Many former couch potatoes believe that a distance run is out of their league--and not just the marathon. But Jeff Galloway, the popular runner and running coach, is a proponent of the "run walk" method, a training plan that has inspired millions of would-be runners to give the sport a try, even as "purists" scoffed. This method incorporates walking breaks for every runner--from those who are making their first slog around the block to full marathon maniacs. In this article from The New York...