Quick takeaways: hack squats are quad-dominant but train the whole lower body. Use stance and foot placement to bias quads vs. glutes. Control depth, keep the pelvis and spine neutral, and progress load over time.
Introduction to Hack Squats
The hack squat is a compound lower-body exercise most often performed on a sled-style machine with back support and shoulder pads. It primarily targets the quadriceps while engaging the glutes and hamstrings, with the core stabilizing the torso. Because the machine constrains the path, it’s a popular choice for building leg size and strength with a lower technical barrier than barbell squats.
Benefits of the Hack Squat Machine
- Safer load path and back support reduce shear on the spine compared with some free-weight variations, especially at higher reps.
- Easy to bias target muscles by changing stance and foot position.
- Allows deep, repeatable range of motion to load quads through knee flexion.
- Useful for hypertrophy blocks due to stable setup and simpler bracing.
- Great for beginners learning squat mechanics and for advanced lifters chasing quad volume without taxing the lower back.
How to Set Up the Machine
- Adjust shoulder pads so they sit firmly without compressing the neck.
- Set back pad height to keep your hips centered on the sled.
- Place feet on the platform shoulder-width apart, toes slightly out (5–15 degrees).
- Set safeties at, or just below, your intended depth.
- Start with a weight you can control for 10–12 reps before progressing.
Form and Technique (step-by-step)
- Unrack and brace: stand tall under the pads, ribs down, pelvis neutral. Inhale through the nose, expand the torso 360 degrees, lightly tuck the pelvis to avoid over-arching.
- Descent: sit “between” your ankles, keeping heels flat. Let the knees track over the toes; avoid letting them cave in. Maintain contact between low back and pad without posteriorly tilting (butt wink) at the bottom.
- Depth: aim for at least thighs parallel to the platform if mobility allows. Deeper ranges increase quad stimulus provided heels stay down and spine stays neutral.
- Ascent: initiate by driving through mid-foot to heel, pushing the platform away. Exhale through the sticking point, keep the knees tracking, and finish with quads and glutes without locking the knees aggressively.
- Tempo and control: 2–3 seconds down, brief pause near the bottom, 1–2 seconds up. Avoid bouncing.
Foot Placement to Target Different Muscles
- Quad bias: feet lower on the platform, closer stance (hip to shoulder width), slightly more forward knee travel. Keep heels firmly down.
- Glute/ham bias: feet higher and slightly wider on the platform, sit back more to increase hip flexion.
- Vastus medialis (inner quad) emphasis: heels slightly elevated (small wedge or built-in platform tilt), toes modestly out, full controlled depth.
- Adductors: wider stance with toes out a bit more, maintain knee tracking over mid-foot.
Hack Squat Variations
- Machine hack squat: most stable, best for volume and progressive overload.
- Barbell hack squat (behind-the-back deadlift): bar behind legs, pulls quads hard; good free-weight alternative but requires ankle mobility and careful bar path.
- Heel-elevated hack squat: wedge or weight plates under heels to increase knee flexion and quad focus.
- Tempo or pause hack squats: 3–4 seconds down or 1–2 second pause at the bottom for more tension with lighter loads.
- Single-leg (staggered or true unilateral): reduces side-to-side imbalances and increases glute/quad stimulus per leg.
Comparison to Other Lower-Body Exercises
- Leg press: similar stability, often allows more load, but hack squat typically demands more knee flexion and can hit quads harder at comparable ROM.
- Leg extension: isolates quads well but lacks multi-joint loading; pair with hack squats for complete quad development.
- Back/front squat: require more whole-body stability and skill; front squats share a strong quad bias. Many lifters rotate barbell squats and hack squats across the week.
Programming the Best Hack Squat Workout
Choose one of these templates based on your goal. Rest 2–3 minutes between hard sets; 90–120 seconds for lighter, higher-rep work.
Muscle gain (hypertrophy, quads focus)
- Hack squat: 3–4 sets of 6–10 reps at RPE 7–9, 2–3 second eccentric
- Romanian deadlift or hip hinge: 3 x 6–10
- Leg press (heel-elevated or neutral): 2–3 x 10–15
- Leg extension (pause at top): 2–3 x 12–15
- Optional finisher: walking lunges 2 x 12–16 steps
Strength (with carryover to squats)
- Hack squat: 5 x 3–5 reps at RPE 7–8, longer rest, crisp technique
- Front squat or safety-bar squat: 3 x 3–5
- Hamstring accessory (RDL, ham curl): 3 x 6–10
- Calves: 3 x 8–12
Glutes/hamstrings emphasis
- High-feet, wider-stance hack squat: 4 x 8–12
- Romanian deadlift: 3 x 6–10
- Hip thrust or glute bridge: 3 x 8–12 (2-second peak squeeze)
- Abduction machine or cable: 2–3 x 12–15
Beginner progression (8–10 weeks)
Weeks 1–2: 3 x 10–12 with very light load to groove depth and control
Weeks 3–4: 3 x 8–10, add small load each session
Weeks 5–6: 4 x 8, add a pause near bottom on first 2 sets
Weeks 7–8: 4 x 6–8, increase load if reps stay crisp and knees track well
Deload if knee discomfort or form degrades; drop volume 30–40% for one week.
Common Mistakes and Fixes
- Heels lifting: move feet slightly higher, lighten load, or elevate heels with a wedge while maintaining full-foot pressure.
- Knees collapsing inward: cue “press knees over middle toes,” reduce load, add banded terminal knee extensions or split squats to strengthen.
- Lumbar rounding or over-arching: keep ribs down, light posterior pelvic tilt at setup, brace 360 degrees; don’t chase depth at the expense of spinal position.
- Half-reps for ego: reduce load and standardize depth to at least parallel for consistent hypertrophy stimulus.
Warm-Up and Mobility
- 5 minutes light bike or brisk walk
- Dynamic prep: quad/hip flexor openers, ankle rocks, bodyweight squat with 2–3 second bottom holds
- Specific warm-up sets: 2–3 ramp-up sets on the hack squat, increasing load while reducing reps (e.g., 12, 8, 5) before working sets
Progression and Load Management
- Add 2.5–5 kg (5–10 lb) weekly if you hit top-end reps with clean form.
- Or use double progression: pick a rep range (8–12). When all working sets reach 12 with good form, increase load and repeat.
- Track tempo and depth so progression is apples-to-apples.
Knees and Back Comfort Tips
- Keep shins and thighs warm; sleeves optional for feedback.
- If knees ache at deep angles, try slightly higher foot position, narrower stance, or reduce ROM temporarily while strengthening quads with slow eccentrics.
- For sensitive lower backs, avoid over-arching into the pad; brace and keep pelvis neutral.
Sample 2-Day Lower Body Split Featuring Hack Squats
Day 1 (quad focus):
hack squat 4 x 6–10, walking lunges 3 x 10–12 steps, leg press 2 x 12–15, leg extensions 2 x 12–15, standing calves 3 x 8–12
Day 2 (hinge/glute focus):
RDL 4 x 6–8, high-feet hack squat 3 x 8–12, hip thrust 3 x 8–12, hamstring curl 2–3 x 10–14, seated calves 3 x 10–15
Safety Notes
- Always set safeties before heavy sets.
- Don’t lock knees hard at the top—finish strong but keep a soft lock.
- If you feel sharp pain (knee joint, hip pinch, spinal pain), stop and reassess stance, ROM, and load.
Want this adapted to your equipment, current numbers, and schedule? Share your 5RM or 10RM on hack squats, any knee/back constraints, and how many days per week you can train, and I’ll tailor a week-by-week plan.
