Barbell One Leg Squat
- Target muscle
- Quadriceps
- Synergist muscles
- Adductor Magnus, Gluteus Maximus, Soleus
- Equipment
- Barbell
- Body part
- Thighs
- Type
- Strength
The barbell one leg squat is a single-leg strength exercise that loads one quad at a time with a barbell racked across your upper back. The working quadriceps drive the movement, with the gluteus maximus, adductor magnus, and soleus assisting. It builds single-leg strength, balance, and corrects side-to-side imbalances that a regular two-leg squat can hide.
How to do the Barbell One Leg Squat
- 1Set the barbell in a rack at upper-chest height and load it for your single-leg strength, which will be lighter than a normal back squat.
- 2Step under the bar, rest it across your upper traps (not your neck), grip it just outside your shoulders, and unrack it by standing tall.
- 3Take a step back and set up on one leg, placing the rear foot on a bench or low box behind you so the working front leg carries the load.
- 4Brace your core, keep your chest up, and look straight ahead with the front foot flat on the floor.
- 5Lower under control by bending the front knee and hip, sinking until your front thigh is roughly parallel to the floor.
- 6Keep your front knee tracking in line with your toes and your torso upright; let the rear knee drop toward the floor without resting on it.
- 7Drive through the heel and midfoot of the front leg to stand back up, fully extending the hip and knee.
- 8Finish all reps on one side, then switch legs and repeat. Re-rack the bar safely by walking it back into the hooks.
- 9Use a power rack with the safety arms set just below your bottom position, or have a spotter ready in case you lose balance.
Form tips
- Find a fixed point at eye level to stare at — single-leg balance is far easier when your gaze is steady.
- Keep most of your weight on the front foot; the rear leg is for balance, not for pushing.
- Start light and master the balance and depth before adding load, since the limiting factor is stability, not raw quad strength.
- Always work inside a power rack with the safety arms set, or use a spotter, because a balance slip under a barbell is hard to recover from.
- Match the rep count exactly on both legs to even out left-to-right strength differences.
Common mistakes
- Letting the front knee cave inward instead of tracking over the toes, which stresses the knee joint and leaks force out of the quad.
- Pushing off the rear foot to help stand up, which shifts work away from the target front-leg quad and defeats the purpose of the lift.
- Going too heavy too soon, so balance fails before the muscle does and form falls apart.
- Leaning the torso too far forward, which shifts load off the quads and onto the lower back.
- Skipping the rack safeties or a spotter on a heavy set, leaving no bailout if you lose your balance mid-rep.
Frequently asked questions
What muscles does the barbell one leg squat work?
It primarily works the quadriceps of the working leg, with the gluteus maximus, adductor magnus, and soleus assisting as synergists.
Is the barbell one leg squat good for beginners?
It can be, but balancing a barbell on one leg is demanding. Beginners should master a bodyweight or goblet single-leg squat first, then add a light barbell once the balance and depth are solid.
How is this different from a regular back squat?
The back squat loads both legs at once, while the one leg squat works a single quad at a time. The single-leg version uses much lighter weight, builds balance, and exposes side-to-side strength imbalances.
How many sets and reps should I do?
For strength and balance, 3–4 sets of 6–10 reps per leg works well. Keep the load light enough that your balance and form hold for every rep on both sides.
How do I stay safe under the bar on one leg?
Train inside a power rack with the safety arms set just below your lowest point, or use a spotter. That way you can bail the bar onto the safeties if your balance gives out.
