According to a Canadian research investigation, running a marathon can temporarily damage the heart which, for those marathoners who lack proper aerobic training, can cause a heart attack during a race or shortly after crossing the finish line.
Cardiologist and professor of medicine at Laval University in Quebec, Eric Larose, began the study in 2008 with 20 runners, ages 21 to 55. The individuals ranged in fitness levels, from a first-time marathoner to a 35-year marathon veteran.
Heart function was tested six to eight weeks before the marathon, immediately after the race, and then again three months later to evaluate how their hearts were affected. The findings suggest that those runners without proper aerobic training are more at risk for heart damage.
Through MRI, VO2 Max testing and bloodwork, Larose and his associates found that changes in the left ventricle of the heart – the heart’s main pumping chamber – occurred directly after the race. The left ventricle is divided into 17 segments and 53% of those segments experienced decreased functionality, most likely due to inflammation due to exertion.
Larose stresses that the damage is not permanent. At their three month checkups, the runners’ hearts were back to normal function. “We aren’t suggesting marathons are dangerous or that people shouldn’t run,” Larose says. Most importantly, the findings from this study support the importance of proper training. The more fit and trained a runner is, the less effect the strain of the marathon has on the heart.
Larose’s findings were presented earlier this week at the Canadian Cardiovascular Congress.
SOURCES: Eric Larose, M.D., assistant professor of medicine, University of Laval and research-scholar, Quebec Foundation for Health Research, Quebec City, Canada; Ori Ben-Yehuda, MD, director of the coronary care unit, University of California San Diego; presentation, Oct. 25, 2010, Canadian Cardiovascular Congress 2010.
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These are the types of studies that are always misleading. They begin with parameters for fitness that are not even scientific like ” first marathoner vs 35 years marathoning veterans” this suggests the 35 years marathoner are most fit! That’s crap. Who is more fit first time runner with a 2.30 hr marathon time or a 35 years marathoning veteran that has loged most in 5 hours?
Then there is this training regiment. 75% Effort for one runner could be 100% for the other. So is the damage necessarily due to mileage(26.2) or simply a manifestation that probably can be seen after a 10 mile bout.
This was a poorly designed study.
Damages were identified through testing directly after the marathon, changes were found in the left ventricle. I linked to this article which further explains the findings.
The article doesn’t mention at what point the heart is damaged. It also states the “damage” is temporary which seems to be the same that weightlifters experience in their arms. It just proves runners have bigger hearts 🙂