Several reports have emerged over the past few years linking endurance exercise with heart problems. In a report published in the 2011 European Heart Journal, researchers studied 40 trained athletes with no known heart problems who were to participate in one of four events: an endurance triathlon, alpine cycling, an ultra triathlon or marathon. The researchers obtained magnetic resonance imaging (MRI) from each athlete 2-3 weeks before the race, 1 hour post-race and 6-11 days post-race. When examining the results, the researchers noted that 1 hour after the race, the athletes’ right ventricles had changed shape, volume had increased and function had decreased. Fortunately, in most of the subjects, heart shape and function returned to pre-race condition after a week. However, the five athletes with the most experience in endurance racing showed more permanent scarring.
Researchers noted that intense endurance exercise causes acute dysfunction of the right ventricle, but not the left ventricle. Although short-term recovery appears complete, chronic structural changes and reduced right ventricle function are evident in some of the most practiced athletes. The long-term clinical significance warrants further study.
The authors pointed out that the results of this study do not necessarily indicate that participation in endurance activities is unhealthy.