Running Marathons Isn’t Bad for the Heart

Several past research studies have warned that high levels of endurance exercise—like running multiple marathons—could be a risk factor for future heart problems. According to a study from the Technical University of Munich in Germany, there’s no need to give up those marathons just yet.

The primary purpose of the study was to address previous findings linking marathon participation with atherosclerosis. The researchers theorized that those findings could have been due to other risk factors, like smoking history or small sample sizes. This study recruited 97 healthy male marathoners aged 44 ± 10 years who had no risk factors for atherosclerosis.

The runners provided a detailed training history and underwent tests to determine peak oxygen uptake, arterial thickness, blood pressure, endothelial function and more.

At the time of the study, the men had completed a median of eight half marathons, six full marathons and three ultramarathons. They’d logged an average of 36 training miles per week and more than 1,000 training miles per year.

“In this cohort of healthy middle-aged male runners, no significant impact of exercise capacity, training history, number of previously completed half-, full or ultramarathon races or marathon finishing time on markers of subclinical vascular impairment was observed,” the authors said.

Age seemed to be the only risk factor; researchers discovered abnormalities among the older runners.

The authors concluded that “repeated marathon running per se does not pose an independent risk factor for the development of premature vascular dysfunction subsequently leading to atherosclerosis. Instead, running multiple marathons appears safe from a vascular perspective in having a neutral effect on subclinical markers of vascular impairment.”

This study was published in the European Journal of Cardiology (2017; doi: https://doi.org/10.1177/2047487317713326).