(HealthDay)—It's safe for older adults to run marathons, a new study finds.
Researchers at the University of Manitoba in Canada tested marathon participants over age 50 before and after their 26.2-mile run. Using blood tests, ultrasounds and scans up to three months later, they found the runners had temporary heart effects similar to those seen in runners aged 18 to 40.
The effects included a brief increase in blood indicators of heart damage and temporary swelling and weakness in the right side of the heart immediately after the marathon. All of these effects disappeared within a week.
"There was no evidence of permanent heart damage from repeated marathon running in individuals over the age of 50," primary study author Davinder Jassal, an associate professor of medicine, radiology and physiology, said in a university news release.
The study was published online in August in the Journal of Cardiovascular Magnetic Resonance.
Aging populations in Canada and the United States mean there's a growing number of people over age 50 who exercise regularly, the researchers noted. For example, the number of older people taking part in marathons has doubled over the past two decades.
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More information: The U.S. National Heart, Lung, and Blood Institute offers a guide to physical activity.