Body of Work: The Top 20 Fitness Icons

The Comeback Kid: Dara Torres

Ronald Reagan was in office when 17-year-old Dara Torres swam in her first Olympics, in Los Angeles in 1984. Four presidents later the California native is still making waves. Now 45, an age when most swimmers have long hung up their Speedos, Torres is trying for a mind-boggling sixth Olympics this year in London. She's already swum the qualifying time in the 50-meter freestyle, the event for which she holds the U.S. record. The oldest woman ever to swim in the Olympic Games, she's attempting to add to her total medal count of 12, including three silvers from the 2008 Beijing games, where she narrowly lost the gold in the 50-meter freestyle to a German swimmer half her age.

Unlike many women on the other side of 40, Torres is happy to reveal her age. Her statuesque physique, with its broad shoulders and egg-carton abs, seems chiseled from marble -- if marble had a tan. "I found myself saying 'Age is just a number' so many times that I titled my memoir with that mantra," says Torres, who lives in Florida with her 6-year-old daughter, Tessa Grace, and trains up to six hours a day. "Age is definitely part of who I am, but it certainly doesn't define me."