Remember Bob Kennedy, the last American-born middle-distance medal contender? We forgive you. After all, U.S. running has suffered through two decades that we'd kindly call subpar. But all of a sudden the sport is back. Running-shoe sales have jumped 35 percent since 2001, and the phrases "American distance runner" and "Olympic medal contender" are no longer mutually exclusive. Just ask Ryan Hall, who recently ran the fastest marathon in U.S. Olympic-trial history. "The world is taking notice," says Hall. As should you. For a start, try on a half-marathon training program tailor-made for you by Hall's coach.