Want a toned middle in no time? We've designed a challenge with celebrity trainer David Kirsch that will whip you into shape in just three weeks. Read on below to get started!"The key is a combination of proper nutrition plus cardio and weight-bearing exercises done at a high intensity," says Kirsch. We've broken down the workouts and eating plan so you'll have all the insider tricks Kirsch's clients like Heidi Klum have. Get started today!
Always check with your doctor before starting a new diet or workout plan.Read MoreLess