The 15-minute belly-blaster workout

Combine cardio and standing abs moves for an intense, waist-whittling routine that will tighten your tummy fast.
© 2014 Weider Publications // © 2014 Weider Publications

While it's true that you can't spot reduce, research shows that high-intensity interval training (HIIT) may be more effective than traditional cardio at getting rid of stubborn abdominal body fat. Plus, strengthening your core muscles can help create flatter, more drawn-in abs and improve your posture, contributing to a slimmer, sexier waistline. So get ready to blast off belly fat with this 15-minute circuit that combines fat-scorching cardio intervals with standing core exercises that do double-duty as your active recovery.

How it works: Do as many reps as possible (AMRAP) of each exercise, in order with no rest. (The core strength moves double as the warm-up, recovery and cool-down.) Repeat the circuit 3 times total.

You will need: No equipment

--By Jessica Smith

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Squat to knee lift twist

A. Stand with feet hip-width apart, arms by sides. Lower into a deep squat, sitting back into hips and extending arms in front of chest with palms facing in.

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Squat to knee lift twist

B. Stand up out of squat, balancing on left leg and lifting right knee in front of hip, as arms extend to sides of shoulders and upper body rotates right. Return to start. Repeat, switching sides.

Tip: Inhale during the squat and exhale on the twist, drawing abs in tighter to spine on exhalation.

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Side leap and balance

A. Balancing on right leg, lower into a single-leg squat with right arm driving forward, left arm back, elbows bent.

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Side leap and balance

B. Push off right foot and leap up and over to left foot, swinging arms open to sides of shoulders (imagine jumping sideways over a large puddle), landing in a single-leg squat on left leg with left arm forward. Hold for 1 count. Repeat to opposite side.

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Crossing climber

Begin in plank position with feet hip-width apart. Bend one knee across to opposite elbow (tapping knee to arm if possible), then quickly jump to switch legs.

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180 squat jump

A. Stand with feet hip-width apart. Lower into a squat, swinging arms back by hips. Quickly jump up and over to the right, turning body 180 degrees mid-air, swinging arms in front of body for momentum.

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180 squat jump

B. Land in squat position, swinging arms back by hips. Immediately repeat on opposite side.

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Standing straight leg bicycle

A. Stand with feet together, knees slightly bent, hands clasped behind head and abs engaged.

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Standing straight leg bicycle

B. Balancing on left leg, extend right leg out low in front of body, toe pointed, as upper body twists to right. Return to start; repeat on opposite side.

Tip: Inhale when feet are together and exhale on rotation, drawing abs in tighter on exhalation.

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