About 1.5 million people take part in obstacle races every year. And according to reports, they have more to worry about than bumps, scrapes, and bruises as they crawl through muddy bogs and wade through standing, murky water.
Bloody diarrhea has become a health risk for those who participate in events such as Tough Mudder, Warrior Dash, or Spartan Race, according to a report from the Washington Post.
Last week, the CDC reported that 22 people who took part in a long-distance adventure race held on a cattle ranch in Beatty, Nev. in 2012 suffered from fever, vomiting, and bloody diarrhea following the race.
The race reportedly left them infected with campylobacter coli, a common bacteria that causes a week of diarrhea, cramping, abdominal pain and fever, two to five days after exposure.
Not all those who participate in such events are affected, but for those who are, it can be very dangerous.