Barbell Hack Squat
The barbell hack squat is an old-style squat in which you hold a barbell behind your legs with straight arms and stand up with it from the floor, the bar travelling up the backs of your calves and thighs. It works the quadriceps above all, with the glutes, back muscles and grip helping, and it is a barbell-only way to bias the quads without a hack squat machine.
Also called: Hack Squat Barbell, Behind-Back Barbell Squat, Hackenschmidt Squat, Behind-the-Back Deadlift Squat · Equipment: barbell · Pattern: squat
Step by step
- Set a barbell on the floor, or on low blocks at about mid-calf height, and stand just in front of it with your heels close to the bar and your feet about hip-width apart.
- Squat down with your chest up and reach back to grip the bar just outside your legs, palms facing backwards.
- Straighten your arms, set a flat back, look straight ahead and brace your trunk with a big breath.
- Drive through your whole foot to stand up, keeping your torso upright and letting the bar slide up the backs of your legs.
- Finish standing tall with your knees straight, shoulders back and the bar resting against the backs of your thighs.
- Squat back down under control, knees tracking over your toes and back flat, until the plates are just above the floor or the bar is just above the blocks.
- After the last rep, set the bar down fully before letting go.
- Flat back, chest up
- Bar close to the backs of your legs
- Push the floor away
- Knees over your toes
- Shoulders back, torso upright
- Arms straight, legs do the lifting
In VALDA, these cues are one tap away on the exercise while you train.
What it trains
| Muscle | Role | Evidence |
|---|---|---|
| Quadriceps: vastus lateralis | Prime mover | C |
| Quadriceps: vastus medialis | Prime mover | C |
| Gluteus maximus | Secondary | C |
| Hamstrings | Secondary | D |
| Erector spinae | Stabiliser | C |
| Forearm flexors | Stabiliser | D |
| Trapezius | Stabiliser | D |
Evidence grades: A = strong research base · B = good · C = limited · D = coaching consensus.
What goes wrong, and the fix
Rounding the back at the start
Fix: Squat down with your chest up and set a flat back before each rep.
Hips rising first
Fix: Drive your knees and hips up together, keeping your torso upright.
Bar drifting away from the legs
Fix: Keep the bar in light contact with the backs of your legs throughout.
Heels lifting
Fix: Keep your whole foot flat and push through the middle of the foot.
Bending the arms
Fix: Keep your arms straight and let your legs do the lifting.
Grip giving out before the legs
Fix: Use lifting straps once your grip, not your legs, ends the set.
What the research says
StrengthMuscle growthEndurance
- Range of motion — A meta-analysis found full-range training built more leg muscle and strength than partial-range training. In the barbell hack squat, depth is set by where the plates meet the floor or blocks.
- Load by goal — Research comparing loads finds maximal strength favours heavier loads, while muscle growth is similar across a wide range of loads when sets are taken close to failure.
- Effort — Studies show sets that finish a few reps short of failure capture most of the growth benefit, and true failure adds only a small extra return.
- Volume — Research links more weekly sets for a muscle to more growth, with diminishing returns. There is no research specific to the barbell hack squat.
- Rest — In trained lifters, rests of about 3 minutes between sets have produced greater strength and size gains than 1-minute rests.
Swap it mid-workout
With VALDA Pro, FLEX offers alternatives like these when you swap an exercise mid-workout.
Log the barbell hack squat in VALDA, with these cues one tap away while you train and your history for it in one place.
General information about exercise technique, not medical advice. If you have an injury or a health condition, your healthcare provider is the right person to ask.