Even though athletes have more plaque, it’s usually hard and chalky, not soft and gooey — so it’s less likely to suddenly break off and cause a heart attack.

Older athletes who train hard for many years tend to have more calcium deposits and fatty buildups in their heart arteries, but these buildups are usually hard and stable, not soft and dangerous.

The plaque buildup in endurance athletes is mostly hard, chalky calcium, while in non-athletes it’s softer and greasier—this might make athlete plaques less likely to suddenly break and cause heart attacks.

Even though endurance athletes have more fatty deposits in the main heart arteries—especially the soft, unstable kind—they don’t have the dangerous features that usually make plaques burst and cause heart attacks.

Even though super-active athletes have more plaque in their heart arteries, the plaque they have is harder and less dangerous-looking than the softer, riskier kind seen in less active people.

Even though elite athletes have more plaque in their hearts, the type of plaque they have is harder and less likely to rupture — which might be why they live longer than you’d expect.