THE DODGERS' addition of Dr. Chris Winter last year didn't make the same splash as, say, their trade deadline deal for Yu Darvish, but it was at the very least a sign that in this age of analytics in which every team is looking for an edge, the latest frontier of improving sports performance is sleep. Winter is a sleep scientist who is an M.D. at the Charlottesville Neurology and Sleep Medicine Center in Charlottesville, Va., and also consults with the Indians, Padres and Pirates, as well as a half-dozen NFL, NBA and NHL teams. He is one of a growing number of sleep doctors who are lending their expertise to athletes and teams. It's understood that better sleep can lead to fewer injuries, faster recovery and improved performance. The Dodgers and the Pirates in baseball and the Dolphins and the Patriots in the NFL, as well as other teams across all sports have nap rooms, practically unheard of just a few years ago, at their facilities. Consultants, including Winter, are brought in to help athletes adjust their sleep schedules on grueling road trips (some teams bring their own mattresses on the road) and to wind down after games. Says Winter, "Athletes usually practice the opposite—let's go 0 to 60 in 5.8 seconds. But when the game is over, what are you doing to go 60 to 0?"