How Dangerous Are Tough Mudders?

With names like Electroshock Therapy, Everest, Fire Walker and Trench Warfare, it's not exactly a secret that Tough Mudder obstacles are designed to rough you up. How could a race billed as "probably the toughest event on the planet" not be challenging?

But after a 28-year-old participant died during an April 2013 Tough Mudder, witnesses and critics questioned the organization's commitment to safety.

Now, a new study aims to point out just how many injuries are occurring at these races -- and how unique the injuries are. "The volume and severity of injuries in the Tough Mudder race we studied was unusually high, possibly leading to some permanent disabilities," lead study author Marna Rayl Greenberg, DO MPH, said in a statement. "The 1.5 million people who are predicted to enter obstacle races like this in the next year should be well aware of the risks they are taking."

The study, published in Annals of Emergency Medicine, describes five patients injured at a two-day event who were treated at a local emergency department in Pennsylvania. There were 33 others who were injured and treated at the same hospital but were not included in the study.

One of the patients had burn marks and heart inflammation after receiving 13 electrical shocks. Another had fainted after multiple electrical shocks to the head. A third was unable to move his right side after seizure-like activity and was still experiencing problems with his right leg six months later. The fourth patient had face and head injuries from being struck by electrical cords, and the fifth was admitted to the hospital with rhabdomyolsis (in headlines these days for its association with CrossFit) and dehydration.

In West Virginia, a local hospital had to turn patients away after the injured participants from a Tough Mudder in the area overloaded its resources, CBS Baltimore reported.

Unlike with marathons, where the training enhances race-day performance and preparedness, obstacle races are nearly impossible to train for, the study authors write. There's little one can do to "prevent injury in an event in which obstacles include having to jump off a 9-foot height or run through a field of electrical wires (while the participant is wet and hot)," they write. "Training might not have prevented many of the injuries that occurred in this event."

CORRECTION: A previous version of this article incorrectly stated the location of the hospital that had to turn injured patients away due to overloading of resources from a Tough Mudder event. The correct location of the hospital is West Virginia.