A little less than a year ago, I wrote on these pages about the long-standing controversy of whether running is good or bad for your heart.
On the one hand, in a 2012 article for the Mayo Clinic Proceedings, cardiologist James O’Keefe and collaborators claimed that “long-term excessive endurance exercise may induce pathologic structural remodeling of the heart and large arteries.” The idea, here, is that excessive running may thicken the heart tissue, causing fibrosis or scarring, and this may lead to atrial fibrillation or irregular heartbeat. Prolonged exercise may also lead to “oxidative stress,” a buildup of free radicals that may bind with cholesterol to create plaque in your arteries. The point, according to O’Keefe, is to get the right dosage of exercise — as in too much of a good thing ends up being bad for you.
A critique of the early studies is that they were small and needed a larger cohort of runners. For example, Paul T. Williams, a biostatistician from Lawrence Berkeley Laboratory, has been following 156,000 men and women since the early 1990s. He insists that more is better. In his huge study, Williams found that men running at least 40 miles a week (a pretty serious mileage) were 26 percent less likely to develop coronary heart disease than those running just 13 miles per week.
Of course, serious runners, people that log at least 30 miles a week (myself included), want to know. As I mentioned in last year’s article, more detailed studies are needed. As Gretchen Reynolds of the The New York Times reported, two new studies are out, and the verdict is that long-term endurance athletes, especially men, do show a high incidence of plaque build-up in their arteries.
However, there are good plaques and bad plaques, and the plaque composition makes all the difference.
One study, published in the journal Circulation, was conducted in the Netherlands with 284 long-term male athletes, aged between 48 and 62. The study used non-contrast and contrast-enhanced…