People who train hard and regularly for endurance sports are less likely to have dangerous, unstable plaque in their heart arteries that could suddenly cause a heart attack.

Even though endurance athletes have more plaque in their heart arteries, the dangerous, rupture-prone kind is actually rarer in them than in healthy non-athletes, which might explain why they rarely have heart attacks.

People who regularly do long, intense workouts like running or cycling tend to have less dangerous types of plaque buildup in their heart arteries than people who don't exercise much.

Even though athletes are super fit, their heart plaques aren’t more stable or ‘safer’ than those of healthy non-athletes—so being an elite athlete doesn’t make plaque less dangerous.

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.

Men who have trained for decades as elite endurance athletes, like cyclists or marathoners, tend to have more fatty deposits in their heart arteries than healthy men who exercise moderately—even when both groups are fit and have normal cholesterol and blood pressure.