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Running a marathon can break your butt

Earlier today, Geoffrey Mutai ran the fastest marathon ever recorded -- the Kenyan man finished the race in an incredible 2 hours, 3 minutes and 2 seconds. (Update: Mutai's record-breaker won't be recognized, because today's racers were helped by an unusually strong tailwind.) Including Mutai, about 27,000 runners took over the streets of Boston today, racing in the 115th edition of the oldest annual marathon on the planet -- and after months of hard training, many have surely sustained a running-related injury.

STR / Reuters

Elite men runners start the 115th running of the Boston Marathon in Hopkinton, Mass., today.

In fact, injuries occur in 40 to 50 percent of runners every year, shows a 2010 study published in the journal Current Sports Medicine Reports. You've heard of shin splints, stress fractures and runners' knee -- but the weirdest injury we've heard of has to be "dead butt syndrome."

The silly "dead butt" nickname was made popular this winter when a New York Times blogger dramatically declared, "My butt is dead." Not nearly as hilarious as it sounds, the medical term for "dead butt syndrome" is gluteus medius tendinosis -- basically, one of the muscles that make up your behind becomes inflamed, causing searing hip pain.

The gluteus medius is located on the outer surface of the pelvis, and it powers the thighs forward. Without proper strength training, this muscle is unable to withstand the repetitive stress caused by the long runs that training for a half marathon or anything longer requires.

To beginner marathon runners, all the miles you're expected to log is daunting enough -- and the pros want you to add another exercise on top of that? But it's important to strengthen the lower abdominal muscles and the gluteus muscles -- otherwise, smaller muscles like the gluteus medius muscle end up too weak to bear the brunt of the increasingly ridiculous distances you're running. It's a reminder to runners that when training for a half marathon or longer, just running won't cut it; some kind of cross-training -- whether it's strength-training, swimming, biking, rowing or something else -- is necessary. Keep that butt alive!

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