A competitor makes her way through an obstacle during the annual Tough Guy race "the toughest race in the world" at Perton in Staffordshire, England, Sunday Jan. 26, 2014. Tough Guy claims
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Competitors make their way across an obstacle during the annual Tough Guy race "the toughest race in the world" at Perton in Staffordshire, England, Sunday Jan. 26, 2014. Tough Guy claims to
Rokman | The World's Hardest Race According to Science the World's Hardest Race According to ScienceA debate has been running for years. Which foot race is the world's hardest? By utilising scientific
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