and though i am, to be modest, in the best shape of my life of late, it's a daunting hike. the climb gradual, then steep. the footing ranging from rocky to spongy, and wet. mile after mile. me trying to look cool, make it seem like this is nothing unusual. but really, i'm dyin'. he's a nascar champion who's she's a world-class swimmer who's stared down the best in her sport. but for both of them, the most challenging opponent was...