How to Do It
- Set your back and shoulders firmly against the pads and place your feet on the platform where the whole foot can stay in contact.
- Choose a stance that lets your knees track over your toes, then practice an unloaded repetition to check the machine's range.
- Check and release the stops according to the machine's instructions, keeping your hands on the handles.
- Descend under control while maintaining back, shoulder, heel, and pelvis contact with the supports.
- Press through the whole foot to stand, then re-engage the stops as directed before stepping out.
Technique
- Machine geometry and limb proportions determine the useful foot position; avoid universal stance or depth prescriptions.
- The machine path supplies support and changes trunk demands compared with a free-weight back squat.
- Log the machine model and settings before comparing performance between sessions.
Key Cues
- Back and shoulders supported.
- Heels down.
- Knees track over toes.
- Use the stops as instructed.
Common Mistakes
- Placing the feet too low for the available ankle motion and allowing the heels to lift.
- Letting the knees collapse inward or bouncing from the bottom.
- Allowing the pelvis or back to lift away from the pads.
- Cutting every repetition short or forcing a depth the machine and body cannot control.
- Treating hack-squat and barbell-squat kilograms as equivalent.
To use a hack squat machine, place your back and shoulders firmly against the pads, set your feet where you can keep heels down, release the stops, descend with knees tracking over the toes, and stand by pressing through the whole foot. Use a depth you can control without the pelvis lifting or the knees collapsing inward.
This page covers the machine hack squat. It does not target the barbell-behind-the-legs lift that is sometimes given the same name; that is a different movement and would need its own page.
Setup Checklist
| Check | What to look for |
|---|---|
| Back and shoulders | Firm, consistent contact with the pads. |
| Feet | Whole foot supported; stance allows knees to track over toes. |
| Stance | Comfortable enough to control the descent without the heels lifting. |
| Stops | Checked and used according to the machine’s instructions. |
| Practice rep | An unloaded repetition confirms the available range before adding plates. |
Muscles Worked by the Hack Squat
The machine hack squat mainly trains the quadriceps and glutes, with the adductors assisting. The guided path and pads reduce balance requirements compared with a back squat, but that does not make either exercise universally better. Visit the quadriceps and glutes hubs for related exercise options.
Foot Placement and Depth
Start around shoulder width with the whole foot supported. Make small adjustments for your anatomy and the particular machine, then use the deepest range you can control while keeping your heels, back, shoulders, and pelvis supported. Avoid claims that one foot position isolates the quads or glutes.
Hack Squat vs Leg Press vs Back Squat
| Exercise | Guided path | Trunk support | Best fit | Main limitation |
|---|---|---|---|---|
| Hack squat | Yes | Back/shoulder pads | Supported squat-pattern quad work | Machine availability and geometry |
| Leg press | Yes | Seat/back pad | Heavy lower-body work with minimal balance | Less squat-specific movement and variable designs |
| Back squat | No | None | Free-weight squat skill and whole-body bracing | Higher coordination and setup demand |
| Goblet squat | No | None | Learning squat depth and control | Load becomes limiting as strength rises |
In a small laboratory study of ten men, back squats produced greater trunk-muscle activation than machine hack squats at matched relative loads, even though absolute hack-squat loads were higher. This supports a distinction in trunk demand; it does not prove that either exercise is universally better for leg growth or safety.
Sets, Reps, and Progression
Use the sidebar ranges as a starting point. Add repetitions first, then load, while preserving pad contact and the machine’s range. Log the machine model, stops, seat settings, stance, and load because machine numbers are not directly comparable.
Alternatives and Regressions
- Leg press: a supported machine alternative with a different path.
- Back squat: a free-weight squat skill and bracing option.
- Goblet squat: a simple way to practice squat control.
- Bulgarian split squat: a unilateral lower-body alternative.
- Leg extension: a direct quadriceps accessory.
- Build the movement into a structured leg day workout when the supported squat pattern fits your goal.
Evidence and Editorial Scope
The trunk-activation comparison was acute and used ten men; it does not establish long-term hypertrophy or injury outcomes. This page does not claim that hack squats are safer than back squats and does not provide pain, rehabilitation, or diagnostic advice. See the exercise methodology for how evidence and limits are handled.
Alternatives
- Leg Press: A supported lower-body machine with a different body position and path.
- Barbell Back Squat: A free-weight squat pattern with higher balance and trunk demands.
- Goblet Squat: A simpler front-loaded squat for learning control.
- Bulgarian Split Squat: A unilateral alternative for lower-body training.
- Leg Extension: A supported single-joint quadriceps accessory.
References
- Anaerobic and Muscle Endurance Development: Lifting Guidelines. National Strength and Conditioning Association (2017)Back to claim
- American College of Sports Medicine Position Stand. Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults: An Overview of Reviews. Medicine & Science in Sports & Exercise (2026)Back to claim
- Updating ACSM's Recommendations for Exercise Preparticipation Health Screening. Medicine & Science in Sports & Exercise (2015)Back to claim
- Trunk Muscle Activation in the Back and Hack Squat at the Same Relative Loads. Journal of Strength and Conditioning Research (2019)Back to claim
- American College of Sports Medicine Position Stand. Resistance Training Prescription for Muscle Function, Hypertrophy, and Physical Performance in Healthy Adults: An Overview of Reviews. Medicine & Science in Sports & Exercise (2026)Back to claim
See our exercise methodology for how this evidence is applied and its limits.
Frequently Asked Questions
- What muscles does the hack squat work?
- The machine hack squat mainly trains the quadriceps and glutes, with the adductors assisting. The supported path reduces balance requirements, while the exact emphasis varies with machine geometry, stance, and depth.
- Is the hack squat the same as a leg press?
- No. Both use guided machines, but the hack squat places the torso on an angled carriage and follows a squat-like path, while the leg press has the user push a platform away from a seated or reclined position.
- Is a hack squat better than a back squat?
- Neither is universally better. A back squat demands more trunk stabilization and free-weight skill; a hack squat supplies support that can make focused lower-body work easier. Choose based on the adaptation the program needs.
- Where should your feet be on a hack squat?
- Start around shoulder width with the whole foot in contact and adjust enough to let the knees track over the toes without the heels or pelvis lifting. Avoid rigid universal placement rules because machine designs and limb proportions differ.
- How deep should you hack squat?
- Descend through the deepest controlled range that keeps the heels down, knees tracking, and pelvis and back supported. Do not force a prescribed depth if those positions change or discomfort appears.
- Why can I hack squat more than I back squat?
- The machine supports the trunk and constrains the path, and machine leverage changes the external load. A small study found higher hack-squat loads alongside lower trunk activation, so the numbers should not be treated as equivalent lifts.