4 Weeks To Fit And Fabulous

10 Ways to Crush Even More Calories

So pull out your shorts and swimsuit for inspiration and get started—you could be shopping for smaller sizes by the end of the month!

Turn Up Your Fat Burn Plan

You'll do each of the high-powered workouts 2 days a week.

Sample Weekly Schedule

You can move the workouts to different days, but don't do both workouts on the same day, and don't do the same routine on back-to-back days.

Day 1 Cardio Intervals

Day 2 Rest

Day 3 Strength Circuit

Day 4 Rest

Day 5 Cardio Intervals

Day 6 Rest

Day 7 Strength Circuit

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FAT-BURNING CARDIO INTERVALS

2 Days a Week

Fat is one of two key sources of fuel your body relies on for energy; the other is glucose (stored carbs). Most of us burn about equal amounts of each when we're sleeping or sitting around. But the fitter you are, the more fat you burn at rest—up to 70%.

You can rev your fat-burning power by raising your ventilatory threshold 1 (VT1), the point at which you're exercising hard enough that your body shifts from using primarily fat for energy to using primarily glucose. To do this, you need to work out just past this point—a bit out of your comfort zone but not so hard that you're gasping for air (that's closer to your VT2, when you're burning almost all glucose).

How it Works Warm up for 3 minutes at an easy pace (you can carry on a conversation). Next, pick up the intensity for a hard VT1 interval (you should be breathing hard but able to speak in short sentences). Recover at a moderate intensity (you should be breathing normally and able to speak in full sentences). Repeat hard/recovery intervals 3 times, as shown below.

Week 1 3 minutes hard/4 minutes recovery

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Week 2 4 minutes hard/4 minutes recovery

Week 3 5 minutes hard/4 minutes recovery

Week 4 5 minutes hard/3 minutes recovery

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METABOLISM-REVVING STRENGTH CIRCUITS

2 Days a Week

This nonstop strength routine burns about 25% more calories than traditional weight lifting, which usually includes longer breaks. The higher intensity can boost your metabolism for up to 38 hours postworkout. (Related: Best Metabolism-Boosting Foods)

How it Works Warm up by marching in place for 3 minutes and doing 5 reps of that day's exercises without dumbbells. Then pick up your weights and do 10 to 12 reps (unless otherwise noted) of each exercise in the order given, taking a 15-second rest between moves. That's 1 circuit. Do 2 or 3 circuits, resting for a minute after each. For best results, always engage your core muscles to stabilize your torso before beginning each exercise.

Fit Tip You should use dumbbells that are very challenging to lift as you do the final reps of each exercise. If you feel as if you could do more than the recommended number of reps, you need a heavier weight. The amount of weight you lift may vary, depending on the exercise.