Do what you like. If you hate to run, then planning to run at 6 a.m. is going to make it incredibly difficult to roll out of bed at 5:50. "Doing something you enjoy is going to help you stay with it," she says. "What do you prefer doing? Is it a class you take? Or is it running, lifting weights, or just walking?"
Transport yourself to work. Try combining your workout with your commute. "Some people that I know are really dedicated to riding their bikes to work, and that's a good way that you'll guarantee you'll get your workout in—in the morning and in the afternoon," Valentour says. Only caveat: If your office doesn't have showers, you may look pretty sweaty for the early part of the day.
Teach a class. This works for Valentour, who admits that she is not a morning person. "I teach yoga in the mornings now," she says. "I wouldn't exercise in the mornings, but I get paid for it, so I have to now."