The Myths of the Squat and Bench Press – by Rob Wagner is a great read for anyone who as been forced to consider the injury potential of squatting ATG (ass to ground) and it is well referenced. It is worth mentioning that I have yet to receive a single citation from an ATG squatting nay-sayer about why full and deep squatting is bad from someone with healthy knees; they can be passionate detractors but lack any evidence to support their claim that it will destroy healthy knees.
Myth # 1. Squatting is bad for your knees.
Dr. Klein’s can take the credit for launching this one. Studies carried out over the past twenty years have rejected Klein’s findings. In a study that looked at the effects that full squats and half squats had on knee stability showed no change, over eight different tests for stability, when compared to a control group. To determine the long-term effects the same researchers looked at the knees of competitive powerlifters and weightlifters and found that powerlifters and weightlifters had tighter knee joints than the controls (Chandler & Stone, 1991). Another study found that the involvement of the hamstring in full squats plays a role in helping protect the anterior cruciate ligament (Manariello, Backus & Parker, 1994).
If you do squat and don’t go down very deep, you are limiting your growth potential as well as capping the sports specific performance benefits of the exercise for a few reasons:
- If you squat through 50% of the range of motion, you will need to do twice the number of reps to do the same amount of work.
- Partial squats either limit the time under tension (which is critical for hypertrophy) or force the athlete to move very slowly to achieve the time under tension. Slow movements tend not to be very sport specific.
- Partial squats do not cause the same amount of GH release because they do not force the body to work as hard.
- Partial reps do not improve strength along the entire length of the muscle belly so you will be weak once your knee flexes into the untrained range.
NOTE: there is a time and a place for partial reps if you have good knee integrity but the bulk of your squatting should be ATG deep. If you have poor knee integrity, deep squatting my not be the right exercise for you.