Your problem zone

Bottom-heavy lower body, thick thighs

Your goal To get slimmer thighs, a firmer butt, sleeker hips

The 10-20-30 promise Your lower body is working against constant resistance as you perform these exercises, which boost strength and endurance in your hamstrings, quadriceps, buttocks, upper hips and inner thighs. "By about session 20, you'll notice your rear is higher," Ungaro says. "By the end, your legs will look longer and your silhouette from the waist down will be much shapelier."

Cardio Rx Run or walk on a steep incline (uphill if outside, or on at least a 4 percent incline on a treadmill or elliptical trainer) or work at a high resistance on a stair climber. You can also try activities such as inline skating or cross-country skiing to slim your inner thighs and upper hips.