Quad Goals: Mastering the Hack Squat

If you're in the mood to blast your quads, the barbell hack squat exercise is hard to beat. Popularized by pioneer of modern physical culture, George Hackenschmidt (hence the name), the barbell is placed behind your legs, which keeps loading off of your spine while still giving your quads a run for their money.

If you're a lifter who wants to strengthen or grow your quads, or want some variety on leg day, especially if you don't have access to a hack squat machine, barbell hack squats are worth a try. Here's how to do them.

How to Do the Barbell Hack Squat

Depending on your anatomy, your hack squat form can vary. If you find the bar hits your hamstrings, you'll need to rock forward slightly (with control), which can put even more nasty (good nasty) tension on your quads. You can also try using a heel wedge to get a better angle and blast your quads even more.

If you're on the search for the perfect bar to support hack squats, check our our write up detailing different barbells for different types of lifting.

How to Barbell Hack Squat with Perfect Form:

• Stand with feet hip- to shoulder-width apart, barbell resting behind your heels.
• Grip the barbell with an overhand grip, palms facing backward.
• Keep chest up, core braced, and drive through your feet to stand tall, keeping the barbell close to your body. You may need to rock slightly forward to clear the bar past your hamstrings.
• Lower the bar with control by hinging slightly at the hips and bending knees.
• Keep your spine neutral throughout the lift, no rounding.

Hack Squat Muscles Worked and Benefits

The primary muscle group worked by the hack squat is the quadriceps (vastus medialis, lateralis, rectus femoris), and the secondary muscles worked include the glutes, hamstrings, erector spinae, calves, and core stabilizers.

According to EMG research, hack squats show lower spinal and hamstring activation than other squat types, which means less stress on the back. If you want to prioritize spine and knee stability, hack squats are a great alternative to front squats for the quads.

Though back squats will activate your core and glutes more than hack squats, that doesn't necessarily give them a win. When it comes to building muscle or targeted strength, being able to hit your intended muscle group (in this case, quads), without your core or another muscle group getting tired first, is key.

Since hack squats recruit less glute and erector spinae activity, there's less shear force on the spine, which is ideal for a couple of reasons. One being, if you have back issues or feel limited by your core during back or front squats, hack squats are an ideal way to really hone in on your quads to make them a limiting factor, which will mean better muscle targeting and bigger growth. 

Second, one of the key barbell hack squat benefits is that you don't need to place a barbell across your shoulders. This reduces axial fatigue, which means less systemic/overall fatigue, more energy for other lifts, and an easier recovery. Managing fatigue is key for performance and muscle growth. 

Hack Squat Common Mistakes

Here are some of the most common hack squat form mistakes and how to fix them.

Letting Heels Lift

Similar to a pistol squat, if your heels lift, you'll lose a stable support base, shifting load to your forefoot or toes, and cutting off the ability to engage your quads. If this happens, it can mean your ankle dorsiflexion is limited or your balance and posture are being challenged too much. You might start to compensate by leaning forward or back, which leads to incorrect form and increased risk of strain or injury. 

Fix this form mistake by monitoring your hack squat foot placement to ensure proper technique. If your stance is too narrow or your feet too far forward or backward relative to the bar path, it can cause heel lift. Make adjustments to your foot position to take the pressure off your ankles.

Focus on pushing your weight through your entire foot, especially your midfoot and heels. You can also place small plates or heel wedges under your heels to reduce demand on dorsiflexion. Start with lighter weight until you're more comfortable.

Rounding Your Back During the Pull

Rounding your spine (particularly lumbar flexion) under load is generally risky, since it transfers load unevenly across vertebral discs and ligaments, which can lead to strain or injury. If you catch yourself rounding, it likely means your spine isn't able to keep stable due to core or erector strength.

Aim to keep your trunk upright so your quads can take over instead of relying on your back. Before you lift, brace your core (as if prepping to be punched in the gut), and lift your chest. Keep the load lighter to avoid rounding and especially watch the eccentric (lowering) phase to make sure you stay in control. Consider working on your thoracic spine mobility, too, since a stiff mid back can cause your lower back to pick up the slack.

Placing the Bar Too Far from Your Legs

When the bar is too far from your legs, it puts more demand on your knees, hips, and lower back because you’re fighting a bigger lever. It also means you'll have to reach around more due to the bar path which increases the chances of smacking the bar into your hamstrings or glutes or having the bar drift away.

Keep the bar as close to your body as possible, pulling it toward your calves/legs. Adjust your foot position so that when you rise, the bar doesn't have to swing to clear your body. You might need to lean forward a bit to keep the bar from stalling. Lower the weight and keep your knees over your laces and your hips under your torso.

Hack Squat Variations and Alternatives

If you can't quite get barbell hack squats to work for you, or just want to mix up your leg training, there are several ways to recreate the same movement pattern to hit your quads. 

Hack Squat Machine

A hack squat machine supports your back against a sled at a 45-degree angle. Its stable, controlled path lets you load heavy and isolate the quads with minimal back strain.

How to do it:

• Step onto the platform, shoulders under the pads, feet shoulder-width apart.
• Unlock the safety bars and lower until your thighs are roughly parallel to the platform.
• Drive through your heels to return to the start.

Heels-Elevated Hack Squat

Raising your heels shifts the load forward and increases knee flexion for deeper quad engagement. This version targets the vastus medialis and is ideal if you have limited ankle mobility but still want to reach full depth.

How to do it:

• Place small wedges or weight plates under your heels.
• Perform the barbell hack squat as usual, keeping your torso upright.

Sumo Deadlift (Barbell Hack Squat Alternative)

The sumo deadlift is a wide-stance deadlift that mimics the upright torso and quad emphasis of a hack squat. It builds the quads and adductors while reinforcing hip strength and balance under load.

How to do it:

• Stand with feet wide, toes out. Brace your core, roll your shoulders back and lock them in place.
• Grip the bar inside your knees, keep your chest tall, and drive through the floor.
• Lock out, and slowly lower the bar with control.

Landmine Hack Squat

The landmine hack squat is a home-gym-friendly move that offers a similar forward-angled load to the hack squat. It encourages a natural squat path and strong quad activation without loading the spine.

How to do it:

• Anchor one end of a barbell in a landmine or corner.
• Hold the free end and flip the bar over your shoulder as you turn 180-degrees to face away from the bar.
• Squat down, keeping your torso upright and core braced.
• Push through your feet to explosively rise up to standing.

Smith Machine Hack Squat

This smith machine hack squat variation replicates the barbell hack squat with added stability. The machine keeps the movement pattern consistent while removing balance demands, so it's easier to focus on form and tension. There are two common variations of this movement — one with the bar gripped low and behind you, and the other with your feet extended further out in a back squat setup — we'll detail how to do the back loaded hack squat variation below.

How to do it:

• Stand with the Smith bar set behind your shoulders and feet set a step forward.
• Unrack the bar and lower into a squat, keeping your back straight.
• Lower down until your thighs are a hair beyond parallel with the floor, making sure to keep your knees behind your toes (adjust your feet out further after your rep if needed).
• Then push through your heels to stand tall.
  

[Read More: REP’s Smith Machine Squat Guide]

Hack Squat Workout Reps & Sets

Here are two solid ways to program hack squats depending on your goal:

Hypertrophy Focus

• Sets × Reps: 3-4 sets of 8-12 reps (aim to stop around 1-2 reps in reserve)

• Rest: 90-120 seconds between sets

• Progression: Gradually increase load, even if only by 1-2.5 kg (or 5 lb) when you can hit full reps with clean form

• Tempo / Intensity: Use a controlled descent ( 2-3 seconds) and avoid bouncing at the bottom, maintaining tension the whole way
  
  

Strength Focus

• Sets × Reps: 4-5 sets of 5-6 reps at approx. 80-85% 1RM

• Rest: 2-3 minutes between sets

• Progression: Add load when you can complete all sets / reps with solid form

• Focus: Prioritize form and explosive concentric drive and avoid compromising depth just to hit the numbers
  
  

Programming Tips

We tapped Rosie Borchert, NASM-CPT, for tips to building a balanced lower body workout with a hack squat in the mix:

• Start your session with a warm-up that helps prime your body for the work to come — some light cardio, low weight goblet squats, and dynamic stretching like leg swings.

• Program hack squats with Bulgarian split squats or split squats to keep the focus on your quads but add in some unilateral and stability work.

• You’ve targeted your quads, now add in some work to hit your hamstrings and glutes — an RDL, lying leg curl, and/or a glute bridge to round out your work.

Takeaway

The hack squat lets you zero in on quads while reducing spinal stress. It’s a great accessory lift for anyone building a home gym or looking to switch it up from traditional squats. Play around with your foot position and technique to find a variation that works for your anatomy and mobility. And remember, it's better to go lighter with excellent form than to strain something out of pride.

FAQs

What is a hack squat and what are they good for?

A hack squat is a variation of your typical squat, using a hack squat machine or a barbell set behind you. Hack squats isolate the quadriceps in a knee-dominant movement, which helps you to build size and strength with less lower-back strain. They're also ideal for minimizing fatigue when training quads without having to rely on a leg extension machine.

Is a hack squat better than a barbell back squat?

In the battle of hack squat vs barbell squat, there's no real winner since there’s no universal “better” squat. Hack squats emphasize quads and stability, while back squats recruit more glutes and spinal erectors. Use both or either, based on your goals and limitations.

Can you do a hack squat without a machine?

You can do a hack squat without a machine by using a barbell, landmine, or Smith machine. All let you perform hack-style squats without needing a dedicated machine. After all, the original hack squat was created using a barbell well before these machines existed.

Are hack squats better than leg press?

Hack squats, leg press, sometimes these two machines in the gym can easily get mistaken for one another. However, there are some key differences to these exercises. Hack squats let you access deeper knee flexion and keep a more upright posture, which makes them better for isolating your quads. Leg press machines let you use heavier loads but reduce engagement of stabilizer muscles. So, there isn't one winner in the hack squat vs leg press show down. They're both solid options you can use to work your quads during different training phases.

Rachel MacPherson is a Certified Strength and Conditioning Specialist, Certified Personal Trainer, Nutrition Coach, and health writer with over a decade of experience helping people build strength and confidence through evidence-based training.

This article was reviewed by Rosie Borchert, NASM-CPT, for accuracy.