The triceps-busting move that will light your entire arm on fire

Name a workout move that sounds more badass than a skull crusher. Whether you’re on a bench at the gym or on the floor at home, this next-level tricep extension will give your arms a serious burn, so grab a weight and get ready to add it into your push-day repertoire.

The move builds strength through back of your arms, which Isaiah Harmison, a Houston-based Barry’s Bootcamp instructor, says helps you perform bigger movements. “Your triceps are very good for pressing movements,” he explains. “So working your triceps is going to help you with your bench press, it’s going to help you with push ups. It’s going to help you with basically anything you’re pushing away from yourself.”

A skull crusher is different than a normal tricep extension because instead of standing upright, you do it lying down on your back on a bench or the floor with a weight above your head. To ensure you don’t literally crush your skull (because, uh, yikes), there are a few form-related things worth keeping in mind.

Grab a dumbbell, and lay on your back with your hands interlocked around one of the rubber ends of the weight. “The only muscle you should be working in this movement is your tricep,” Harmison says. Start with your arms extended above your head, and then hinge at the elbows, bringing the weight down towards your head. When you reach the bottom of the move, extend straight back up. You can also do the move with a bar, but Jackie Vick, NCSF, certified personal trainer for GOLD’S AMP app, recommends using an an EZ bar (aka the squiggly looking one).  You’ll take the same form described above, and grip the bar with your hands shoulder-width apart, keeping your core tight and your back against the bench.

To amp things up, Harmison says that instead of keeping your elbows right over your shoulders, you can press your elbows back towards the top of your head. “It helps elongate and extend the tricep a little bit more make it a little bit harder,” Harmison says. But to do this variation,  Harmison says you’ll want to be on a bench so you can bend the weight behind your head without the floor getting in the way.

Do all of this, and, ya know, avoid dropping the weight on your head, and your arms will thank you for it. Once they get over the soreness, that is.

This 15-minute arm workout uses just a resistance band, and this is the absolute hardest lower body compound move that you could do.