Now a number of people will tell you that if you don't go below parallel then you're not squatting correctly.
Here's where I have a problem with that advice.
1. They never quantify what they mean by parallel is it the top or bottom of the thigh?
2. They do so with out looking at the individual and what that individual can do.
This is the more important of the two and the part which I am going to discuss further.
Lack of squat depth is generally due to either a lack or strenght, a lack of flexibility or both?
In fact both cases can be true.
Increasing the strength levels will allow the body to recruit more nerves and more muscle fibres which will indeed allow for greater depth to be reached.
More important is the deep squat needs a large range of motion and flexibility and alot of people lack this.
The body needs to be flexibile throughout the whole posterior kinetic chain in order to squat correctly.
If any one point in the body is unable to give enough flexibility to the movement then the movement should be compromised in depth and range.
For instance if the muscles in the calf that cross the ankle are tight then the correct amount of movement around the foot and shin will not be possible and the body will have to compensate by rounding the lower back in order to still complete the specified movement range.
To my mind this is ridiculous, the last thing you want to be doing with a big heavy load on your back is rounding out the lower back.
What happens here is the discs of the spine are put under an enormous amount of stretch and pressure (not in a good way) that generally leads to injury.
At best you may well just tweak the ligaments in the worst cases you may well damage the disc so badly that you are unable to perform daily tasks such as walking, sitting, standing and climbing stairs.
I remember watching a programme on the BBC about the UK wheelchair basketball team's training in readiness for the Athens Olympics.
One of the featured players was in fact almost a professional basketball player for real.
Unfortunately he explained in the show that he was squatting in the gym one day and had an accident whilst squatting with a heavy weight and going into a 'deep' squat.
The resultant spinal injury left him unable to pursue his career as an able bodied basketball star and meant he had to convert to wheelchair basketball as he could not run or jump any longer.
I have put together a YouTube video showing you how to complete the squat with the ideal alignment for the knees, low back and many other key points.
You'll find it here:
http://www.youtube.com/watch'v=dbxxs1PErLQ
I have had quite a few emails commending me and others telling me I don't know jack about squatting as the video shows a far from perfect and in fact 'shallow' squat.
The video depicts a friend of mine who has had reconstructive surgery on both knees (twice on the left) and has a plate in his ankle from a fracture dislocation (which basically means his foot was facing the wrong way - pointing backwards).
He is a professional rugby player and someone who is incredibly strong and powerful for his size. He is unable to go the 'full' depth because of the above mentioned reconstructive surgery.
The problem as I mentioned at the start is the inexperience or misunderstanding of many trainers and gym goers that unless you are squatting fully you aren't squatting at all.
If he was to squat to a deep position he would actually lose his low back position putting him at a greater risk of injury. At least this way he gets to squat and still play sport at a professional level, unlike the poor basketball player.
The take home message is this.
You should only squat to a depth where you can maintain ideal alignment. Any deeper will lead to stresses being placed upon the weakest and potentially most injurious of places. This may lower your level of sport performance or curtail it completely.
If some one tells you that you are not squatting deep enough get them to explain exactly why and where you are going wrong. If they don't pinpoint certain areas of reduced range of motion then walk away as they probably are clueless.