This chest workout consists of only one exercise—the pushup—but it’s hard as hell. That’s because it uses varying tempos to cumulatively challenge the same muscle groups, says Men’s Health Fitness Director BJ Gaddour, C.S.C.S.

First, you’ll go as fast as possible, cranking out as many reps as you can in a row. This tempo provides constant tension in your pecs, maximizing muscle growth, he says.

Once you can’t perform another explosive rep, you’ll immediately perform an isometric hold, hovering a few inches off the floor.

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Compartmentalize, and hold this position for as long as you can. You’re building strength and stability in the hardest point of the pushup—the bottom, explains Gaddour.

Finally, do as many eccentric pushups as possible. Take 3 seconds to lower your body to the floor, and then drop your knees to the floor and quickly cheat your way back up to the top of a pushup position. Don’t pause between reps. 

Studies show that slowly lowering your bodyweight stimulates growth and boosts strength throughout your chest, says Gaddour. 

You’re done when you can’t complete 1 more rep and your pecs feel as if they’re about to pop out of your shirt.