Eye-popping quads are gold in the bodybuilding world, and Tom Platz has made sure of that.
But whilst many associate Tom Platz’s thick thighs with squats, if you’re really looking to pack some muscle on your legs, then it’s time to start prioritising hack squats in your leg day workout.
They’re heavy, effective and you’ll look pretty good doing them – all of these are reasons why the hack squat machine is a staple in bodybuilding gyms. If you want to load your quads, lift heavy, and look strong, the hack squat is your exercise.
If you’re ready to get some serious size on your thighs then stay with us as we break down this ultimate quad-builder. Plus, we’ll look at some variations, so even if you don’t have access to a hack squat machine, you can still benefit from this monster leg exercise.
Contents:
What Is A Hack Squat?
Despite the exercise creeping up on our social feeds more frequently, the hack squat is not a new invention. In fact, it’s been around since the early 1900s as a trusted method of building strength, speed, power, and agility [1]. Its creation is credited to weightlifter and wrestler, George Hackenschmidt, who lifted 187lb on his back, with his knees bent. He realized the squat adaptation allowed a heavier weight to be lifted without load on the spine, which became known as the ‘Hack Squat’. Today, the hack squat machine is a staple in most bodybuilding gyms.
As an exercise, the hack squat lies somewhere between a barbell squat and a leg press – the upright body position and weight loading mimicking that of a barbell squat, whilst the stability of the machine mimics the leg press. The hack squat is usually performed on a hack squat machine, where the lifter stands on a plate and the weight rests on their shoulders. The lifter squats down, and then pushes the weight up, driving through their feet.
Hack Squat Muscles Worked
The hack squat engages several lower body muscles, including:
Quads (main target muscle)
Hamstrings
Glutes
Core Engagement During Hack Squat
Whilst core engagement is required to protect the lower spine and back during the movement, it’s important to note that due to support of the upper body from the machine, core muscle activation is lower during the hack squat compared to a barbell squat [3].
A benefit of this is that it allows for heavier loads to be lifted, making the hack squat well suited to those with aesthetic goals (e.g. bodybuilders purely wanting to focus on leg gains).
However, If your overarching goal is performance-based (e.g. building athleticism for a sport), then a free weight squat (barbell or goblet squat) may be more beneficial, providing more challenge for core stability, balance, and muscle coordination – important skills in many sports.
Hack Squat Benefits
The fixed upright position of the hack squat ensures the quads are the main driver on the upward phase of the movement, compared to a back squat, where work is distributed more evenly between the leg muscles. If growing your quads is your goal, then the hack squat is one of the best exercises you can do.
Using a hack squat machine, the position of the body is isolated and the back is supported throughout the movement, making it more stable than a barbell squat. Not only does this make the exercise safer, but a great alternative exercise for those with back pain or stability issues who may not be able to perform a barbell squat [5].
A barbell squat requires good ankle mobility in order to reach full depth whilst allowing the knee to track over the toe, through a movement called dorsiflexion. This can be challenging for some with limited ankle mobility. Hack squats, on the other hand, require less ankle mobility to reach full depth, as the shins stay more perpendicular to the ground, making it easy for those with limited ankle mobility to perform the movement properly and work the muscles through full ROM.
How To Use A Hack Squat Machine
Many gyms have a hack squat machine. This is the simplest way to set up and perform a hack squat:
Load the machine with the desired weight. Adjust the shoulder pads if necessary (they should sit just lower than shoulder height so that you can press the machine up).
Step onto the platform, placing your back against the backrest, and shoulders under the shoulder pads.
Position your feet on the platform, hip-width apart. Take hold of the handles located next to the shoulder pads.
Push through your feet, fully extending your legs. Release the safety pins.
Start the movement: Slowly lower the weight, blending your knees until your thighs are parallel with the floor.
Pause, then reverse the movement, extending your legs and driving through your heels, until you are back to starting position. Ensure your knees do not lock out at the top.
Repeat for the desired number of reps.
Hack Squat Foot Placement
Where you place your feet on the platform can affect muscle activation. Whilst no research has been done specifically into foot placement during the hack squat, studies have examined foot placement during the leg press, which could be applied to the hack squat. They found that placing the feet lower on the platform led to greater quad activation, whereas higher foot placement on the platform activated the glutes more [6]. In terms of stance width, activation was found to be just as effective during both a narrow and wide stance [7].
Experiment with placing your feet lower or higher on the platform depending on if you want to fully focus on quad development, or engage the glutes more.
Hack Squat vs Leg Press
The most obvious difference between the leg press and hack squat is the body position - with the leg press, the lifter leans back or lies down at a 45-degree angle, pushing the weight upwards, whereas, during a hack squat, the weight rests on the lifter’s shoulders.
Other Key Differences Include:
The leg press allows one leg to be worked at a time, evening out muscular imbalances.
Most people can lift more weight during the leg press, allowing for higher muscle loading.
Hack squats are better at targeting quads, whereas the leg press is one of the best exercises for increasing overall leg strength [8].
Hack squat provides better specific training for barbell squats, as the weight is loaded onto the shoulders, rather than at the feet.
Hack Squat vs Squat
The biggest difference between the hack squat and barbell squat is stability. As discussed, the hack squat holds the upper body in a fixed upright position, whereas during a barbell squat, a lot more core activation is required to safely perform the movement [9].
Other Key Differences Include:
Hack squat primarily targets the quads, whereas the back squat recruits several muscle groups involved in the hip, knee, and ankle joints, leading to more overall development in the lower body [10].
Barbell squats are more complex to learn, making hack squats preferable for beginners.
Barbell squats are more fatiguing, often requiring greater recovery time compared to hack squats.
Barbell squats place more stress on the spine, which may be problematic for those with back issues.
Hack Squat vs Reverse Hack Squat
You may have seen the hack squat performed backwards, with the lifter facing the machine. Don’t worry, they aren’t just performing the hack squat totally wrong – this is actually a variation of the regular machine hack squat.
Instead of honing in on quad activation, the reverse hack squat fires up the glutes and hamstrings. With the chest facing the back pad of the hack squat machine, the reverse hack squat gives room for the butt to be pushed back, increasing knee flexion and posterior chain activation.
Other Key Differences Include:
Reverse hack squat requires greater hip flexion, as the hips hinge to lower the weight. During the regular machine hack squat, the knees do more of the work.
The reverse hack squat has better carry over to front squats, due to the anterior loading of the weight (on the front), requiring the body to adjust form and posture similar to how it would during a front squat.
3 Hack Squat Alternatives
Don’t have access to a hack squat machine, but still looking to build your quads? There are still a number of ways you can perform the hack squat without the hack squat machine, so you don’t need to worry about missing out on those gains!
Barbell Hack Squat
Smith Machine Hack Squat
Landmine Hack Squat
1. Barbell Hack Squat
The most common variation of the machine hack squat is the barbell hack squat. The key difference here is that the barbell is placed behind you, and lifted from the floor, rather than the weight resting on the shoulders.
This variation adds an additional challenge of grip strength – the development of which is beneficial for many other movements including deadlifts and barbell rows. Whilst you may not be able to lift as much as you would during a machine hack squat, you should still be able to lift a significant weight during the barbell hack squat to effectively challenge the legs.
How To Perform the Barbell Hack Squat:
Stand with your feet hip-width apart, barbell behind you.
Squat down, taking the bar in an overhand grip (knuckles facing down), hands just outside of legs.
Take a deep breath in, engaging the core. Keeping a flat back and chest up, stand up, driving through the heels.
Pause at the top of the movement, squeezing your quads and glutes.
Reverse the movement, squatting back down to the starting position in a controlled manner.
Tip: Try adding elevating your heels on a plate. This will encourage a deep squat position, firing up the quads even more.
2. Smith Machine Hack Squat
The Smith Machine hack squat is a great alternative to the machine hack squat, with a similar loading (weight rests on shoulders) and a fixed bar path. If you don’t have access to a hack squat but want to focus on training your quads, give the Smith Machine hack squat a go.
How To Do The Smith Machine Hack Squat:
Set the Smith Machine bar to shoulder height.
Approach the bar and rack it on your upper back, placing your hands just outside of the shoulders. (Face in the direction that will allow you to rotate your wrists backwards to unrack the bar. Usually, this is facing outwards, away from the machine.)
Move the bar off the hooks and walk your feet out a couple of steps, so they are in front of the bar. (This is where the Smith Machine hack squat differs from a regular Smith Machine squat). Place your feet hip-width apart, toes facing forward.
Brace your core and squat down until your thighs are parallel to the floor, ensuring the lower back does not round and your knees track in line with your toes.
Pause and then push through your heels to come back up to standing.
Repeat for the prescribed number of reps.
3. Landmine Hack Squat
If you read our previous article on the Landmine Press, you’ll be familiar with the barbell landmine. Once a barbell is attached to the landmine, one side becomes anchored to the floor, whilst the other end is free-moving. This provides enough stability to safely perform a hack squat.
How To Do A Landmine Hack Squat:
Secure the barbell into the landmine attachment. If you wish, load a weight plate onto the free end of the barbell to increase the load.
Clean the barbell up onto one shoulder, then turn 180-degrees so you are facing away from the landmine, holding the end of the barbell with both hands.
Step your feet a couple of steps out in front of you, positioning your feet hip-width apart.
Squat down, pushing your hips back, keeping a flat back, upright chest, and core engaged, until your thighs are parallel to the floor.
Pause and then drive through your feet, straightening your legs until you are back at the starting position.
To ensure safe descent, turn back to face the barbell, before transitioning it from your shoulder, to between your legs, down to the floor.
As the landmine hack squat is asymmetrical (the barbell is placed on one shoulder) it’s important to maintain weight distribution throughout the movement, engaging both shoulders and keeping the torso straight. Alternate sides every set to prevent muscular imbalance.
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If you’re ready to build and define your quads, give the hack squat a go. For ultimate muscle gain, choose one of these exercises and perform 4 sets of 8-12 reps on your next leg day – just don’t blame us if you can’t walk the next day!
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WRITTEN BY: Alex Kirkup-Lee
Alex is an inhouse Content Writer for Gymshark’s Health & Conditioning categories. A qualified Personal Trainer, CrossFit Level 1 and Functional Fitness Coach, Alex is experienced in training clients from a range of sporting backgrounds. With a passion for functional training, her favorite workout is anything that includes deadlifts, rowing, or wallballs.
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References:
Schwarz, N.A. et al. (2019) A comparison of machine versus free-weight squats for the enhancement of lower-body power, speed, and change-of-direction ability during an initial training phase of recreationally-active women, Sports (Basel, Switzerland). Available at: https://pubmed.ncbi.nlm.nih.gov/31574918.
Clark, D.R., Hunter, A.M. and Lambert, M.I. (2019) Trunk muscle activation in the back and hack squat at the same relative loads, Journal of strength and conditioning research. Available at: https://pubmed.ncbi.nlm.nih.gov/28704312/.
Clark, D.R., Hunter, A.M. and Lambert, M.I. (2019) Trunk muscle activation in the back and hack squat at the same relative loads, Journal of strength and conditioning research. Available at: https://pubmed.ncbi.nlm.nih.gov/28704312/.
Erdağ, D. and Ulaş Yavuz, H. (2020) Evaluation of Muscle Activities During Different Squat Variations Using Electromyography Signals, In book: 10th International Conference on Theory and Application of Soft Computing, Computing with Words and Perceptions . Available at: https://www.researchgate.net/publication/337400852_Evaluation_of_Muscle_Activities_During_Different_Squat_Variations_Using_Electromyography_Signals.
Da Silva, E.M. (2008) Analysis of Muscle Activation During Different Leg Press Exercises at Submaximum Effort Levels. Available at: https://journals.lww.com/nsca-jscr/pages/articleviewer.aspx?year=2008&issue=07000&article=00005&type=Fulltex.
Martín-Fuentes , I., Oliva-Lozano, J.M. and Muyor, J.M. (2020) Muscle activation and kinematic analysis during the inclined leg press exercise in young females, International journal of environmental research and public health. Available at: https://pubmed.ncbi.nlm.nih.gov/33238589.
Martín-Fuentes, I., Oliva-Lozano, J.M. and Muyor, J.M. (2020) Evaluation of the lower limb muscles’ electromyographic activity during the leg press exercise and its variants: A systematic review, MDPI. Available at: https://www.mdpi.com/1660-4601/17/13/4626.
Clark, D.R., Hunter, A.M. and Lambert, M.I. (2019) Trunk muscle activation in the back and hack squat at the same relative loads, Journal of strength and conditioning research. Available at: https://pubmed.ncbi.nlm.nih.gov/28704312/.
Gullett, J.C. et al. (2009) A biomechanical comparison of back and front squats in healthy trained individuals, Journal of strength and conditioning research. Available at: https://pubmed.ncbi.nlm.nih.gov/19002072/.
