WINCHESTER, ENGLAND - OCTOBER 25:  A competitor falls in the mud near the finish of the Tough Mudder London South on October 25, 2014 in Winchester, England. The world-famous Tough Mudder is military style endurance event over 10-12 mile obstacle course designed to test all-around strength, stamina, teamwork, and mental grit.  (Photo by Justin Setterfield/Getty Images)