How far you should squat down is an age old argument.
The misguided may tell you that you shouldn’t squat past 90 degrees due to
shear pressures on the knee and the blinkered will tell you that if it’s not ass
to grass… then it’s not a squat.
So who is right? And why all the controversy?
The squat can be considered full range when your hips sit below your knees with your back in absolute extension and your knees pointing over your toes.
A Powerlifter is required to break parallel, that’s considered full depth in a Powerlifting competition. Whereas an Olympic weightlifter who pulls the bar from the ground needs to get under the bar as fast and as deep as they can in order to catch it at the lowest possible point. This means they won’t have to pull the bar as high and will therefore want to use the full “ass to grass” range.
Your individual anatomy will decide which variants you are able to do, and your goals will decide what you want to do!
So why all this fuss about deep squatting being bad for the knees?
Squatting safety continues to be a concern amongst some practitioners, particularly as it relates to performance at high knee flexion angles.
The theory that deep squats heighten injury risk can be traced to studies conducted by Karl Klein at the University of Texas. Using a self-developed measuring device, Klein noted that weightlifters who frequently performed deep squats displayed an increased incidence of laxity in the collateral and anterior cruciate ligaments compared to a control group that did not.
Klein concluded that squatting below parallel had a detrimental effect on ligamentous stability so should be discouraged. The American Medical Association (AMA) came out with a position statement cautioning against the performance of deep knee exercises because of their potential for severe injury to the internal and supporting structures of the knee joint.
Subsequent research, however, has refuted Klein’s findings, showing no correlation between deep squatting and injury risk. In fact, there is some evidence that those who perform deep squats have increased stability of the knee joint.
Brad Shoenfeld noted that “contrary to Klein’s hypothesis, ACL and PCL forces have been shown to diminish at higher degrees of knee flexion. The reduction in ACL and PCL forces associated with deep squatting is believed to be a result of an impingement between the posterior aspect of the upper tibia with the posterior femoral condyles as well as compression of various soft tissue structures including menisci, posterior capsule, muscle, fat, and skin. This helps to constrain the knee joint, significantly reducing anterior and posterior tibial translation and tibial rotation compared to lesser flexion angles.”
Hence, tolerance to load is enhanced in the deepest portion of the squat with a protective effect conferred to ligamentous structures.
So we are designed mechanically to squat deep but…were not all built the same… and everything from lifestyle to use and abuse can take its toll.
If you have biomechanical limitations due to any of the above then your ability to squat deep may be impaired. Either a change of squat variation could be needed… or an intervention…
If you can’t hit the depth that your chosen squat requires you need to focus on mobility, that is mobilizing the tight tissues and then pairing that new range with a neutrally relevant movement. In this case a squat!
When you are using optimal form for YOUR squat…the weight you can lift will increase quickly.
However, too many people (and their trainers) focus on lifting weight, no matter how it looks, than on the movement and in doing so are trying to cash cheques their body can’t write.
Or in other words… they put a weight on their body that they can’t control… or overcome… so they end up with a squat that looks more like a curtsy.
Of course there are times when a quarter-squat
or a half-squat may be included in an athletes training phase for a specific adaption or overload technique but this is an exception to the rule, not the norm.
So why shouldn’t you load up a heavy bar and have your client do partial range squats?
Well, when you perform full range squats, you move the body through its complete anatomical range and develop strength over that range, and complete development and coordination of the muscles involved.
The full range squat is the position you spend the first 9 months of your life, and is a position toddlers can manage (now loaded in gravity) with ease.
Remember our ancestors used to perform many daily functions (i.e. harvesting, gathering, hunting, cooking, eating, etc.) in a full squat position.
When you perform partial squats you are able to load the bar with more weight than with full range squats but you only strengthen the range you move, and this can have serious consequences on your back (as you must control a supra-maximal load) and your knees (as 90% is the position where most shear stress occurs and you don’t have full gluteal and hamstring activation to co-contract against the
So your first goal is to achieve the positional requirements of your required squat. If you have any mobility (or neural) issues holding you back then fix those up before you throw on the load. Once the form and depth are right….
…the force will come!