I sometimes wonder about those serious little gymnasts on TV who perform unfalteringly for millions and then retire at age 18. What happens next? . I bet that for as long as they live, they find comfort in the uneven bars. I bet, even if their careers were full of pain, that they explain the world back to themselves using the lessons they learned with chalk on their hands. . My story is much less extreme than the little Russian gymnasts’. But from age 14 until I retired from elite competition at age 30, running dictated my life: I ran twice a day, 100 miles a week. I followed coaches across the country and lived out of suitcases for months a year. I always knew my national ranking, and I knew I’d be fired if it fell too low. . I’ve been booed. I’ve received hate mail. I’ve had the worst moments of my life replayed in slo-mo on national TV. I’ve been screamed at by coaches, told I was broken. I heard my bone crack through mid-race. I've pulled out my own toenails. . I’ve also been cheered on by 20,000 screaming fans. I’ve been paid to do nothing but run. I’ve received letters from fans I’ve reread a hundred times and can still send my heart into my throat. . Now, two years removed from my career, there are things I understand more and things I understand less about what running was to me then, and what it is to me now. This is what I’m sure of: The goofy exhaustion at the back of the bus is what best friends feel like. I need mentors who are direct and honest, even when it hurts us both. I’ve got no patience for time wasting, patronizing or excuses. I believe if I haven’t worked, hurt, cried and bled for something I don’t really deserve it. I believe in the power of one human’s will to prove every social, physical and fiscal predictor wrong. I believe that I am not a winner, but rather a fighter. I believe that is something to be embraced. . People ask if I carry scars from those years. The answer is yes. I can see the scars of a hundred thousand miles on these legs. I can feel them in the craggy calcium deposits on my now-healed bones. But scarred tissue is tough. I am scarred, and so I am fortified.