"Tightening up your torso and that ring around your waist, back and upper butt requires lots of cardio and a stepped-up ab/core routine," says Kirsch, who has worked with Liv Tyler, Anne Hathaway, and Faith Hill. See below for your weekly plan.THE PLAN 45 minutes of cardio/light-weights four to five times per week. If you're bored with running or using the elliptical trainer, mix in jumping rope, swimming, or rowing. You can also try one of Kirsch's workouts on his Ultimate New York Body Plan DVD.
Ab/core routine three times per week. "Perform the exercises nice and slow, and really focus on contracting each muscle," says Kirsch.Read MoreLess