Believe it or not, the best way to trim your waist is to burn calories with things like running, walking and cycling. This is because you can't "zap" fat off your middle with target-toning exercises like crunches. Crunches will strengthen and firm the area, but if you have excess fat layering around your middle, they won't help much with that. Losing weight overall will help you lose from your middle. So you need to aim to burn more calories and/or take in fewer calories.

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Do it three times a week, while cutting calories, and you should see results within six weeks.
The Warm-Up
Raise your heart rate with any one of the following two-minute cardio bursts. If you ache from an activity, discontinue it and opt for another.

Cardio Choice 1: Jumping Jacks
Perform them continuously for two minutes, on a carpet or an exercise mat. If necessary, take a short break after every 10.

Cardio Choice 2: Jumping Rope
Jump on a carpet or mat, wearing sneakers with strong support.

Cardio Choice 3: Stair Climbing
Do a full flight or just one step (switching lead leg every 30 seconds).