• Grab an adult-sized hula hoop. Simply keep it going around your waist. To start, stand with one foot in front of the other and shift your weight back and forth (versus around in a circle). And don't worry if you're bad at first; you'll still burn calories, plus get better every time you spin.
  • Dancing may not be the best calorie-burner in the bunch, but it's still a great metabolism booster. The key is to keep the tempo high, choosing songs with fast rhythms like Latin or Bollywood, and don't rest between songs.
  • Jump rope, use a rope with handles that reach to just under your armpits when you stand on the middle of it. Jump with your feet slightly apart and body upright, and keep your jumps low to the ground.
  • You can burn fat by playing tennis even without a partner. Find a flat area near a wall that you can hit the ball against, and stand 10 to 25 feet away, to force you to hit harder. Alternate forehand and backhand shots—then see how many you can do in a row without goofing. Even practicing your serve will get your body in burn mode, because you’ll have to run and bend to pick up your missed balls.
  • Walking briskly can help you burn calories too. Take short, quick steps, keep your torso upright, and pump your arms back and forth (not side to side) in time with your stride. With each step, land on your heel and roll through to your toes.