Is hack squat easier than barbell squat?

For balance, yes: the back pad and fixed sled path remove the need to stabilize a bar, so most people learn it faster and lift more weight on it. A study of ten men found they could lift more on the hack squat than on the back squat, but their trunk muscles worked harder in the back squat at the same relative loads, so the machine does not replace the Barbell Squat for building trunk strength.

Can I do hack squats if I have lower back issues?

Often, as long as you keep your hips and lower back pressed into the pad and stop above the depth where your pelvis tucks under. The shoulder pads still load the spine, so if pain flares up, a Machine Leg Press is a gentler option and a physical therapist can tell you what your back tolerates.

How far down should I go on a hack squat?

Go as deep as you can while your heels stay flat and your lower back stays on the pad, which for most people is at least the point where the knees bend to 90 degrees. Deeper reps are not harmful for healthy knees and work the glutes and adductors through a bigger range.

Where should I put my feet on a hack squat?

Start with your feet about shoulder-width apart in the middle of the platform, toes turned slightly out. Move them lower to bias the quadriceps or higher to bring in more glute work and ease the load on the knees, and keep any placement where your heels stay flat through the whole rep.

Is the hack squat bad for your knees?

No, not for healthy knees worked through a range you control. The knees do travel past the toes, which is normal, but the lower your feet sit the more of the load the knee takes, so people with knee pain often do better with the feet higher and a shorter range at first.

What is the difference between a hack squat and a leg press?

On a hack squat you stand under shoulder pads and move your body with the sled, so it stays close to a squat pattern. On a Machine Leg Press you sit and push a platform away, which takes the load off your shoulders and spine and usually lets you move more weight.

Hack Squat

What Is the Hack Squat?

Hack Squat is a compound exercise that primarily targets the quadriceps and also engages the glutes and adductors. It is a beginner-level movement performed on a plate-loaded sled machine: you stand on an angled foot platform with your back against a padded sled and your shoulders under the shoulder pads, and the sled travels up and down a fixed incline as you squat. The guided path removes the need to balance a load, so you can focus on driving with your legs.

This exercise is commonly used to build lower body strength and size. Because of the fixed trajectory of the hack squat machine, users can lift relatively heavy weights safely, which can lead to effective hypertrophy, especially in the quadriceps. It's also a popular alternative or complement to barbell squats in leg-day routines.

Because the back pad supports your torso, the hack squat asks far less of the trunk and lower back muscles than a free-weight squat, which makes it a common way to add leg volume without the lower back fatigue that heavy barbell squats bring. The load still presses down through the shoulder pads, though, so the spine is not unloaded the way it is on a Machine Leg Press, where you sit and push a platform away.

Foot placement on the platform shifts the work. A lower placement lets the knees travel further forward and puts more of the load on the quadriceps, while a higher placement keeps the shins more upright and takes the hips through a bigger range, so the glutes and adductors do more. The sled machine is a different exercise from the Barbell Hack Squat, where you hold a barbell behind your legs, and from the Machine Pendulum Squat, which swings on an arc. If you cannot yet squat to a comfortable depth, build up with a Bodyweight Squat or a Dumbbell Goblet Squat and keep the sled light.

Muscles Worked

MuscleActivation

Vastus Lateralis: Primary
Vastus Medialis: Primary
Rectus Femoris: High
Adductor Magnus: Medium
Gluteus Maximus: Medium
Biceps Femoris: Low
Semitendinosus: Low
Soleus: Minimal

Instructions

Load the machine, then step onto the platform and press your back and hips flat against the pad with your shoulders under the shoulder pads.
Place your feet about shoulder-width apart in the middle of the platform, toes turned slightly out.
Grip the handles in front of the shoulder pads, straighten your legs to take the weight, and release the safety handles to free the sled.
Brace your core and lower the sled by bending your knees and hips, keeping your knees in line with your toes.
Descend as deep as you can while your heels stay flat and your lower back stays on the pad, at least until your knees bend to about 90 degrees.
Push through your heels to drive the sled back up until your legs are straight, finishing under control rather than snapping the knees back.
Repeat for the desired number of repetitions and re-engage the safety handles once done.

Common Mistakes

Heels lifting off the platform
Rising onto the toes shifts the load onto the front of the knee, so move the feet a little higher or shorten the depth until the heels stay flat.
Letting knees collapse inward
Improper knee tracking can lead to joint strain and long-term injury.
Lower back peeling off the pad
Sinking deeper than your hips and ankles allow tucks the pelvis and rounds the lower back off the pad, loading the spine in a flexed position.
Bouncing out of the bottom
Dropping the sled fast and rebounding takes work off the legs and jolts the knees and lower back where they are most loaded.
Not using full range of motion
Half-reps limit muscle activation and reduce the effectiveness of the exercise.
Slamming the knees into lockout
Snapping the knees straight under a heavy sled jars the joint and takes tension off the quadriceps, so finish each rep under control.

Injuries

Hack Squat is a low risk exercise when performed with proper technique. The back pad, the guided sled path and the safety handles remove most of the balance and bar-control problems that cause trouble in free-weight squats, so the risk comes mainly from loading the knees and lower back in poor positions.

The knees and the lower back are the usual strain points. Letting the knees cave inward as you drive up, or setting the feet so low that the heels lift, piles stress onto the knee joint, while sinking deeper than your hips and ankles allow tucks the pelvis and peels the lower back off the pad, so the spine takes load in a rounded position. Knees traveling past the toes is normal on this machine and is not harmful for healthy knees, but people with sore knees often do better with the feet a little higher on the platform, which keeps the shins more upright.

Keep your heels flat, your hips and lower back against the pad, and your knees tracking in line with your toes, and only go as deep as you can while all three hold. Learn the movement with the empty sled or a light load and add weight gradually. If the machine aggravates your knees or back, a Machine Leg Press or a Bodyweight Box Squat to a comfortable height are gentler starting points. Once the hack squat feels solid, a slower lowering phase, a pause at the bottom or the Barbell Squat add challenge.

Stop the set and re-engage the safety handles if you feel sharp pain in the knee, pain that runs down the leg, or pinching in the hip or lower back. Pain that lingers after training is a reason to see a physical therapist or doctor before loading the movement again.

Overview

Primary Focus: Quads
Equipment: Machine
Modality: Strength
Difficulty: Beginner

Alternative Exercises

Other Names for the Hack Squat

The Hack Squat is also known as:

Machine Hack Squat

Frequently Asked Questions

Q: Is hack squat easier than barbell squat?: For balance, yes: the back pad and fixed sled path remove the need to stabilize a bar, so most people learn it faster and lift more weight on it. A study of ten men found they could lift more on the hack squat than on the back squat, but their trunk muscles worked harder in the back squat at the same relative loads, so the machine does not replace the Barbell Squat for building trunk strength.
Q: Can I do hack squats if I have lower back issues?: Often, as long as you keep your hips and lower back pressed into the pad and stop above the depth where your pelvis tucks under. The shoulder pads still load the spine, so if pain flares up, a Machine Leg Press is a gentler option and a physical therapist can tell you what your back tolerates.
Q: How far down should I go on a hack squat?: Go as deep as you can while your heels stay flat and your lower back stays on the pad, which for most people is at least the point where the knees bend to 90 degrees. Deeper reps are not harmful for healthy knees and work the glutes and adductors through a bigger range.
Q: Where should I put my feet on a hack squat?: Start with your feet about shoulder-width apart in the middle of the platform, toes turned slightly out. Move them lower to bias the quadriceps or higher to bring in more glute work and ease the load on the knees, and keep any placement where your heels stay flat through the whole rep.
Q: Is the hack squat bad for your knees?: No, not for healthy knees worked through a range you control. The knees do travel past the toes, which is normal, but the lower your feet sit the more of the load the knee takes, so people with knee pain often do better with the feet higher and a shorter range at first.
Q: What is the difference between a hack squat and a leg press?: On a hack squat you stand under shoulder pads and move your body with the sled, so it stays close to a squat pattern. On a Machine Leg Press you sit and push a platform away, which takes the load off your shoulders and spine and usually lets you move more weight.