Barbell squat: how to do it, muscles worked and common mistakes

The squat is one of the most complete exercises in the gym. It trains a large part of your body in a single movement and is the backbone of any serious leg day. In this guide you'll learn which muscles it works, how to execute it safely, and the mistakes to avoid.

Which muscles the squat works

The squat is a multi-joint movement, so it recruits a lot at once:

• Quads: the main drivers extending the knee on the way up.
• Glutes: heavily involved at the bottom and in hip extension.
• Hamstrings: help stabilize and extend the hip.
• Core and lower back: work the whole time to keep your torso rigid.

Because it recruits so much muscle mass, the squat burns plenty of energy and gives a strong training stimulus, which helps with both muscle gain and fat loss.

Step-by-step execution

Setup

1. Position the bar on your upper back, resting on your traps, never on your neck.
2. Set your feet about shoulder-width apart, with your toes turned slightly out.
3. Before unracking, take a big breath into your belly and brace your core, as if bracing for a punch to the stomach. That's the bracing cue.

The descent and drive

1. Push your hips back and bend your knees at the same time, like sitting into a chair.
2. Lower under control, keeping your chest up and your spine neutral.
3. Go to at least thighs parallel to the floor (or slightly below if your mobility allows).
4. Drive back up by pushing the floor away through your whole foot, extending knees and hips together.

Hold your breath on the way down and exhale only near the top. This keeps your torso stable through the hardest part of the rep.

Depth and spine position

Hitting parallel is plenty of stimulus for most people. Going deeper is only worth it if you can keep a neutral spine and your heels down. If your lower back rounds at the bottom (the classic "butt wink"), you've gone past your current mobility. Cut the range or work on ankle and hip mobility.

Common mistakes

• Knees caving in (valgus): actively push your knees out toward your toes throughout the rep.
• Heels rising off the floor: usually limited ankle mobility. Keep your weight through the midfoot and heel, not the toes.
• Rounding the lower back: a sign of too much load or weak bracing. Drop the weight a bit and tighten your core.
• Hips shooting up first: this tips your torso forward and overloads your lower back. Rise with hips and shoulders together.

Sets and reps

If you're starting out, prioritize technique over load. A solid starting point:

• Beginner: 3 sets of 8 to 10 reps with a light to moderate weight.
• Intermediate: 3 to 4 sets of 6 to 12 reps, adding load gradually.

Log what you used each session and try to beat it next week, whether with more weight or more reps. In Health & Lifts you log your sets and Dumbell, the app's AI coach, tells you when it's time to add load.

Safety

If you train alone, use a rack with the safety pins set at the right height, so you can bail on the bar if you can't stand up. Warm up before heavy sets, and if you feel joint pain or have a history of injury, get guidance from a qualified coach or physiotherapist.

Conclusion

The squat is a long-term investment: nailing your technique now pays off for years. Start light, film your form, fix the details, and add load patiently. Pair it with the deadlift and the bench press for a balanced strength routine.