Incinerating fat is mission number one at S10 Training, a private studio in New York City. “We use a body composition analyzer [a souped-up scale that measures with bioelectrical impedance analysis] to read how much muscle, visceral fat, body fat, and water weight you have an how many calories you burn at rest,” says S10’s founder, Stephen Cheuk. “This data allows you to train smarter, so you’re not doing a workout that doesn’t net results.”

You may not have such high-tech trackers, but you can benefit from all the number crunching that S10 has done to maximize the fat-burn in its workouts. Getting into that optimal melting zone, Cheuk says, boils down to shocking the body with a physical challenge it hasn’t adapted to yet. “Every workout should feel like the first week you came to the gym,” he says.

Cheuk created this high-insenity routine using just gravity and body weight to spark your fat burners as you sculpt every muscle. You’ll alternate between a one-minute compound strength move and a 30-second cardio burst. Max your burn by working a little harder and faster each round. (And if this is the kind of workout you love, you’ll go gaga over our 30-day heart-rate boosting HIIT challenge.)

How it works: Warm up, then complete the exercises in order. Repeat the circuit two more times.

Total Time: up to 30 minutes

You will need: No equipment

1. Walk-Out Chaturanga

 A

A.Stand with feet hip-width apart and arms by sides. Fold forward and walk hands out until body is in a plank.

B.Bend elbows to lower chest to floor, then scoop chest forward and up, arching back, straightening arms, and rolling forward onto tops of feet (thighs are off floor) to come into upward-facing dog.

C.Reverse the entire movement back to start.

Sets:3

Reps:AMRAP for 30 seconds

2. Fast Feet

 A

A.Stand with feet wide, knees slightly bent, and elbows bent by sides. Quickly alternate lifting feet slightly off floor, shift- ing weight from left to right on balls of feet. Continue alternating as fast as you can.

Sets:3

Reps:AMRAP for 30 seconds

3. Single-Leg Hip Raise

 A

A.Stand with feet hip-width apart and hands on hips. Lift straight left leg to hip height. Lower. Switch sides; repeat. Continue alternating sides.

Sets:3

Reps:AMRAP for 1 minute

4. Mountain Climbers

 A

A.

Start on floor in plank on palms. Quickly pull right knee toward chest. Immediately switch sides; repeat. Continue alternating sides as fast as you can.

Sets:3

Reps:AMRAP for 30 seconds

5. Alternating Lunge

 A

A.

Stand with feet hip- width apart and hands on hips. Step right foot forward, bending legs until each forms a 90-degree angle. Push into right foot to return to standing. Switch sides; repeat. Continue alternating sides

Sets:3

Reps:AMRAP for 1 minute

6. Standing Big Sprint

 A

A.

Stand with feet hip- width apart and arms by sides. Pull right knee to hip height, swinging arms out to sides at shoulder height.

B.Quickly switch legs, lowering arms to sides. Continue alternating high knees and arm swings as fast as you can.

Sets:3

Reps:AMRAP for 30 seconds

7. Russian Push-Up to Push-Up

 A

A.

Start on floor in plank on palms. Bend elbows straight back until forearms touch floor, then push up to start.

B.Next, bend elbows 45 degrees out toward sides until chest grazes floor. Push up to start.

C.Continue alternating Russian push-up with standard push-up for 1 minute. (If this is too tough, drop to your knees and still go for full range on every rep.)

Sets:3

Reps:AMRAP for 1 minute

8. Skater Toe Touch

 A

A.

Stand with feet hip- width apart, knees soft, and arms by sides to start. Jump as far to left as you can, landing on left foot (knee soft) and swinging right leg behind left leg as you reach right fingertips to touch floor in front of left foot.

B.

 Immediately switch sides, pushing off left foot to jump right and landing on right foot as you touch left fingertips to floor. Continue alternating sides as fast as you can.

Sets:3

Reps:AMRAP for 30 seconds

9. Bear Crawl

 A

A.

Stand with feet wide and arms by sides. Fold forward and plant hands about 3 feet in front of feet.

B.Keeping hips back, bend elbows and knees slightly (almost as if you’re in downward dog). Maintain this shape as you walk hands and feet forward as fast as you can.

Sets:3

Reps:AMRAP for 1 minute

10. V-Up

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A.

Lie faceup on floor with legs extended and arms by sides to start. Lift straight arms and legs simultaneously until body forms a V. Lower to start

Sets:3

Reps:AMRAP for 1 minute

11. Gymnastic Ab Pulse

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A.

Sit on floor with legs extended and hands on floor (touching only with fingertips) in front of hips. Raise straight legs about 3 inches above floor to start. Pulse legs about 6 inches up and down (without touching floor).

Sets:3

Reps:AMRAP for 30 seconds

12. Hollow-Back Hold

 A

A.

Lie faceup on floor with legs long and arms extended overhead. Keep lower back pressed into floor as you lift arms and legs so body forms a C.

Sets:3

Reps:Hold for 1 minute