The squat is among the most common exercises used by athletes participating in strength training. It is also one of the most functional strength exercises that can be performed to mimic movement patterns performed in activities of daily living. The many variations of the squat train the glutes, quadriceps, hamstrings, calves, abdominals, and spinal erectors at the same time. The purpose of this article will be to examine the differences between the back squat and front squat.
The most obvious difference between the two squat variations is bar positioning. In the back squat, the barbell is rested on the upper trapezius muscle. The front squat positions the barbell across the anterior deltoids and clavicle. The positioning of the barbell in the back squat requires more shoulder range of motion than that of the front squat. Therefore, front squats may be the best option for those with limited shoulder external rotation.
Studies examining the differences at the knee between the two squat variations have found the following. Shear forces within the knee did not vary but compressive forces were higher in the back squat than the front squat. No significant differences were seen in muscle activity although there were some differences in average EMG values. Knee extensor moments were greater in back squat but this can be attributed to greater loads used in testing the back squat. No differences were observed in knee joint angle throughout both squat movements.
Barbell positioning in the back squat requires more forward lean of the upper body to keep the center of the weight over the toes. In contrast, the anterior weight position in the front squat requires a more upright torso to maintain the center of weight above the base of support. This more vertical spinal position results in increased compressive forces on the spine but decreased shear forces. This is good as shear forces are worse for the spine than compressive. The increased forward lean in the back squat often leads to rounding of the lower back in the bottom position of the squat- this can easily be seen when watching novice lifters perform a back squat.
Diggin et al. compared both the front and back squat and concluded that “the front squat would present the least risk of injury to the lower back and knee joint, while offering the same ability to strengthen the knee extensors as the back squat technique. The front squat also allows the performer to maintain a more upright posture throughout, a characteristic congruent with most sporting techniques (e.g.: sprinting). This would imply a greater level of specificity for this technique. It is recommended that coaches and exercise professionals consider these points when prescribing a specific squatting technique.”
Conclusion: Neither the front squat nor the back squat are bad exercises. I am in no way trying to say the back squat should be avoided. But like any exercise prescribed to a patient or athlete, the individual must be considered. Coaches should never consider an exercise a “must have” as each athlete is different. Because of the more upright torso positioning, the front squat may be easier for beginners to learn and may be a better option for those who round their backs or have shoulder dysfunctions.
Gullett et al., Journal of Strength and Conditioning Research 2009
Clancy, Katherine. Comparison of Lumbar Spine Loads During Back and Front Squats. New York College at Cortland.
Diggin et al., Portuguese Journal of Sport Science 2011.