MINNEAPOLIS (WCCO) — The Cook County Sheriff’s Office says a three-time Superior Trail Race finisher died of cardiac arrest while running the race in May.

Jon Mathson, 41, of Eagan collapsed and died while running the 25KM race on Saturday, May 20.

The Midwest Medical Examiner’s Office confirmed his cause of death, saying he died from natural cardiac arrest during exertion due to antherosclerotic coronary artery disease.

Mathson had no known medical history.