For some men, easing up on exercise might provide some benefits. A recent study found that white men who exercise intensely are 86 percent more likely to get plaque buildup in the heart arteries by middle age than those who exercise less.

To study the exercise habits of more than 3,000 black and white men and the condition of their arteries, researchers at the University of Illinois at Chicago separated them into three groups — those who exercised for less than or more than the recommended 150 minutes a week and those who went way beyond that, exercising around 450 minutes each week. The study group included men from four U.S. cities whose activity and health data were tracked from 1985 to 2011.

The researchers expected to find the most active men would have the lowest levels of calcium and plaque in their arteries. Instead, they found those who worked out the most were 27 percent more likely to develop coronary artery calcification by middle age than those who exercised the least. They also determined that white men who exercised intensely were 86 percent more likely to have coronary artery calcification than those who worked out less than 150 minutes a week.

The results appeared to have a racial component: Black participants who exercised frequently had no added risk of coronary artery calcification. The findings were published in the Mayo Clinic Proceedings.

The study drew no firm conclusions about a cause, but researchers theorize that high levels of exercise over time may put stress on the arteries. Researchers said the findings do not suggest that anyone should stop exercising.

But when it comes to your heart arteries, a little less time working out may not be a bad thing.