Smith Machine Squat: Benefits, Muscles Worked, and More

Out of the many machine-based leg exercises, there are few as debated yet accessible as the smith machine squat.

But before including this unique compound movement into your workout, it’s important to understand proper technique and how best to take advantage of its many benefits.

To put it short, the smith machine squat is simply a variation of the squat movement performed with the use of a smith machine. 

The lifter traditionally begins in a standing position with the bar atop their back, before lowering their pelvis and bending at the legs. This is done to build strength and mass in the muscles of the lower body.

What is the Smith Machine Squat?

In more technical terms, the smith machine squat is a multi-joint compound exercise where the majority of resistance is derived from the machine itself. 

The exercise involves mechanics like knee flexion, ankle flexion and hip articulation, and is primarily performed for the purposes of building up lower body muscle mass and strength.

Because the smith machine involves the bar moving solely within a predetermined vertical path, many weightlifting coaches and physicians caution the use of the smith machine for squatting, as it may require an unnatural movement pattern that is distinctly different from that of the free weight squat.

In truth, the smith machine squat is only unsafe if performed incorrectly.

It is important for lifters to understand that it is not the same exercise as the conventional back squat, and that the smith machine squat should be treated as such.

Who Should Do Smith Machine Squats?

Smith machine squats are somewhat more technical than other squat variations, and as such are better left for lifters of at least an intermediate level of training experience.

In particular, bodybuilders with above-average lower body mobility can benefit the most from smith machine squats, as they provide a greater capacity for volume than with free weight squats, and an even further emphasis on the quadriceps.

How to Program Smith Machine Squats

Smith machine squats are comparatively intense and allow for significantly more loading than most other leg exercises. 

This means that they are used either as the primary compound exercise in a leg workout, or as a secondary compound exercise to help boost training volume within the training program.

For lifters new to smith machine squats, a good starting point is 2-3 sets of 8-12 repetitions at a moderate level of resistance.

How to do Smith Machine Squats

To perform a repetition of smith machine squats, the lifter will stand upright within the smith machine, bar held against their trapezius muscle and their hands gripping the bar on both sides.

The legs should be set wider than hip-width apart, with the feet somewhat ahead of the body and pointing forwards. 

It is this latter cue that is especially important, as standard squat advice is to point the feet and knees slightly outward in order to prevent internal rotation, as well as to keep them vertically parallel with the barbell itself. 

This is not the case with smith machine squats, and doing so can pull the pelvis, knees and spine out into a potentially disadvantageous position.

Disengaging the bar safety hooks by rolling it backwards, the lifter will bend at the knees and hips, stopping once the upper legs are horizontally parallel with the ground.

From this point, the lifter will push through their feet and rise back to their original standing position in a slow and controlled manner - thereby completing the repetition.

What Muscles are Worked by Smith Machine Squats?

Smith machine squats are a compound exercise, and as such recruit more than a single muscle group at the same time. 

These muscles are divided by their role within the exercise, with those responsible for the majority of force being dubbed the “primary” mover muscles, and other muscles supporting them being called the “secondary” mover muscles and stabilizers.

Primary Mover Muscles

Smith machine squats work the quadriceps femoris, gluteal muscles and hamstrings to great effect - but it is the quads that receive the greatest benefit, as the placement of the legs ahead of the body will require greater recruitment in order to initiate knee extension.

Secondary Mover Muscles and Stabilizers

In terms of secondary mover muscles, smith machine squats primarily work the calves due to the greater usage of ankle flexion during the exercise. 

In addition, other muscles like the erector spinae, hip flexors and other muscles in the core will be used as stabilizers - albeit to a far lesser degree than with free weight exercises.

What are the Benefits of Doing Smith Machine Squats?

Apart from the sort of benefits one would achieve from any kind of exercise, the smith machine squat is also used for producing several more specific effects useful for the purposes of rehabilitation or bodybuilding.

Excellent for Building the Quadriceps

Because the quadriceps femoris are directly responsible for extension of the knee joints, the exaggerated leg position that is characteristic of the smith machine squat will result in greater emphasis being placed therein.

While the smith machine squat is unlikely to rival exercises like the back squat or lunge in terms of pure activation, lifters may wish to choose the former as an alternative to exercises of a similar intensity instead.

Built-in Smith Machine Safety Mechanisms

Unlike many other heavy compound exercises, the smith machine squat has the added benefit of being technically safer as a result of the mechanisms built into the smith machine itself.

Not only does the smith machine feature a hook that ensures the bar remains racked before each set, but the bar itself will only travel within a specific vertical path - meaning it cannot slip from the lifter’s grip or otherwise tip to one side if the lifter’s balance is failing.

In addition, many smith machine brands have included adjustable safety bumpers that prevent the bar from crushing the lifter in the event that they cannot complete a repetition, further improving the safety of the exercise.

Reduced Stabilizer Muscle Recruitment

Though developing the isometric capacity of any muscle is important for locomotion, a common limiting factor in compound exercises is the premature fatigue of secondary muscles; This can lead to sub-optimized training stimulus and poor form.

Fortunately, the smith machine squat is self-stabilizing in nature, and as such does not require as much effort from stabilizer muscles as other squat variations would. 

Over the course of multiple sets, this means that greater emphasis (and thereby development) may be placed on the primary mover muscles of the quadriceps and posterior chain.

Allows for Greater Weight Loading

Because less effort is being directed towards isometrically recruiting the stabilizer muscles of the movement, the primary mover muscles may function at a greater capacity and therefore bear a heavier amount of weight.

This allows lifters to move more weight than they would with a free weight squat, making the smith machine squat excellent for adapting the lifter to moving heavy amounts of weight.

As a side note, it is vitally important to only perform heavy smith machine squats if you are already familiar with the correct exercise form, and possess sufficient mobility to perform the movement correctly.

Greater Capacity for Volume

Just as how greater loading is possible due to the reduced involvement of secondary muscle groups, so too does the same aspect of the smith machine squat benefit total training volume.

As less energy is diverted towards stabilizer muscles, the lifter will find that they are capable of performing sets with a greater amount of volume than they would with free weight exercises - allowing for greater hypertrophy and endurance adaptations of the lower body.

Common Mistakes Made When Doing Smith Machine Squats

While proper form adherence is important in all exercises, it is especially so with the smith machine squat due to the rather disadvantageous stance involved. 

The following are some of the most common (and important) mistakes to avoid when doing smith machine squats.

Placing the Feet Below the Bar

Lifters familiar with the conventional squat may automatically assume that smith machine squats involve a similar stance. However, this cannot be further from the truth, and performing the smith machine squat in the same manner as a free weight squat can easily lead to injury.

One of the most important examples of this distinction is in the placement of the feet; smith machine squats are not meant to be performed with the feet placed below the torso or the bar. 

Instead, they should be placed several inches ahead of the lifter, just far enough to prevent disadvantageous positioning of the pelvis and spine, but close enough to maintain balance and prevent knee valgus from occurring.

Pointing the Feet Outwards

Though general squat advice says that pointing the feet outward prevents knee valgus and a host of other issues, the fact that the smith machine squat requires the feet to be planted further forwards from the pelvis means that doing so can cause the knees to track incorrectly.

When performing smith machine squats, it is best to keep the toes (and knees) pointing forwards.

Not only does this help diffuse force through the lower body, but it also allows for an easier time maintaining proper form.

“High-Bar” Smith Machine Squat

Because the legs are not vertically parallel with the bar, placing them in a high-bar position can make disengaging the safety hooks difficult and potentially lead to a loss of balance during the start of each repetition.

Instead, place the smith machine’s barbell along the rear of the shoulders, or what is otherwise known as a low bar position.

Curvature of the Upper Back

Just as is the case with other squat variations, allowing the chest and shoulders to cave forward can cause the rest of the spine to be pulled out of neutral curvature. This often results in strain and injury, not to mention a generally poor execution of the smith machine squat.

Throughout the exercise, the lifter should strive to keep the torso upright and the chest pushed forwards. This is further supported by bracing the abdominal muscles, of which help stabilize the torso and keep the rest of the spine at a neutral angle.

Smith Machine Squat Variations and Alternatives

In the event that the smith machine squat doesn’t quite meet your training needs, replacing it with a variation or alternatives may be exactly what is needed.

1. Smith Machine Leg Press

One reason lifters may perform the smith machine squat is if they do not have access to a leg press machine - fortunately, it is entirely possible to replicate the movement in a manner that is more effective than with a simple smith machine squat.

The smith machine leg press will involve the lifter lying on their back and pressing the bar upwards with their feet, and is not only more similar to the leg press in mechanics, but also safer in general.

2. Smith Machine Front Squats

For even greater quadriceps recruitment, the smith machine front squat is an excellent variation to pick.

Not only will the front squat variation provide greater emphasis on the quadriceps muscles, but it will also create a more exaggerated movement by forcing the lifter to place the legs even further forward in comparison to the back squat variation.

3. Conventional Leg Press Machine

One excellent alternative to the smith machine squat is the leg press - both are machine based leg exercises that feature significant amounts of weight and full recruitment of the lower body’s musculature.

Unlike the smith machine squat, the leg press will feature a more natural stance and allows for even further amounts of weight to be loaded - making them particularly useful for strength athletes.

Frequently Asked Questions (FAQ)

How Much Are You Really Squatting on the Smith Machine?

It is difficult to say how much of the weight is actually being moved during a smith machine squat, and attempting to compare it to a free weight squat is entirely the wrong approach.

Smith machine squats not only involve a drastically different stance from most other squat exercises, but they also recruit stabilizer muscles to a lesser intensity and feature a different range of motion as well. 

Even if one were to account for the amount of weight being “taken off” by a smith machine, it does not entirely equate the smith machine squat with any other exercise.

Is the Smith Machine Squat as Effective as the Squat?

No - for nearly all training goals, the smith machine squat is worse than many of its counterparts. 

However, it is quite useful when utilized specifically for working the quadriceps - or in cases where rehabilitation of minor muscular weaknesses is needed.

Why do Squats Feel Harder on the Smith Machine?

In truth, squats shouldn’t feel harder on the smith machine unless you’re doing them incorrectly. 

It is important to perform smith machine squats with proper form, and additional attention paid to the position of the bar atop the back.

In Summary

The smith machine squat is effective when used correctly, and can be a boon for any bodybuilder or similarly hypertrophy-focused lifter. 

However, one should keep in mind that smith machine squats are among the most hotly debated exercises for a reason, and it is generally inadvisable for novices or previously injured individuals to perform the smith machine squat without professional supervision.

Make sure to perform it with additional attention paid to proper form - and to consult a professional if you’re unsure of anything. 

References

1. Schwanbeck S, Chilibeck PD, Binsted G. A comparison of free weight squat to Smith machine squat using electromyography. J Strength Cond Res. 2009 Dec;23(9):2588-91. doi: 10.1519/JSC.0b013e3181b1b181. PMID: 19855308.

2. Migliaccio GM, Dello Iacono A, Ardigò LP, Samozino P, Iuliano E, Grgantov Z, Padulo J. Leg Press vs. Smith Machine: Quadriceps Activation and Overall Perceived Effort Profiles. Front Physiol. 2018 Oct 23;9:1481. doi: 10.3389/fphys.2018.01481. Erratum in: Front Physiol. 2018 Dec 21;9:1856. PMID: 30405437; PMCID: PMC6206431.

3. Cotterman M. L., Darby L. A., Skelly W. A. (2005). Comparison of muscle force production using the Smith machine and free weights for bench press and squat exercises. J. Strength Cond. Res. 19, 169–176. 10.1519/14433.1