Competitors warm up backstage during the Arnold Classic Europe bodybuilding event in Madrid, Spain, September 25, 2015. (Photo by Susana Vera/Reuters)

A competitor shouts as he takes part in the “Tough Guy” adventure race near Wolverhampton, central England, on January 29, 2017. The Tough Guy event, which is being held for the final time in its 30th year, challenges thousands of competitors to run a gruelling course whilst negotiating over 200 obstacles including: water, fire, and tunnels. (Photo by Oli Scarff/AFP Photo)

Competitors in the Pro Bikini division pose during the Arnold Classic Australia at The Melbourne Convention and Exhibition Centre on March 14, 2015 in Melbourne, Australia. (Photo by Robert Cianflone/Getty Images)

A competitor scrambles in the mud under barbed wire during the Tough Guy Challenge 2009 at South Perton Farm on February 1, 2009 in Wolverhampton, England. The biannual event to raise cash for charity challenges thousands of international competitors to run through a gruelling set of 21 obstacles including water, fire and tunnels after a lengthy run at the start. (Photo by Christopher Furlong/Getty Images)

Competitors take part in the Red Bull Crashed Ice Cross Downhill World Championship in Marseille, France, January 14, 2017. (Photo by Jean-Paul Pelissier/Reuters)

A competitor solves a Rubik's cube using his feet as he prepares for the Rubik's Cube European Championship in Prague, Czech Republic, July 15, 2016. (Photo by David W. Cerny/Reuters)

A competitor jumps from the Old Bridge during Red Bull Cliff Diving Competition in Mostar, Bosnia and Herzegovina on August 15, 2015. (Photo by Dado Ruvic/Reuters)

People watch a competitor riding a homemade vehicle without an engine on a 300-metre-track during the Red Bull Soapbox Race in Amman, Jordan September 4, 2015. (Photo by Muhammad Hamed/Reuters)