Some of you may have heard of the name Charles Poliquin as he is one of the world’s most successful strength coaches. He has trained Olympic medalists in 17 sports and world record holders in 10 different sports. So when he makes a comment such as “if you are not going past parallel, you’re not getting much out of the exercise,” it is worthwhile finding out why. The squat has probably got more negative press over time than any of your other favourite exercises. It has been blamed for knee problems, back problems and many exercisers choose to avoid it like the plague. So lets peel off a couple of myths to start finding the answer.
Deep squats past parallel are to blame for knee problems
This started back in 1961 with a poor study design that supported the myth that the knees of deep squatters are more unstable than those of partial squatters. Unfortunately the myth remains in spite of many recent studies which support the opposite.
Powerlifters squatting more than twice their body weight to depths of 130 degrees at the knee were shown to have more stable knees than those who didn’t squat. This is also supported by studies which show deep squats activate the gluts and hamstrings (and to a lesser extent the adductors – inner thighs) more than twice that of a partial squat which in turn balances up the anterior and posterior (forward and backward) forces on the knee (and produces less stress on ligaments). Lack of depth allows the quadriceps to dominate which in turn places anterior (forward) stress on the knee and more stress on ligaments.
Any sprinting activity requires large servings of glut and hamstring contraction so it makes sense to train the strength part of sprinting power with a deep squat. In most gyms you will find that partial squats are common and deep squats are rare.
Deep squats hurt your back
The goal in a squat is to maintain a neutral spine. Not being able to achieve this particularly with extra load, could indeed hurt your back. The spine can handle compressive forces if it remains neutral and upright. However if the spine has a faulty pattern during the squat (eg. flexing or hyperextending) it will create excessive shearing in the spine which could then lead to an injury. You really need to deserve the right to add load to your body by achieving an ideal pattern first.
So we know that deep squats only have benefits if they are performed correctly. We also know that partial squats have minor benefits but these minor benefits could then create imbalances over time eg. over development of the quads at the expense of the gluts and hamstrings which will in turn create risk for knee ligaments. If in doubt about your own squat technique, get some help from a squat expert.
Poliquin, Charles. Flex, 87508915, 20120401, Vol.30, Issue 4
Caterisano A et al. The effect of back squat depth on the EMG activity of 4 superficial hip and thigh muscles. Journal of Strength and Conditioning Research. 16(3); Pp 428 – 432. 2002
Schoenfeld, B.J. Squatting kinematics and kinetics and their application to exercise performance. J. Strength. Cond. Res. 24 (12): 3497-3506: 2010
Bryanton M et al. Effect of Squat Depth and Barbell Load on Relative Muscular Effort in Squatting. Journal of Strength and Conditioning. Research Issue: Volume 26 (10) October 2012 p2820-2828