Mike McCastle has found a very unusual way to benefit others: by enduring agonizing physical challenges. A Navy veteran with a penchant for philosophy, plus a very high tolerance for suffering, McCastle has taken on a series of tasks inspired by the Greek myth of the Twelve Labors of Hercules to raise funds and awareness for important causes like cancer research and mental health services for military veterans. Since 2013, he has run an ultramarathon while wearing a 40-pound weighted vest, pulled a truck across California’s Mojave Desert, and flipped a tractor tire for 13 miles, among other crazy feats. What makes someone believe that this is the best way to help people in need? And how on earth has survived these epic endeavors?

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