Want to lose your spare tire? Then think fast.

Superfast exercises build up lactic acid in your muscles because you're working harder and faster than your body can clear the compound. This spurs human growth hormone, which boosts fat loss and muscle building, and elevates your metabolism.

21-Day Metashred: At-Home Program To Strip Away Fat And Reveal Lean, Hard Muscle

In fact, a 30-second sprint is enough to increase your level of growth hormone by 530 percent. A high-intensity workout filled with fast-paced moves can keep your metabolism cranking for up to 24 hours.

And you don't even need weights to get the effect. Take this lightning-fast metabolic complex from Andy Speer, C.S.C.S., owner of SoHo Strength Lab in New York City, shown in the video above. It requires no equipment and you can do it in 15 minutes or less.

How to do it: Perform each movement for 45 seconds, resting 15 seconds between exercises. Do 3 to 5 rounds.

1. Skater jump
2. Lateral bear crawl to jump
3. Lateral pogo
4. Ski jump
5. T-pushup

More Men's Health:
-- This Man Stretched 10 Minutes A Day For A Month ... Here's What Happened
-- A One-Move Workout Will Make Quads, Glutes And Abs Scream
-- 30-Minute Insane Interval Workout
-- The J.J. Watt Workout

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