Older male athletes who have high heart disease risk and train a lot are much more likely to have serious plaque buildup in their heart arteries than those who train just as much but have lower heart risk.

For older male athletes who are otherwise low-risk for heart disease, doing a lot of exercise may help reduce plaque buildup in their heart arteries.

Men who have trained for decades in marathons and endurance sports are more likely to have calcium deposits in their heart arteries than men who don't exercise much—even if they're otherwise healthy and have no heart disease risk factors.

Doing very hard exercise — like sprinting or intense cycling — is linked to more calcium buildup and plaque in the heart arteries, even if the total amount of exercise is the same as someone who exercises less intensely.

Men who have exercised very intensely and for many years are more likely to have calcium deposits and plaque in their heart arteries than those who exercised less, even though they tend to live longer.

Just doing short, intense workouts isn’t linked to more heart plaque—what matters more is how many total hours you spend training over time.