Hack Squat
The Hack Squat is a beginner compound movement that activates 4 muscle groups simultaneously. It primarily targets the Quadriceps, making it one of the more efficient exercises in RepStack's 873-exercise database.
Starting position
Ending position
Muscles Worked
The quadriceps handles the primary load during this movement. The calves and glutes and hamstrings assist as stabilizers throughout the range of motion.
How to Hack Squat
- 1
Place the back of your torso against the back pad of the machine and hook your shoulders under the shoulder pads provided.
- 2
Position your legs in the platform using a shoulder width medium stance with the toes slightly pointed out. Tip: Keep your head up at all times and also maintain the back on the pad at all times.
- 3
Place your arms on the side handles of the machine and disengage the safety bars (which on most designs is done by moving the side handles from a facing front position to a diagonal position).
- 4
Now straighten your legs without locking the knees. This will be your starting position. (Note: For the purposes of this discussion we will use the medium stance described above which targets overall development; however you can choose any of the three stances described in the foot positioning section).
- 5
Begin to slowly lower the unit by bending the knees as you maintain a straight posture with the head up (back on the pad at all times). Continue down until the angle between the upper leg and the calves becomes slightly less than 90-degrees (which is the point in which the upper legs are below parallel to the floor). Inhale as you perform this portion of the movement. Tip: If you performed the exercise correctly, the front of the knees should make an imaginary straight line with the toes that is perpendicular to the front. If your knees are past that imaginary line (if they are past your toes) then you are placing undue stress on the knee and the exercise has been performed incorrectly.
- 6
Begin to raise the unit as you exhale by pushing the floor with mainly with the heel of your foot as you straighten the legs again and go back to the starting position.
- 7
Repeat for the recommended amount of repetitions.
Common Mistakes
- • Brace your core before initiating the movement — maintain tension throughout the entire range of motion.
- • Control the eccentric (lowering) phase for at least 2 seconds to maximize muscle fiber recruitment.
- • Adjust the seat height and pad positions before your working sets — proper alignment prevents joint stress.
- • Avoid locking out aggressively at the top — stop just short of full extension to keep tension on the muscle.
Similar Exercises
Frequently Asked Questions
What muscles does the Hack Squat work?
The Hack Squat primarily works the Quadriceps. Secondary muscles include the Calves, Glutes, Hamstrings, which assist during the movement.
Is the Hack Squat good for beginners?
Yes, the Hack Squat is suitable for beginners. Start with light weight to master the 7-step form before adding load.
What equipment do I need for the Hack Squat?
You need machine to perform the Hack Squat. Most commercial gyms will have this available.
Track your estimated one-rep max over time. Use our 1RM calculator to see where you stand, or let RepStack compute it automatically after every set.
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