the marathoners’ arteries included both hard, or calcified, plaque and the more dangerous soft, fatty plaque. (The latter is the kind that can be predisposed to rupture and cause a heart attack.)
O’Keefe is co-author of the paper about the study, which appeared in the latest issue of Missouri Medicine, the journal of the Missouri State Medical Association. The study was conducted by Dr. Robert Schwartz and colleagues at the Minneapolis Heart Institute Foundation.
An unwavering advocate of exercise and its health benefits, O’Keefe said the new study adds weight to the idea that the potent benefits of exercise are “dose-dependent.”
That is, the right amount matters.
Being sedentary is unhealthy. Regular, moderate exercise bestows long-term benefits. But while logging huge numbers of miles and running marathons can keep you thinner, lower your risk for type 2 diabetes and offer other benefits, it appears the subsequent wear and tear on the heart is a potential drawback, O’Keefe said.
That information might be music to the ears of 3-milers, but it’s cautionary news for marathoners and ultramarathoners, at least those who have been at it for years.
Dr. John C. Hagan III is one of them.
“I started running in 1967, and those were the days when the police would stop you and ask you what you were running from,” said Hagan, a Kansas City area ophthalmologist.
A lifelong runner, Hagan participated in more than 25 half-marathons, four marathons and two half-Ironman Triathlons. He typically ran 30 to 40 miles a week.
So he was surprised when, at age 61, he was diagnosed with atrial fibrillation, a heart rhythm problem. After learning more about runners with heart problems, he finally decided to get a heart scan for his coronary artery calcium score, an indicator of heart artery plaque.