He lost his left leg, just below the knee, in a farming accident, when he was eight years old. For many years after, the disability slowed him down. Then one day he was invited to play wheelchair basketball. He loved it, thrived in it and eventually became the best U.S, player in history. That led to triathlons. Which led to mountain climbing. Which led to Jeff Glassbrunner becoming the first American amputee to scale Mount Everest. ​And he's not done conquering!