Workout details: Do a quick dynamic warm-up (1-2 minutes of jumping rope, jacks, or high-knee marches), and then do 1 set of the prescribed number of reps (or time) for each exercise. Move quickly from one move to the next with little rest in between. After you've finished the last exercise, rest 1-2 minutes, and then repeat the entire circuit 1 more time for a 15-minute, fat-blasting workout. If you're up for a challenge, complete 4 circuits total for a full 30-minute session.

You’ll need: A kettlebell (5-15 lbs, depending on your level)

(Never worked with a kettlebell before? Read these helpful tips before getting started.)

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