Combine cardio with core work to reap the flat-belly benefits of both types of sweat sessions in this Better-Body Challenge. This workout alternates between jumping rope and standing ab exercise, so you can tone your belly while burning serious calories in just 20 minutes. We use one eight-pound dumbbell in this workout to increase the toning potential of each exercise. No weights? No problem. This workout will still be effective without them.
More fitness on:20-Minute Flat-Belly Workout