Introduction

The front squat (FS) has been the ugly stepchild of the weightlifting world. Novices get intimidated by the unnatural bar placement and most amateurs settle with the fact that they have mobility restrictions that prevent them from performing the movement. Gym-goers will prioritize back squat (BS), deadlift, and leg press before they perform the front squat. Front squatting is not included in powerlifting events which focuses more on maximal weight on back squat, deadlift, and bench press. It is, however, a crucial part of Olympic lifting as the front squat is required during the clean and jerk as one stands up with the weight after catching the clean.

One of the greatest contribution that Crossfit has done so far is reintroduce movements like the front squat back into fitness enthusiasts’ lives. You have males and females in wide ranges of ages and lifting experience that all perform the front squat because it is routinely incorporated into their programming.

There have been many myths and Broscience idealism that surround the front squat. Things that you’d regularly hear such as “front squats don’t really target the glutes” or that “back squats hurt my lower back” are all based on someone’s truth, but have yet to be proven or disproven. There is also that intuition that because you perform the front squat with less weight, that you won’t get as much gains from it.

I have been in your position and have long believed some of the Broscience. I decided to dig into the research and try to bust some of the long-standing gym myths. My hypothesis before I started this project was that both front and back squats are good for you and should always be incorporated into your programming.

To skip to the summary, scroll to the end of the article. Let’s get started.

I get more glute activation with the back squat

Contreras et al (2016) compared the upper and lower glute max activation in parallel BS vs full ROM BS vs front squat in resistance trained females and found no statistical difference in glute max activation between the three lifts.

Another study by Yavuz et al (2015) found that EMG activity of the glute max was also similar with back and front squats performed to 90 degrees of knee flexion

One study found that the glute max recruitment increased the lower you go with a back squat (Caterisano, 2002).*

Another study by Bryanton et al (2012) supported that going deep and heavy in a back squat are both required for increased work of the glute muscles.*

Consensus: Go deep and heavy with the back squat for increased glute max work

Although the current body of research is currently inconclusive on glute max recruitment and squat depth with the front squat, there are a few studies that demonstrate the competitiveness of the back squat vs front squat in glute max recruitment. Yavuz et al (2015) found similar glute max recruitment but the squats were only performed to parallel. Contreras et al found similar glute max recruitment with a deep squat vs front squat, but the study consisted of female subjects only therefore its generalizability is currently limited

Final Word:

Don’t neglect the front squat because you only want to focus on your glutes. Even though the back squat has a slight edge on hip extensor recruitment the edge is not that significant at this time. Future studies may focus on glute max recruitment with going deeper and heavier during the front squat.

If you really want to work your gluteus maximus, try the Barbell Hip Thrust exercise. More and more studies are coming out recently at how this exercise may translate to improved athletic performance (Contreras et al. 2014)

Front squats are quad builders

One study found statistically similar vastus lateralis recruitment in parallel squat vs full ROM squat vs front squat despite the load differences. The subjects used the most load with the parallel squat and the least amount of load with the front squat.

• During the front squat, the quads were recruited 21.5% more at peak EMG measures vs its counterparts despite using lighter loads. Unfortunately, there was also a large effect size so this number was not found to be statistically significant
• The front squat may provide similar training stimulus despite using lighter loads (Contreras et al 2016)

The bar placement had very little influence quad recruitment in the BS vs FS; however, this study found a statistical difference in muscle activation between the ascending vs descending phase of the squat

There was decreased tibiofemoral compressive forces and knee extensor moment with the front squat (Gullet, 2009)

Increased knee extensor relative muscular effort (RME) with increase in back squat depth, not an increase in load (Bryanton, 2012)*

One of the only statistically significant findings in a study by Yavuz and his colleagues (2015) was that the vastus medialis muscle had higher EMG activity with the front squat during the ascension phase vs the back squat

Consensus: The front squat is a quad builder.

If your primary goal is to get bigger and stronger quads, the front squat would be the route to go. This is because you are able to achieve similar training stimulus with less weight while having a significantly lower compression and shear forces acting within the knee joint.

Final word:

The back squat is one of the staples of many workout routines for a reason. It has excellent hip and knee extensor recruitment especially when going in deeper ranges. The back squat also allows you to lift heavier loads which can help with training your central nervous system as well as improving overall strength and power generation for athletic performance. The front squat is a really good adjunct especially if you are trying to increase your quad hypertrophy. It is also really good if you have knee pain when going into a deep squat; it’ll allow you to build up your quad strength to build up your resilience to knee pain in the future.

My hamstrings don’t need work because I squat

Biceps femoris and semitendinosus EMG amplitude was not influenced by front vs back squat back positions (Gullet 2009)

The only difference that Yavuz et al (2015) found was that there was a statistically significant difference in semitendinosis EMG activity with the ascension phase of the 90 degree back squat

Greaters biceps femoris EMG activity amplitude with deep back squats vs parallel squats (Wrentenberg 1996)*

No observable difference in biceps femoris activity in a comparison of parallel BS vs full ROM BS vs front squat (Contreras 2014)

Consensus: Squatting was insufficient for hamstring development (Ebben et al 2000)

Final word: If you have goals of hamstring development, it may behoove you to add the stiff-legged deadlifts, leg curls, or nordic hamstring curls to supplement your squats. The hamstrings assist the ACL in limiting the anterior translation of the tibia and the subsequent shear forces therefore it is important to maintain hamstring strength in your training

Back squatting strengthens my lower back

There was no significant difference in erector spinae EMG activity in front squat vs back squat (Yavuz et al 2015)

Bar position had no influence on the erector spinae muscle activity (Gullet et al. 2009)

The front squat had higher erector spinae activity vs the BS even with light to moderate load (Comfort et al. 2011)

The increase in trunk lean increases shear forces within the lumbar spine, but its contributions to injury is not known (Yavuz et al 2015)

The increase in trunk lean may result in greater shear in the lumbar spine which may pose an increase in injury risk (Comfort and Kasim. 2007)

One study found a significant 37.8% difference at maximum trunk lean between the back squat and front squat which may translate to an increased risk in lower back injury when performing the BS (Diggin et al. 2011)

Consensus: Front squat if you have lower back pain

Final word: Most studies had similar EMG activity for the back muscles with the squats. The back squats do cause an increase in lumbar shear forces because you have to bend forward as you descend in your squat. If you want to strengthen and improve your lumbar extensors, deadlifting may be the way to go.

I can’t squat because my knees hurt” or “I just had knee surgery recently

The two joints that make up the knee joint are the tibiofemoral joint and the patellofemoral joint. Either or both of these joints can be responsible for pain within the knee during front or back squats.

The two primary forces that could result in pain with movement within the knee joint are the COMPRESSION and SHEAR forces. Compression force is the application of pressure or power that causes two objects to become squeezed or compacted. Shear force is a force that pushes on object in one direction, while pushing the other object in another direction. Some of the research studies investigate these two forces, so we’ll start with what they have to say about the shear forces

Shear forces

Peak shear forces occur when the knee is flexed 85-105 degrees. In this position the hamstrings create a posterior shear force on the tibia.

Shear forces during the front and back squat were posteriorly directed, but small in magnitude and did not vary with bar placement (Gullet, 2009)

Escamilla et al (2001) reported that the tensile forces on the ACL is potentially non-significant which may be due to the moderate hamstring activity that helps unload the ACL during squatting

Bouncing at the bottom of the squat increased shear forces by up to 33% (Ariel. 1974)

Subjects with the greatest knee motion in the forward direction had the highest shear forces (Escamilla et al. 2001)

Compressive forces

The lower you go past parallel, the more the compressive forces in the patellofemoral and tibiofemoral joints (Escamilla et al. 2001)

Net compressive forces and knee extensor moments increased for the back squat; however, it must be noted that in the experiment the back squat load was heavier vs front squat load (Gullet et al. 2009)

Consensus: Front squat if you have knee pain or just had meniscus surgery. Squatting in general is safe for ACL reconstruction rehab

Final word: Compressive forces within the knee joint is one of the primary causes of pain while squatting. The front squat allows you a similar training stimulus with less knee joint pressure. Gullet et al. (2009) states that compressive loading is an important variable when joint health is a concern. If you have decreased cartilage or previous meniscal pathology, the front squat may be the best exercise to maximize lower extremity gains in the long-term. There is a strong body of evidence that demonstrate that squatting is safe of ACL rehab, though it may be best to start in partial ranges and then progress to parallel/full ROM as tolerated.

I need more upper body mobility to be able to Front Squat

The front squat is good for people with shoulder range of motion problems required for back squat (Gullet 2009)

Consensus: The front squat is an excellent exercise if you have shoulder range of motion limitations

Final word: Most people with shoulder pain will have a difficulty with getting into that abduction + external rotation required to get into the back squat position. This is also tough for people with shoulder microinstability as they feel as if their shoulder might pop out forward. The simple modification with the back squat is to widen out your hand placement and/or go low bar.

The front squat requires less external rotation in the clean position and the compensation of doing the crossarm hold has very minimal shoulder range of motion requirements. Where people get tripped up is with their wrists, but again for people with wrist problems, the crossarm is a great modification that puts minimal stress on the wrists

Conclusion

It is interesting to note how much of “Broscience” holds up with the literature review. This may be due to Broscience originating from years and years of real life experience from weightlifting veterans. I am surprised at how the EMG activities are grossly similar for squatting despite the bar placement. I was also shocked to see how underrated an exercise the front squats were for the many benefits it was able to provide. My hypothesis was that both the FS and BS should be regularly incorporated into your workout routine and it holds up. Truthfully, it all depends on your individual goals and whether those movements will help you achieve them

The research studies are far from an be all end all as each of them have their own limitations. There were common themes and findings that arise from the studies presented above that could help guide your decision making in choosing one over the other. Most of the studies have subjects with the average healthy person in mind which may or may not apply to you. You can’t replace a medical professional that evaluates you personally and identifies your specific limitations to completing the movement.

If you liked this information, I would appreciate if you subscribed to this blog and stay tuned for my next post “Fortifying your Front Squat” where I go over common front squat limitations and provide drills and exercises to help address them

*notes that the study did not compare back squat versus the front squat

Summary

• Glute development: Back squats get the edge. The deeper and heavier, the better
• Quad development: Front squats! Even with less weight they get worked
• Hamstring development: Both are poor choices if hamstrings are your focus. You have to do some form of deadlift to strengthen your hammies
• Lower back pain: Front squat if you have back pain. Both BS and FS have similar back muscle activity, but BS causes you to lean forward more
• Knee pain: Front squat
• Meniscus surgery: Front squat
• ACL rehab: Both are safe, but start with partial squats and progress from there
• Shoulder range of motion limitations: Front squat
• Wrist range of motion limitations: Back squat

References

Ariel, BG. Biomechanical analysis of the knee joint during deep knee bends with heavy loads. In: Biomechanics IV R. Nelson and C. Morehouse, eds. Baltimore: University Park Press, 1974. pp. 44-52.

Bryanton MA, Kennedy MD, Carey JP, Chiu LZ. Effect of squat depth and barbell load on relative muscular effort in squatting. J Strength Cond Res. 2012;26(10):2820-8.

Caterisano A, Moss RF, Pellinger TK, et al. The effect of back squat depth on the EMG activity of 4 superficial hip and thigh muscles. J Strength Cond Res. 2002;16(3):428–432.

Comfort, P., & Kasim, P. (2007). Optimizing Squat Technique. Strength and Conditioning Journal. 29 (6), p10-13.

Comfort P, Pearson SJ, Mather D. An electromyographical comparison of trunk muscle activity during isometric trunk and dynamic strengthening exercises. J Strength Cond Res. 2011;25(1):149-54.

Contreras B, Vigotsky AD, Schoenfeld BJ, Beardsley C, Cronin J. A Comparison of Gluteus Maximus, Biceps Femoris, and Vastus Lateralis Electromyographic Activity in the Back Squat and Barbell Hip Thrust Exercises. J Appl Biomech. 2015;31(6):452-8.

Diggin D, O’Regan C, Whelan N et al.,“A biomechanical analysis of front vs. back squat: injury implications,” Portuguese Journal of Sport Sciences, vol. 11, no. 2, pp. 643–646, 2011.

Ebben WP, Leigh DH, Jensen RL. The role of the back squat as a hamstring training stimulus. Strength Condit J. 2000;22(5):15.

Escamilla, R.F., Fleisg, G.F., Lowry, T.M., Barrentine, S.W., & Andrews, J.R. (2001). A threedimensional biomechanical analysis of the squat during varying stance widths. Medicine and Science in Sports and Exercise. 33 (6), p984-998.

Escamilla, RF. Knee biomechanics of the dynamic squat exercise. Med Sci Sports Exerc 33: 127-141, 2001.

Gullett JC, Tillman MD, Gutierrez GM, Chow JW. A biomechanical comparison of back and front squats in healthy trained individuals. J Strength Cond Res. 2009;23(1):284-92.

Wretenberg P, Feng Y, Arborelius UP. High- and low-bar squatting techniques during weight-training. Med Sci Sports Exerc. 1996;28(2):218–224.

Yavuz HU, Erdag D, Amca AM, Aritan S. Kinematic and EMG activities during front and back squat variations in maximum loads. J Sports Sci. 2015;33(10):1058–1066.