Marathon Deaths Spark Questions

MELISSA BLOCK, host:

From NPR News, this is ALL THINGS CONSIDERED. I'm Melissa Block in California.

MICHELE NORRIS, host:

And I'm Michele Norris in Washington, D.C.

And now to the world of running. Last weekend's Detroit Free Press/Flagstar Bank Marathon started out uneventfully. About 9,000 runners lined up under clear skies to participate in the 32nd annual race. But by the end of the day, the event was overshadowed by tragedy. In a span of just 16 minutes, three male runners, ages 26, 36 and 65, collapsed and died while running in the 13.1 mile half marathon. The autopsies were inconclusive. A few weeks ago, two other runners died in a San Jose, California half marathon, and a 23-year-old marathoner collapsed and died in Baltimore earlier this month. The recent string of deaths raises questions about the strain that long-distance running puts on the body and the lack of preparation by some runners.

To talk about this, we're joined now by Dr. E. Lee Rice. He's the medical director of the San Diego Rock 'n' Roll Marathon and the Lifewellness Institute. He joins us now from San Diego.

Doctor, welcome to the program.

Dr. E. LEE RICE (Medical Director, San Diego Rock 'n' Roll Marathon; Lifewellness Institute): Thank you.

NORRIS: Statistics suggest that there's been quite an increase in the number of people who are participating in marathons and half marathons. What kinds of questions does that raise about training and preparation and even liability?

Dr. RICE: I think it raises a ton of questions, actually, about all of those things. Statistically, in 1976, there were approximately 25,000 marathon runners. And in 2008, the latest statistics are approximately 425,000. The average running history of the average runner has significantly changed, and with that comes the question of are these people really fit and trained well enough to safely run a marathon.

NORRIS: What kind of strain does a marathon put on the body?

Dr. RICE: It's not unusual for marathon runners, people who run for more than three hours at a time, to have some blood markers that show that there is some inflammation or irritation caused to the heart muscle itself. So it's often not so much what we do as how we do it. And if people are running beyond their capability, which means beyond their level of training and their body's ability to adapt to that level of strenuousness, then there can be muscle breakdown, cellular injury or even death and complications that go along with that.

NORRIS: What kinds of things lead to the deaths of these marathoners? Are we talking about cardiac arrest, too much fluid, too much heat?

Dr. RICE: Cardiac problems break down into younger runners and older runners. In older runners, meaning probably over the age of 50, the greatest cause of death while running is cardiac disease.

For younger runners who die, it usually is some yet undiscovered congenital abnormality in their heart, either hypertrophic cardiomyopathy, which is an enlargement of the heart muscle itself, or some change in the normal placement of the coronary arteries themselves. And those things are not normally detected in a typical examination, and the athletes generally are totally unaware that they even exist.

The other thing that can happen in running is what we call dilutional hyponatremia, basically water intoxication, and that intake of water actually surpasses their body's sweating capability. And then they get their sodium diluted. And that loss of sodium concentration in the cells actually causes a potentially fatal cardiac arrhythmia.

I think the bottom line for most runners is that they are their own very best gauge of what's strenuous for them and what's not. And unless they pay attention to their bodies and they train to allow their bodies to adapt to the running condition before they really go for it and try and do a personal best in a time, then there will potentially be some dangers.

NORRIS: Dr. E. Lee Rice is the medical director of the San Diego Rock 'n' Roll Marathon and the Lifewellness Institute.

Doctor, thank you very much for being with us.

Dr. RICE: Thanks very much for having me.

NORRIS: And if you're thinking of running a marathon, you can find some advice from Dr. Rice on our Web site, that's at npr.org. Transcript provided by NPR, Copyright National Public Radio.