The squat has been heralded as the king of exercises from strength and conditioning coaches for years. It is revered as so because of the demand it places on the entire system from overall muscle recruitment and proprioception to its effects on the endocrine system and metabolism. Aside from the squat being thought of as a superior exercise, strength coaches have adapted the exercise to many different variations. 

In a study by Swinton et al. (2012), the authors take a closer look at the biomechanics of three squat variations – the traditional squat, the powerlifting squat, and the box squat. The authors chose these three forms of a squat because of different biomechanical advantages each have and compared it to one another The traditional squat utilizes a narrower stance, which creates a need for greater ankle dorsiflexion and knee flexion. The vertical displacement achieved with a narrow stance causes the knees to “travel past the toes” placing greater amounts of torque upon them. Alternatively, the powerlifting squat utilizes a wider stance. The wider stance causes a more vertical placement of the shin, which leads to more torque being placed around the hips. Additionally, the wider stance needed for the powerlifting squat places the torso in a more horizontal posture, which is thought to create more shearing forces on the lower back. Lastly, the box squat utilizes a wide stance much like the powerlifting squat with the addition of a box placed behind the lower leg. The box acts. as a safety feature to catch the individual if their center of mass falls behind their base of support. The individual lowers themselves to the box to allow their hips to displace posteriorly as much as possible and then concentrically generate as much force as possible. What Swinton et al.’s (2012) study shows is that despite common belief of the traditional squat to be most beneficial, it in fact places greater strain on the lower back than the powerlifting squat. 

This study also shows that there is greater muscle recruitment from the powerlifting and box squat because of additional abduction/adduction and internal rotation angles of the lower extremities. This translates to less shear forces on the lower back due to more recruitment of the posterior musculature.

            Despite what Swinton et al. (2012) measured and concluded in their study, individuals have a unique anatomy, which may lead the individual to favor one stance over the other. If an individual has the flexibility at the ankles, knees, hips and torso to perform a traditional squat, it may be the most optimal stance for them. Based on personal experience, the powerlifting squat has proven to be most beneficial for my anatomy. Unlike the evidence found in Swinton et. al. (2012), I’ve had no lower back issues since utilizing this stance. The authors concluded in their study that the box squat should be used as an additional exercise to aid in the development of explosive power. My view is that this exercise should be avoided due to the increased amount of ground reaction forces our lumbar spine withstands in a seated position versus when standing. By adding additional weight in a seated position, as in a box squat, there is greater room for lower back injury and better ways to work on explosive power. Furthermore, since every individual’s anatomy is unique, an important take away is that if you have been experiencing low back pain from squatting, perhaps try the powerlifting squat and see if it is right for your anatomy. 

David Schwartz, SPT

Dr.Brandon Cruz PT,DPT

Board Certified in Orthopedics

Board Certified in Sports

Fellow American Academy Orthopedic Manual Physical Therapy 

Certified Strength & Conditioning Specialist

References: 

Swinton, P. A., Lloyd, R., Keogh, J. W., Agouris, I., & Stewart, A. D. (2012). A biomechanical comparison of the traditional squat, powerlifting squat, and box squat. The Journal of Strength &         Conditioning Research, 26(7), 1805-1816.