A veteran of eight marathons with a competitive streak a mile long, Sarah Bowen Shea is a freelance writer specializing in fitness, health, gear, and parenting. She contributes to a variety of publications, including "Shape, SELF, Runner's World, Whole Living," and the "New York Times." She lives in Portland, Oregon, with her husband, Jack, and three young children, including boy-girl twins. Online: anothermotherrunner.com A dedicated if not natural runner, Dimity McDowell writes regularly about sports and fitness for a range of magazines, including "Runner's World" and "ESPN: The Magazine." She lives and runs (at 5,280 feet) in Denver, Colorado, with her husband, Grant, two kids, and two dogs. Online: anothermotherrunner.com