Past studies found that endurance athletes, like marathon runners, have scarring in their heart muscles as well as coronary plaques which can cause a heart attack. So is too much exercise bad for us?

But first, it’s important to note that most of those earlier studies were small and showed a limited view of an athlete’s heart. They also did not follow athletes years later to see if the scarring and plaques precipitated heart attacks or contributed to shorter lives.

The Study

A new study, conducted by scientists at the Cooper Institute in Dallas, looked into these findings a bit deeper to see if scarring and plaques in endurance athletes actually contributed to major health problems.

The study grouped male athletes (most in their 50s) into three groups of exercisers: extreme exercisers (5 hours or more/week), somewhat less extreme athletes, and athletes who exercised half as much as the extreme group.

The Findings

It’s true, extreme exercisers developed more plaques than those less active. But by checking death records a decade or so later, the study found that the extreme exercisers had less risk of dying than those less active exercisers with similar plaque levels. So yes, lots of exercise can increase plaque levels, but it also lessens the the likelihood of a heart attack caused by said plaque.

One hypothesis stems from the fact that these plaques in endurance athletes might be more dense and stable making them less likely to break apart and cause a heart attack. More research will need to be conducted for any definitive conclusions.

What We’ve Learned

As always, all middle-aged athletes should look out for heart-related symptoms. But this recent study says that endurance runners with plaque or high calcium scores can safely continue to exercise.

Source: New York Times

Sonja Stilp M.D. is a doctor and founder of RISE. She is a board-certified physical medicine and rehabilitation physician with fellowship training in interventional spine and sports medicine.  Dr. Stilp has advanced training in regenerative medicine and orthobiologics for the treatment of spine and sports injuries. Schedule an appointment to meet with Dr. Stilp at RISE in Boulder, Colorado.