Like Chris, Martina has maintained her killer physique. "The thing about being in Colorado, and particularly in this valley, is that it's easy to be healthy," she says. "Easy to eat well, easy to do exercises inside, outside. It's just heaven on earth, I think."
Martina says she doesn't need expensive equipment to stay in shape—just two dog leashes and the great outdoors.
Watch Martina's workout.
Although she's happy with her life now, Martina doesn't regret her past. "I'm thankful for my past because it's brought me to this point and, most of all, thankful to tennis because it gave me a great life."