Should You Worry About Cardiac Arrest While Running a Half Marathon or Marathon?

Over the course of a month in spring 2014, at least six runners—a 20-year-old in Boulder, a 23-year old in Pittsburgh, a 38-year-old in Maryland, a pair of 30-somethings in Raleigh, a 31-year-old in Brooklyn—have died of cardiac arrest in half marathons around the country. While this stat is staggering, is it indicative of an increasing and terrifying trend among runners? We asked Dr. Kevin Campbell, a cardiologist in Raleigh, North Carolina, who specializes in heart rhythm disorders, to weigh in.

Cardiac Arrest: On the Rise?

Are cardiac arrest events becoming more common among runners? While the latest deaths are certainly unsettling, a study in the New England Journal of Medicine shows that marathons and half marathons are associated with a low overall risk of cardiac arrest and sudden death. In fact, among the 19.9 million marathon and half marathon participants in the U.S. from 2000 through 2010, 59 people suffered from cardiac arrest. That equates to about one event for every 184,000 runners.

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However, when coupled with the increase of runners joining these races—the number of half marathon finishers in the U.S. quadrupled from 2000 to 2013, according to Running USA, the incident rate is on the rise, particularly among men.

"I think that we are seeing more events for two reasons," says Campbell. "Simply because more people are participating in running events and more people are taking on events that they may not be prepared for."

Campbell continues that because events like half marathons are becoming more mainstream, the feat is no longer reserved for highly trained athletes.

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"There are some people who are not up to the task and are at risk," he says. "It may also be a matter of undetected heart disease, the stress of the distance, and the stress of the heat, weather conditions, terrain and distance taken all together."

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