Ultra-endurance events can be bad for your heart. Or maybe not.
That undefinitive statement comes courtesy of contradictory studies both reported Aug. 31 on the Science Daily site. We’ll start with the up(heart)beat report.
The Karolinska Institutet and the Swedish School of Sport and Health Sciences studied 15 athletes (12 males, three females) at the Adventure Racing World Championships. The event covered 800 kilometers in the disciplines of mountain biking, trekking, kayaking and in-line skating and took about six days, with competitors essentially going nonstop for 150 hours at an average work intensity, measured in terms of VO2 peak, of 40 percent. Before and after the event, the athletes were assessed to see how their hearts responded. While some of the athletes registered increased levels of certain blood markers, suggestive of cardiac damage, immediately after the race, those markers were back to normal within 24 hours. Researchers believe the spike wasn’t the result of cardiac damage, but rather the body’s way of protecting and regulating growth. Further, the athletes who finished strongest and did the best had the least affected hearts.