Heart Damage and Marathon Running

As a doc who underwent major open heart surgery in 2006, and is now trying to lose weight and get healthy by training to run the 2011 Los Angeles Marathon, and do Triathlons .. this article was very interesting to me!

For those that are not familiar with my cardiac escapades, you can peruse more here:  About Me (& my heart)

Marathon runners suffer temporary heart damage

Decrease in blood flow impairs function, may explain sudden deaths, study finds

In brief, Canadian researchers looked at twenty runners (70% were men), and ran a battery of tests before, immediately after, and several months after, the Quebec Marathon (that's 42.195 Km for us metrically-challenged Yanks). Testing included VO2max and cardiac MRI. They found temporary changes immediately after the race, including edema and inflammation. From this, they suggest possible cardiac damage, possibly from transient decreases in blood flow to the cardiac muscle itself. This was felt to be most evident in the less-fit runners, and also exacerbated by dehydration. All seems to make sense to me. None of these 20 runners died or had any events during the marathon. And, all the cardiac changes resolved and reverted back to normal baseline several months after surgery. The study speculates that this temporary heart damage might explain sudden deaths during marathons, or like the recent death of Fran Crippen during a 10K open water swim competition. While Mr. Crippen was clearly fit and in peak cardiac condition, it sounds like the conditions of the race were arduous, hot, and he was indeed dehydrated.

Here are a few quotes from the article, followed by my quick thoughts.

"We know that regular exercise reduces cardiovascular risk by a factor of two or three in the long run, but while we're doing vigorous exercise such as marathon running, our cardiac risk increases by seven,"

Yes, I can believe that. But, I think it is actually a seven fold transient increase in risk, during exercise. (like the death of swimmer, Fran Crippen) On the other hand, the profound 2-3 fold decrease in cardiovascular risk is permanent, every day for the remainder of your life.

"One 2007 study, published in the British Medical Journal, looked at 30 years of marathon data and put the risk of dying at 0.8 per 100,000 runners. According to the researchers on that study, running a marathon is half as risky as driving the same route on a normal day."

Driving the same route in Los Angeles, the risks of dying might be about equal.


My take home message from this article is that I am aware of the risk. As I've mentioned in my "About Me (& my heart)" page, I know that there is a very small chance that something bad might happen during the few hours that I am running, biking, swimming, or racing. But, I am fairly certain that something equally bad (or worse) will happen someday, while sitting on the couch, being fat and sluggish. I'll go with the lifetime 2-3-fold decrease in my cardiovascular risk, looking better, feeling great, being energetic, playing with my kids, etc.

In the meantime, I always keep a mindful eye on training smartly, safely and being prudent. I will also look into the VO2max parameter, as I am unfamiliar with that. And, be a little more cognizant of avoiding dehydration. When I run, I'm liberal with my walking breaks. Primarily, I am interested in finishing the distance, not hitting a blistering pace or PR.

I know what's at stake, and I don't plan on going anywhere soon. What do you think about this article?