Diet and exercise.

Pilates work well for toning, but you're going to have to pair that with aerobic exercise and a healthy diet

The upper backside of the thighs respond REALLY well to exercise and tone within 2-3 weeks if you do leg lifts daily or every other day. Also, I find that yoga helps keep me fit all around. Combined with a diet where I don't mix carbs meats ... and only eat fruit 30 minutes before a meal or 2-3 hours afterward, I feel great and notice weight loss in 2-3 weeks.