Barbell Back Squat: How to Do It, Muscles Worked & Form

The barbell back squat is the cornerstone lower-body strength exercise. Loading the bar across your upper back lets you move serious weight through a full range of motion, which is why it builds the quads, glutes, and posterior chain faster than almost any other lift. This guide covers exactly how to set up, descend, and drive out of the squat with safe, repeatable form.

Muscles Worked

The back squat is a compound, closed-chain movement that trains the entire lower body and bracing musculature:

• Quadriceps: primary driver out of the bottom and through the knee.
• Gluteus maximus: extends the hips to lock out the rep.
• Hamstrings & adductors: assist hip extension and stabilize the knee.
• Erectors & core: keep the spine rigid under load.

How to Do a Barbell Back Squat

1. Set the bar in the rack at upper-chest height, grip just outside shoulder width, and pin the bar across your upper traps. Step under, brace, and unrack by standing tall.
2. Take two short steps back and set your feet shoulder-width apart with toes turned slightly out.
3. Take a big breath into your belly, brace your core, and break at the hips and knees together to descend.
4. Lower under control until your hip crease drops below the top of your knee, keeping your torso angle stable.
5. Drive through your whole foot and stand back up to lockout, exhaling near the top. Repeat for reps, then re-rack.

Coaching Cues

• "Spread the floor": push your knees out in line with your toes.
• Keep your whole foot planted; drive from mid-foot, not the toes.
• Brace before you descend, not on the way up.
• Move down and up at the same hip-to-knee ratio to keep the bar over mid-foot.

Common Mistakes

• Knees caving in: strengthen the glutes and cue knees out.
• Heels rising: usually ankle mobility or stance too narrow.
• Cutting depth: reduce load until you can reach parallel or below.
• Good-morning squat: hips shoot up first; keep the chest and hips rising together.

Sets, Reps & Programming

For strength, work in the 3–6 rep range for 3–5 sets with longer rest. For muscle growth, 8–12 reps for 3–4 sets. Add weight gradually once you can complete all prescribed reps with clean depth and a stable torso.

Safety

Always squat inside a rack with the safety pins set just below your bottom position so you can bail safely. Warm up the hips and ankles, and ramp up in weight rather than jumping straight to heavy loads.

Track It in LiftLogic

LiftLogic logs every set, tracks your squat progress over time, and tells you when to add weight. Download LiftLogic free on the App Store.