five years, while 14 were first-time ultramarathoners who’d previously run at least one regular marathon.
After the event, the experienced runners were more likely than the first-timers to have elevated levels of blood biomarkers that measure heart health, but those levels did not pose a risk of heart damage. The experienced runners did have higher levels of cortisol.
The higher levels in the experienced runners reflected the greater load on the heart, according to the authors of the study published recently in the journal Heliyon.
“Experienced runners performed with greater intensity and speed, which placed strains on their hearts. Novice runners ran with less intensity, which resulted in lower cardiac biomarker levels,” Hohl explained in a journal news release.
He noted that ultramarathon runners self-pace for a set time and towards an established endpoint. Runners with different levels of training experience and