Cardio Kick Box is a high-energy aerobic workout designed to keep you moving and boost your fat-burning capabilities while at the same time giving your muscles a day off from wither-training. Jillian recommends doing Cardio Kick Box once a week, in the middle of the week, to break up your regular exercise program. this program is to get out there and have some fun, and keep your body moving.

Jillian Michaels, the trainer from NBC's The Biggest Loser and self-proclaimed "TV's toughest fitness guru," runs through circuit training like a drill sergeant on caffeine. Her theory is to keep moving in between exercises to burn twice as many calories, so she cycles her team through sumo squats, mountain climbers, jump ropes, shoulder raises and bicycle moves without taking a breath. If she doesn't think one of her comrades is picking up his knees high enough, she makes everyone do 30 more, with a sadistic grin. As a result, you can almost literally watch the muscle burn. Michaels' Shape-Up Front DVD works out the chest, shoulders, triceps and quads. It also requires two props: a bench-style exercise step and light dumbbells. The DVD features include printable diet/exercise logs, nutrition tips and recipes. Despite a lower-level option, it isn't for anyone looking for a low-impact aerobic workout. --Ellen A. Kim