The Hack Squat is a popular exercise used by many weightlifters for lower-body development. It is performed on a sled that allows you to Squat on a 45-degree angle. The three main muscle groups it primarily trains are the quadriceps, hamstrings and glutes.

This machine is a staple in most fitness facilities. And if you’ve seen someone using it, you’ve undoubtedly noticed that they were lifting a ton of plates—certainly a lot more than they use when doing a barbell Squat.

The fact that you can load this up makes it incredibly popular. Who wouldn’t want to do an exercise where they take up half the plates in the gym? It makes the person seem super strong!

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But just because it’s possible to lift heavy weight doesn’t necessarily make the Hack Squat a good exercise. Let’s investigate.

Benefits of the Hack Squat:

• Because the Hack Squat takes the upper body out of the movement, it removes potential weaknesses or compensations that could affect your squat depth. You can focus on getting your thighs to parallel.
• As mentioned above, you can load up the weight—thanks to additional control provided by the machine and the fact that your core is taken out of the movement.
• It’s easy to train one leg at a time to reduce muscle imbalances.
• You can change the focus of the exercise by adjusting your foot position. A higher foot position emphasizes the glutes, whereas a lower foot position emphasizes the quads.
• Due to the stability provided by the machine, it can be a safer way to start building strength when you’re coming back from an injury.

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Cons of the Hack Squat

• You’re forced to work in a fixed angle, which is not how sports are played, so it doesn’t train your body specifically for how you move on the playing field.
• Since you’re locked into a machine, critical stabilizer muscles (which help keep your joints safe) are not engaged.
• During a traditional barbell Squat, your core has to work overtime to help control and stabilize the weight. This important benefit is lost in the Hack Squat.
• Your knees sit far out in front, which can cause knee problems, especially when you use heavy weight loads.

What’s the Verdict?

Weighing the positives and negatives, I don’t recommend that athletes use the Hack Squat in their training programs. Despite the ability to lift extremely heavy loads, its failure to engage the stabilizer muscles and fixed range of motion make this machine more suited for bodybuilders than athletes. Athletes need to train in a free range of motion.

When it comes right down to it, nothing beats free weights. I’d much rather see someone do a 300-pound Back Squat than a 600-pound Hack Squat. Try both and you’ll notice how much harder the Back Squat is.

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Here are a few exercises I recommend instead of the Hack Squat:

• Barbell Back or Front Squats
• Bulgarian Split Squats (front or back barbell placement)
• Dumbbell Curtsy Lunges
• Deadlift
• Barbell Hip Thrust

All of that said, there are instances where the Hack Squat is OK. Specifically, if you’re coming back from an injury, the added stability is extremely valuable. It’s typically used to get the muscles firing again and build a base of strength, and once that’s established, free weight exercises are preferred.