Athletes with early signs of heart artery plaque experience much higher blood pressure when pushing hard during a long bike race than athletes without plaque, meaning their hearts and blood vessels are under more strain.

Athletes with early heart artery plaque put more strain on their hearts during intense exercise, as shown by a higher number that combines heart rate and blood pressure—meaning their hearts are working harder than those without plaque.

The bigger the rise in the bottom number of blood pressure (diastolic) during a hard race, the more likely an athlete is to have early heart artery plaque—even if their resting blood pressure is normal.

When athletes with early heart artery plaque stop a hard race, their heart rate doesn’t adjust as smoothly as those without plaque, suggesting their body’s automatic control system for heart rate and blood pressure isn’t working as well.

For older male athletes who work out really hard—like sprinting or intense cycling—doing more of this super intense exercise over time seems to be linked to more calcium building up in their heart arteries, which could be a sign of plaque growth.

For older male athletes, doing a lot of hard but not extreme exercise—like fast running or cycling—seems to be linked to less calcium buildup in heart arteries over time, compared to doing super intense workouts.