Me too, until a professional dropped dead during a race up in Queensland about 30?? y ago. I've just spoken to sis's husband and he said he isn't suffering any damage from his running. He stopped at about 70 y, just because he wasn't getting the fun out of it any more. He ran 8 marathons including one in S Korea, Boston and Toronto twice. over a period of 19 years. And ran every night for exercise, and enjoyment with a friend.
February 12, 2018
Why too much running is bad for your heart
[...]
From couch potatoes to marathon runners, how running impacts your heart
If a heart attack occurs, a marathon runner is more likely to survive than his or her sedentary counterpart, but the same can be said of people who engage in other kinds of regular activity. Exercising regularly puts your heart in a better place to survive a cardiac event.
But endurance running has actually been linked to poor heart health. Studies have found that the hearts of lifelong male endurance athletes may contain more plaque or other signs of heart problems, such as scarring and inflammation, than the hearts of less active men of the same age.
[...]
The right amount of running
A combination of both aerobic exercise and strength exercise is best. Exercise helps preserve weight loss, which is good for the heart. Exercise doesn’t prevent plaque buildup or heart blockages, but it does work to make us “tougher” and more likely to survive serious medical illnesses and accidents.
Running is the most efficient source of aerobic exercise, hence its popularity. But only to a certain point .. http://www.wfaa.com/video/news/too-much-running-may-be-bad-for-your-heart/287-8046995 . Approximately 15-20 miles per week appears to be ideal — shorter distances and varying speeds are healthier for your heart than endurance running.
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