Photo: Ryan Kelly / Daily Burn

It’s a tried-and-true move for a reason: It hits the spot when you’re looking for a workout to quite literally kick your butt. We’re talking about the functional, no-frills squat. The multi-joint move works your glutes and quads and can strengthen your hamstrings, too.

But there’s just one problem—most people are doing it wrong.

For starters, squatting down far enough (aka scoring good squat depth) is key. “If you don’t get a lot of hip flexion during the squat, you won’t use your glutes. Depth of squat matters a great deal in terms of improving your glutes and hamstrings,” says Mike Boyle, co-founder of Mike Boyle Strength and Conditioning and author of New Functional Training for Sports.

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Squat Science: The Right Technique 

To fire up your muscles in all the right places, here is Boyle’s breakdown of the squat, from the ground up. 

Your lower body: Standing with your feet slightly wider than your hips and with your toes turned out, squat down to a point where your femur (thigh bone) is parallel to the floor. Your kneecap should be almost directly over your big toe at the bottom of the squat. And, as you squat, your knees should get progressively further apart. That’s a sign that the right muscles are doing their job as you descend, he says. (So as you stand at the top of the squat, your knees might be 12 inches apart, but at the bottom of the squat they might expand to 18 inches apart.) Your weight should be distributed across your mid-foot to your heel. If you’re on your toes? Sit further back into your squat to shift your weight to your heels.

Your upper body: “Some people squat like a melting candle—everything sort of falls,” he says. It should go without saying that that’s not the right form. While it’s impossible to squat straight up, your body should lean forward about 45 degrees, Boyle says. If you’re dropping forward more than that, you might not have the mobility to do a full-depth squat in the first place. Do not pass go, do revisit some of the mobility work below.

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Fine-Tuning Your Squat

To squat well—and safely—follow these guidelines from Boyle.

Practice mobility. Sitting in a squat position is Boyle’s number one recommendation to improve your mobility. Hold onto a door jam or rack in the gym and sit in a deep squat. While descending, try to really arch your back. “You won’t be able to, but attempting to arch will help you maintain a more neutral spinal position,” says Boyle. When you’re in the squat, gently rock back and forth and side to side. “For true mobility, you have to rock that joint in multiple directions,” he says.

Count breaths, not reps. When you’re doing the mobility exercise above, you’re going to think about breathing. This will encourage you to relax more during the exercise, says Boyle. Inhale through your nose for three counts, then exhale for five. Repeat 3-4 times for 20-30 seconds total.

RELATED: 7 Ways to Improve Your Squat

Then, add weight. As physical therapist Gray Cook puts it, there’s no sense in “adding strength to dysfunction.” However, once you’ve successfully mastered squat mechanics it’s time to add resistance. Why? “If you want your muscles to make adaptations and get stronger, you have to force them to do that,” says Boyle. That is, he adds, unless you’re happy with where you’re at now and don’t want to improve. (Anyone?) A good starting point is doing goblet squats with a dumbbell or kettlebell.

Or, take it up a notch. Once you can comfortably squat your bodyweight 20 times, Boyle suggests moving on to single-leg variations. “Life is a game played on one foot. We go up the stairs one foot at a time, and everything we do in sports is one foot at a time,” he says. Start off with split squats (a “stationary” lunge where one foot is in front of the other and you drop down to a lunge position and press back up).

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Want more ways to drop it low? Check out these six squat variations to build size and strength.

This article originally appeared on DailyBurn.com.