After years of continuous, pro-exercise fanfare, could it possibly be true that intense exercise causes more harm than good to your cardiovascular system? The collective results of several studies on athletes and coronary artery disease seem to indicate that vigorous exercise can in fact lead to arterial plaque buildup and calcification.

But don’t rejoice just yet, couch potatoes. The correlation between exercise and arterial plaque buildup is actually quite complex, and even somewhat mystifying to researchers.
A 2008 study conducted by German researchers indicated that marathon runners who participated in the study had significantly higher coronary arterial calcium levels than other, less active participants. High levels of coronary arterial calcium levels correlate directly with hardened plaque buildup in one’s arteries.

Since the 2008 German study, more data has emerged from other similar studies, and the results have been just as puzzling – sustained, vigorous exercise increases one’s risk of developing coronary artery calcification. But here’s the most interesting part of the studies’ collective results; the type of plaque that forms in an athlete’s arteries tends to be healthier and less likely to causes serious health issues, like a heart attack or stroke.

While more studies are needed before we can say, without a shadow of a doubt, that running multiple marathons for years-on-end causes arterial calcification and hardened arterial plaque buildup, the link between arterial health and vigorous exercise is still a valid concern. For many, however, the true question is not about how much plaque buildup is in an athlete’s arteries, but how much is in the arteries of a sedentary person. After all, the studies done on athletes and plaque buildup seem to indicate that continuous, long-term exercise is associated with a much less dangerous type of arterial plaque.

So what can we take from the results of these studies? Perhaps the rule “everything in moderation” isn’t as terrible as it may seem for both diehard exercisers and sedentary sloths alike. If one does a little less, and one does a little more, they just might meet somewhere in the middle of unquestionable cardiovascular and arterial health.