Barbell squat: how to do it and how much you should lift

Muscles the squat works

The squat works 3 muscle groups hardest: the front of the thigh (quadriceps), the glutes and the inner thigh (adductors). In a 10-week study that measured the muscles on MRI scans, squats grew all 3. They did not grow the hamstrings, or the one quad muscle that also crosses the hip (rectus femoris).

Depth changed the result. Full squats grew the glutes by 6.7% and the adductors by 6.2%. Half squats grew them by 2% to 3%. The quads grew by about 5% either way.

Your lower back works hard too, but to hold your trunk still, not to move the weight. Studies that measure electrical activity with sensors on the skin (EMG) show which muscles fire, not which ones grow. The hamstrings fire in a squat, yet they did not grow in the MRI study.

How to squat

1. Set the bar in the rack at about the height of your mid-chest. Set the safety arms a few centimeters below where the bar sits at the bottom of your squat.
2. Step under the bar and set it on your upper back. For a high-bar squat it sits on top of your traps. For a low-bar squat it sits lower, across the back of your shoulders.
3. Grip the bar a little wider than your shoulders and squeeze your shoulder blades together, so the bar sits on muscle, not bone.
4. Stand up to lift the bar off the hooks. Take 2 or 3 short steps back and set your feet about shoulder width apart, toes turned out a little.
5. Take a big breath into your belly and brace your trunk, as if someone were about to push you.
6. Bend your hips and knees together and sit down between your heels. Let your knees travel forward and out, in line with your toes.
7. Go down until the crease of your hip is level with the top of your knee or lower, as deep as you can keep your heels down and your back set.
8. Stand up by pushing the floor away through the middle of your foot, with your hips and chest rising together. Breathe out at the top, then brace again for the next rep.

Under IPF powerlifting rules, the hip crease must go below the top of the knee, and the bar can sit no lower than the back of the shoulders. One descent per rep, no double bounce at the bottom.

Where the advice differs

Most squat technique is coaching habit, not tested in studies. Where coaches disagree, the right answer depends on your build, your joints and your goal.

Common mistakes and how to fix them

Sets, reps and rest for the squat

There is no single right number. The table is a starting point built on the research, not a rule any one study tested.

What the studies show:

• Heavy weights build more strength. Muscle grows about as well with light or heavy weights, if the sets go close to failure.
• More weekly sets bring more muscle, up to a point. Strength gains level off sooner.
• Squatting 2 times a week helps you fit in more sets. With the same weekly sets, training a muscle more often does not add size.
• You do not need to reach failure. A squat missed without safety arms is a safety problem, not only a tiring one.
• Experienced lifters judge how close a heavy squat is to their max better than beginners. That is what RPE measures.

For longer answers, read how many sets and reps build muscle and how long to rest between sets.

Warm-up sets before a heavy squat

Warm up with the bar, then climb towards your working weight in a few short sets. Type your working set below, and the calculator gives you the warm-up sets and the plates for each side.

The calculator uses a common ramp: the empty bar for 10, then about 40% for 5, 60% for 3 and 80% for 2. Before sets of 5 or fewer reps, or a working weight of 100 kg (225 lb) or more, it adds 90% for 1. Before sets of 8 or more reps, it keeps only the 40% and 80% sets. It rounds each weight down to what your plates can make, and skips a set that would sit within 5 kg (10 lb) of the one before.

Only one part of that ramp has studies behind it. In trained men, a warm-up set at 80% of the working weight gave faster squat sets than a warm-up at 40%. Another study found that the kind of warm-up made no difference to squat reps. The other steps are habit, and no study shows that warm-up sets prevent injury.

How much should you squat for your weight?

The table shows where each level starts, as a one-rep max (1RM), for ages 18 to 29. 1RM is the most weight you can lift once. These are Trackist's own strength standards, the same ones the strength calculator and the app use.

Trackist scores the back squat in one group with the other loaded squats. The front squat, the paused squat, the Smith machine squat, the goblet squat, the belt squat and the pendulum squat meet the same lines. The leg press and the hack squat are not scored, because a machine sled moves far more weight than a bar on your back. The standards were written from published coaching tables, rounded, and they describe people who train, not everyone.

After 29, the lines drop: by 5% in your 30s, 12% in your 40s, 20% in your 50s and 30% from 60. The strength calculator adjusts for your exact age and scores all 4 main lifts.

Why other tables give different numbers:

• Strength Level builds its table from lifts its users log. Its intermediate man squats 1.75 times body weight, and its intermediate woman 1.25 times. Ours start intermediate at 1.5 and 1 times.
• A study of 809,986 powerlifting meet entries found that the strongest 10% of men aged 18 to 35 squat 2.83 times body weight, and women 2.26 times. Meet lifters are stronger than people at a typical gym.
• Each table uses a different group of people and different cut-offs, so a level in one does not match a level in another.

Under 18? The table is for adults, and it sets no target for teenagers. For a young lifter, clean reps to full depth and slow, steady progress matter more than any number on it.

Find your squat max

You do not need to test a true one-rep max to know it. Type a set you did, and the calculator estimates your max with 7 formulas. Sets of 10 reps or fewer give the closest estimate. For more detail, open the 1RM calculator.

Squatting safely without a spotter

A failed squat is safe when something catches the bar before you do. Set that up before you load the bar.

• Squat inside a power rack with safety arms or straps. Set them a few centimeters below where the bar sits at the bottom of your squat. Test the height with the empty bar.
• If you get stuck, sit down under control until the bar rests on the safety arms, then slide out from under it.
• Without safety arms, the way out is to drop the bar behind you while you step forward. Practice it with an empty bar and a clear space behind you before you ever need it.
• A spotter stands close behind you, with their arms under yours, ready to help you stand up. Agree before the set when they should step in.
• Stop a rep or 2 short of failure when you train alone.

When the squat hurts

Pain is a reason to change something, not to push through. Diagnosis and treatment belong to a physiotherapist or a doctor.

• Knee: squat to a box at a depth that does not hurt, use less weight and build back down over a few weeks. Knee load rises as the knee bends, so depth is the first thing to change. The front squat put less load on the knee than the back squat, with similar muscle work.
• Lower back: check that you brace before each rep. Try a high-bar or front squat, which keep your trunk more upright, or raise your heels a little.
• Hip pinching at the bottom: widen your stance, turn your toes out a little more, and stop just above the depth that pinches.
• A sudden sharp pain, a pop or a knee that gives way needs a doctor soon.

In powerlifting, the back, the shoulder and the knee are where injuries happen most. The rate is about 1 to 4 injuries per 1,000 hours of training, similar to other sports without contact. For lasting pain, read what to do when a lift hurts.

Squat variations and alternatives

In Trackist's exercise library, the barbell back squat sits in one group with 11 other squat movements: the goblet squat, the front squat, the hack squat, the Smith machine squat, the leg press, the bodyweight squat, the bodyweight box squat, the wall sit, the paused back squat, the belt squat and the pendulum squat. The app's squat page lists them as similar movements. When you swap the squat for one session or for the rest of your plan, the picker puts that group first, then other quad exercises, starting with those your equipment and joints allow.

How Trackist runs your squat

Trackist is an AI personal trainer for the gym. It writes your plan, and the squat gets this from the app:

• From your second session of the squat, Trackist suggests what to try from the last time you logged it. When every set at your top weight reached the top of the rep range, it adds 2.5 kg (5 lb). Inside the range, it keeps the weight and asks for more reps. There is no suggestion in a deload week.
• When you fall short of the reps, it keeps the weight, takes about 5% off or leaves the call to you, depending on how far short you fell and how hard the sets felt.
• From your second session, it logs a personal record when you beat your heaviest weight, your most reps at a weight or your best estimated max.
• The exercise page shows 4 form cues, the muscles worked and the joints the squat loads: knees, lower back and hips. From your second session, it adds a chart of your estimated one-rep max.
• When your knee hurts on the squat, you report it, rate it from 1 to 5, and Trackist swaps the squat for an exercise that spares the knee, usually one that trains the same muscle. Your profile remembers that deep knee bends hurt, so later plans leave out squats and lunges that load the knee, and keep hip hinges such as the Romanian deadlift.
• When you set up a plan, you can mark barbell back squats as a movement to avoid, and the coach picks other leg exercises for the plan.
• Your squat counts towards your Strength Score in the squat group, with the same standards as the table above, adjusted for your age.