Leave it to Jennifer Lopez‘s trainer David Kirsch to come up with a hardest push-up variation I’ve ever seen—and then make it look super easy. Kirsch, who has worked with J.Lo for years, demonstrates how to take the exercise from level 6 to, like, level 13. To be honest, I think I’m already sore from just looking at it.

Kirsch says he likes to take time in the morning to block out the noise and zone in on his mind-body connection—particularly with this push-up that’s so tough that literally no part of his body ever even touches the floor. In the video, he holds himself up a few feet above the ground with stacked blocks while his feet are resting on an elevated base, shifting more of his body weight onto his arms. Then, he does a mix of knee tucks and spiderman push-ups as he performs his hardest push-up variation.

Obviously this exercise isn’t for push-up newbies. If you’ve yet to master the standard technique, consider that a prerequisite before attempting the hardest push-up variation. But when you’re ready to get arms like J.Lo, here’s exactly how to do the move.

How to do the hardest push-up variation we’ve ever seen

• Build two even stacks of blocks—one to go under each hand during your push-ups. Make sure they’re at the right distance between your arms so you can keep proper push-up form.
• After securing a hand on each stack, slowly bring your legs up onto an elevated surface behind you. It could be a chair, couch—anything that’s stable and higher than your stacked blocks. Be sure there’s enough distance between the stacks and your feet for your body to stay straight.
• Lower your body down into a push-up. At the same time, tuck your left knee into your chest. As you raise your body back up, slowly kick your leg back into the air behind you. It should be hovering a couple feet above your elevated surface. Repeat five times.
• Without taking a break, bring your left knee in toward your left hand for a spiderman push-up. As you push back up, bring your leg back and hover your foot slightly above the elevated base. Repeat five times.
• Once you’re finished with push-ups using your left leg, repeat the same sequence on your right leg.

Here’s how to do a regular push-up the right way:

Meet ‘pseudo planche’ pushups—the move that seriously strengthens your biceps and shoulders. Then if pushups tend to hurt your wrists, try this one modification that might be able to help.