A health researcher, practicing physician and endurance athlete weighs in

By Scott Douglas

Over the past few months, a large and sometimes confusing amount of information has come out on whether "excessive" exercise can cause heart damage. Michael Joyner, M.D., has helpfully compiled on one page the claims and the facts.

Joyner comes to the topic from every possible angle – as a health researcher, practicing physician and endurance athlete (including a 2:25 marathon PB). His overall conclusion:

Is there a cardiac risk associated with being super fit and training a whole lot? To the extent there is comprehensive and well controlled data the answer appears to be no. It does appear that in terms of health there are diminishing returns and that people who train “a whole lot” (say more than an hour almost every day) are not better off than people who just do “a lot” (30-60 minutes most days). However, people who do a whole lot of training are probably doing it for reasons other than health that include things like a need to compete, a need for time alone, or the need for some sort of big challenge in life. Not exercising enough is extremely common and dangerous. By contrast, a life time of exercising “too much” is extremely rare and the evidence to suggest it does long term harm to the heart is pretty speculative.

Joyner's one-stop-shopping writing on the topic has a lot more detail on specific areas of concern, and is well worth reading and bookmarking.

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