If you want a bigger bench press, it's time to pay attention to a tiny muscle called the serratus anterior, says Men's Health Fitness Director BJ Gaddour.

Your serratus anterior -- also known as your "punching muscle" -- sits on the side of your ribcage and is responsible for pulling your shoulder blades forward whenever you press a weight, perform a pushup, or throw a jab, Gaddour explains.

Strengthening the small muscle lets you lift heavier loads, bang out more reps, and hit harder, he says. It also bulletproofs your shoulder joints by taking the strain off of your delicate rotator cuff muscles.

Related: 3 Reasons You're Not Benching Bigger Numbers

It's difficult to engage your serratus with a regular upper-body routine, though. That's why Gaddour recommends hitting them directly with the serratus punch. Watch the video to see how to perform the movement with perfect form.

Looking to keep your metabolism running at full speed? Try these 10 Exercises That Burn More Calories Than Running.

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