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Dr. Paul Thompson has run 29 Boston Marathons over the past four decades -- he finished 16th in 1976 -- but has also spent a good part of his career as a cardiologist researching the detrimental effects that high-endurance training has on the heart.
Some of his recent research reviews suggest that regular marathon running increases the risks of an abnormal heart beat, damage to heart tissue, and clogged arteries. Other research suggests that those who train hard every day don’t live as long as those who run at a more moderate pace a few days a week.
What’s the optimal amount of exercise you should aim for to lower disease risks and live longer?