Myth Busting: THE SQUAT
ARE DEEP SQUATS BAD FOR YOUR KNEES?
Today we’re going to address one of the biggest myths in weightlifting and exercise - the idea that deep squats are bad for the knees.
Squats are by far one of the most important exercises out there, for a number of reasons. While targeting prime movers like quads, hamstrings, and glutes, a squat done with good form also engages the muscles of the core and improves spinal stability. Squatting also improves bone density, regardless of your age group.
Unfortunately, a nasty rumor began about deep squats being bad for the knees. The idea is essentially that as you squat down, the patella is compressed into the knee joint, which leads to degeneration that wouldn’t occur otherwise. This led to many coaching cues and advice about performing partial and half squats in favor of full squats.
Fortunately, a 2013 paper titled Analysis of the Load on the Knee Joint and Vertebral Column with Changes in Squatting Depth and Weight Load, should put this rumor to bed. The authors found that in individuals with healthy knees, fears about deep squats were unfounded.
Shear forces on the knee, which put soft tissues like the ACL and PCL at risk, peak at about 90 degrees. Beyond 90 degrees, there appears to be no additional increase in shear forces. Although compressive forces peak at full flexion, the force becomes more widely distributed throughout the muscles due to a wrapping effect of the quadriceps around the femur. Along with this, the glutes are more active the deeper you squat.
Given the fact that most forces peak at 90 degrees flexion, doing partial squats may actually be more damaging than performing deep squats. Presumably, the person performing partial squats will be using more weight, meaning even higher forces.
As with most movement, proper form is the key. If you focus on mastering the movement before progressing to heavier weights, there is no reason why you should fear for your knees.
For some, this is probably great news and reason to continue training with a renewed confidence. For others, I apologize for destroying your excuse for not wanting to perform a very uncomfortable exercise. In either case, squat often and squat deep.