"100 kilometers? That is further than I drive!" This is usually the most common response when people find out that I run ultramarathons. And honestly, I completely get it. Running for 31, 62, or 100 miles certainly seems like it is a little bit crazy. Why do runners subject themselves to the pain and discomfort of running such incredible distances? We even pay to run these events. As my brother-in-law told me, he'd be happy just to drop me off 100 miles from my house, as long as I paid him $100 first. So why do we do it? Why do we spend months training just so we can go…