What could possibly go wrong? A lot: Injuries from the Tough Mudder

"No training on earth can adequately prepare participants for elements such as jumping from a nine-foot height or running through a field of electrical wires while wet and hot," said lead study author Marna Rayl Greenberg, DO MPH, of Lehigh Valley Hospital and Health Network in Allentown, Pa. "The volume and severity of injuries in the Tough Mudder race we studied was unusually high, possibly leading to some permanent disabilities. 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 Tough Mudder is a 10 to 12 mile endurance obstacle course known as "MOB (mud, obstacles, beer) runs." Dr. Greenberg and her team reported in depth on five patients injured at a 2-day event, who were treated (along with 33 other participants not included in the case series) at a local emergency department.

One patient, who had received 13 electrical shocks during the last obstacle in the Tough Mudder, had multiple burn marks from electrical injuries and inflammation of the heart muscle. After being treated in the emergency department, he was admitted to the hospital.

The second patient had sustained multiple electrical shocks to the head while running through water, which resulted in fainting and altered mental status. After being treated in the emergency department, he was admitted to the hospital.

The third patient, after completing 20 out of 22 obstacles, developed seizure-like activity and altered mental status. He was unable to move his entire right side. After treatment in the emergency department, he was admitted to the intensive care unit with Todd's paralysis and discharged from the hospital to a rehabilitation center 4 days later. Six months after the injury, he still had lower right leg disability.

Patient number four sustained face and head injuries after being struck by two electrical cords and landing face first in a hard mound of dirt. He was treated at the emergency department and discharged against medical advice.

A 25-year-old woman who sustained an electrical shock to the chest just before the finish line, after which she was given a beer to drink, was admitted to the hospital for dehydration and rhabdomyolsis, or muscle breakdown.

"In the past few years, obstacle racing has experienced a rate of growth that may be unprecedented in the history of participatory sports," said Dr. Greenberg. "Organizers, participants and local emergency services need to be prepared for a large number of diverse injuries at Tough Mudder and other similar obstacle races."