Jillian Michaels' Calorie-Burning Workout

Credit: Jim Wright

Shed pounds fast

Short on time? No problem. This circuit, created for Health by Jillian Michaels, combines strength-training and cardio so you torch major calories while you tone.

"You want to do what is going to be the most effective for your calorie burn and your schedule," she explains. Do each move as many times as you can in 30 seconds, while maintaining good form, then go to the next one. Complete circuit three times, twice a week.

Jillian's key rule: "Don't rest! You shouldn't do a move and then wait to do another one. Go from one move to the next to the next. So while one group of muscles is resting, you've moved on to a different muscle group. If you've done push-ups, do lunges; if you've done lunges, do pull-downs. Keep it moving!"

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