A yoga pro explains the correct way to do chair pose in order to truly work that bum

I like yoga just as much as the next person. You get the meditative, mind-boosting benefits as well as the physical perks, and going through a couple of flows works your whole body without requiring you to push it too hard (sorry, HIIT class)—not to mention that post-vinyasa feeling is as chill as it gets.

That’s not to say that, while it’s definitely gentle and low impact, it doesn’t fire up numerous muscles. In fact, certain yoga positions rival the most intense strength training moves—like chair pose, for example, which can work your glutes and quads about as well as any old squat. Whenever my yoga instructor demands that the class segue way into chair, I always cringe because of how it burns my bum (plus it’s also targeting your ankles, calves, and back while opening up your chest and shoulders—phew).

But—despite how multi-beneficial the move is—there are plenty of ways to do it incorrectly, therefore nixing all of its muscle-strengthening perks. “The wrong way is when the knees collapse towards one another, the knees are past the ankles, and the lower back is rounded,” explains Francesca Valarezo, obé fitness yoga instructor.  “Then your shoulders are collapsing, the chest is collapsing, and the vision is down.” So basically you don’t want to curve your body downwards or bend back too far.

The good news? “Doing it the right way actually feels better,” says Valarezo. This is what the correct chair pose looks like: “Your feet are together, your toes are spread wide, the knees are in line with the ankles—and you’ll know that because you’re able to see your feet,” she says. “You’re sitting with your buns back, there’s a gentle arch in the low back and there’s an arch at your chest. The crown of the head and the tail are at a diagonal line. Now, the arms can lift easily, the lungs lift, the armpits lift, the fingertips reach, and the vision goes up.” Boom—so it’s all about reaching and looking up rather than down. This way, you’ll work that peach even more efficiently—watch out, J-Lo.

If you’re new to vinyasa, here’s how to modify yoga poses for beginners. And these are detoxifying yoga poses that wring out your whole body.