A warning for marathon runners: a group of Greek doctors found long-distance runners have stiffness of large arteries. That suggests high-intensity exercise may actually be bad for your heart.
The findings were presented Saturday, March 13, at the American College of Cardiology's annual scientific session, in Atlanta.
The doctors say marathon-style running can lead to hardening of the arteries, high blood pressure, heart attacks and even death.
The runners in the study trained about 10 to 19 hours a week, for periods ranging from about 2 to 20 years, the researchers said. Standard marathons are 26.2 miles from start to finish.
The researchers said there may be several explanations for the stiffer arteries found in marathoners. One is that extreme exercise may place repeated and excessive stress on the artery wall, leading to its fatigue, said Dr. Charalambos Vlachopoulos, of Athens Medical School, Hippokration Hospital, and a co-investigator of the study.
Here's how one physician puts it: "The cardiovascular system is like a sports car engine. If you do not use it, it will decay. But if you run it too fast or too long, you might burn it out."
For more information about heart health, visit the U.S. National Heart, Lung, and Blood Institute.
