Are there negative health consequences to running ultramarathons?
Q. Are there negative health consequences to running ultramarathons?
A. In recent years, more and more people have been pushing the envelope of distance running, competing in so-called ultramarathons (races with a distance longer than the traditional marathon’s 26.2 miles). Some races take place over multiple days and add into the equation inhospitable terrain such as high altitude, steep climbs, and routes through deserts. Many of us may question the sanity of such races, but they also raise a question about the runners’ physical health: How long is too long?
Science does not yet have an answer to whether running extreme distances takes a greater toll on the body. Although there’s a large body of literature on marathon runners, there are relatively few studies on people running longer races. One of the most comprehensive, published this year, tracked medical problems in nearly 400 runners participating in a multiday desert ultramarathon race. Although nearly 85 percent of them required medical care at some point, over 95 percent of the injuries were minor, such as blisters, swelling, tendonitis, or dehydration. “The majority of people who do this activity finish without any significant type of injury,’’ says Brian Krabak, lead author of the study and a sports medicine physician at the University of Washington. Keep in mind that people who compete in these races are generally in excellent shape to begin with.
This study examined only short-term injuries; Krabak says it’s more difficult to determine how injuries may accumulate over years of running extremely long distances. A 2007 review of studies on running injuries found a higher risk of injury in men who ran more than 40 miles per week, but paradoxically it also found evidence that increasing weekly distance was protective against knee injuries. It may be that training determines the exact relationship between distance and injury.
Krabak says that in addition to getting in shape and gradually working up to longer distances, it’s important for ultramarathon runners to “understand the race you’re entering.’’ Environmental factors become important; some races involve extreme humidity, temperature, or altitude, and pass through wilderness where medical assistance can be scarce. Simple precautions such as blister prevention, good nutrition, and appropriate clothing are critical.