Skull crushers are a strength training staple — but are you sure you’re even doing the exercise correctly?
For this basic gym necessity, you shouldn’t settle for anything other than perfect form. Let Men’s Health Fitness Director Ebenezer Samuel, C.S.C.S., guide you through the exercise’s subtleties, saving you from the bad habits that are keeping you from unlocking your fitness potential.
Grab your dumbbells (or E-Z bar or barbell), then get ready to blast your triceps. Just remember to concentrate on your grip — you don’t want to drop the weights and literally crush your skull.
Eb says: Maintain a sturdy body position: Feet flat on the floor, squeezing your glutes, and keep your core active so that you’re not arching your back on the bench. I know, I know; we always say you shouldn’t arch your back, but it’s more important to get the most out of the skull crusher. You want, at the minimum, a perpendicular upper arm angle relative to your torso; anything less than that, and your arm action misses the point of the skull crusher. If you arch your back, it’s harder to find that proper angle.
Eb says: Once you have the bar over your head, drive your shoulders aggressively into the bench and maintain a little bit of tension in your mid-back. Then lean your upper arms back just slightly. Typically, you’ll see people aim to keep their upper arms perpendicular to the floor; I want you to be at a 91- or 92-degree angle instead. That slight shift places more tension on the triceps when you straighten your arms and prevents the straight-armed position from being a position of rest. Now you need to fully flex your triceps to maintain straight arms.
Eb says: As you lower the weight, work to keep your elbows in. Your elbows and wrists should both be shoulder-width apart; not closer or farther apart. It’s common for people to let their elbows flare out as they’re doing skull crushers; avoid this. That’s a good way to injure your shoulders and it also takes the emphasis off your triceps, diminishing the effectiveness of the move.
One Lever Only
Eb says: Once you’ve gotten into this position, lower the bar to your head, moving only at the elbow joint. It’s tempting to let your upper arms roll back as you lower the bar toward your forehead, then shift your upper arms forward as you drive the weight back up, but that takes the emphasis off your triceps and gets your lats involved. You’re aiming to move only at the elbows, maximizing the work your tris have to do.
By Brett Williams