FINALLY… (I am actually confident that this is in fact NOT the last mention of the squat topic)

All of the research studies I have read over the years, and even more recently, are deemed valid, reliable and sound in evidence terms in that they give the standard detail required about their subjects start point (i.e. age, sex, ability). My question to this is that without a common ‘biomechanical’ start point or measurement then is all of this research flawed?

None cited details of a commonality in intrinsic biomechanical set up of the individuals taking part. There is no evidence of biomechanical screening for pelvic function, neural tension, muscle spasm, foot function and joint mobility prior to the research or, in fact, as part of the research. Therefore we could argue that the results are likely to be questionable, as while in some instances individuals have been deemed ‘healthy’ which <em>suggests</em> the same starting point, each participant's biomechanical set up will have affected the performance results differently according to that individual's intrinsic biomechanics.

Now I appreciate that can be argued for all factors relating to physical analysis research projects. Height, weight, medical history, genetics, prior training experience etc… but when performing a research project looking into the effects on internal structures during movement this is what makes finding valid and reliable evidence challenging. So while we can surmise a certain degree of information from these many research papers, just how valid and reliable are they?

Having been involved as a director of an education company I recognise that we are faced with this challenge on a daily basis and therefore feel very passionate about making as much evidence as valid and reliable as possible for analysis.

<strong>How does intrinsic biomechanical dysfunction affect the squat you perform and what does this mean?</strong>

Due to our modern lifestyles we sit at desks, drive for hours, perform repetitive movements and perform tasks we were not actually designed to do. What this means is the body has to compensate somehow and has attempted to evolve in some way, the result is that the compensations are causing problems. The 3 systems (nerve, muscle and skeletal) typically compensate for dysfunction in each other, such as; muscle function being affected by protective spasm. Prolonged muscle spasm can cause muscle fibrosis, which may enable the body to preserve energy by not having the whole muscle in spasm, thus creating tension in other muscles along the nerve’s pathway and compromise their function as they attempt to lengthen during activity.

Research tells us that 60% of biomechanical dysfunction in the knee comes from the pelvis. So having your hips muscles in this protective spasm can commonly result in a rotated pelvis that can create a leg length difference (LLD), for example. What I would now like to explain is what happens mechanically during a squat when you have a LLD as just <strong><em>one example</em></strong> of how the body would need to compensate to allow the body to perform this movement.

The way the pelvis works is to rotate forwards and backwards on either side alternately and independently when you walk. For example when your right leg moves forwards the right side of your pelvis rotates backwards. Then as your leg moves through gait it ends up behind you and your pelvis that side will rotate forwards. It can be at any point during this action of the hip extension and flexion (during gait or any other activity) that the muscles can become ‘stuck’ or sub clinically go into a protective spasm. The theory is that if it is during hip flexion, the leg on that side can appear shorter when measured next to the other one and vice versa. Often both hips can become ‘stuck’ leaving you with a twist to both sides. More often than not we are totally unaware of this as it can cause no discomfort directly from this type of spasm, However…

…Several things could happen…

The femur or thigh on the longer leg could rotate inwards to allow for the extra length meaning the knee/s has a tendency to turn in during the squat

This means the knee of the longer leg will be under more stress on the inside/medial ligaments. They could become stretched, weaker and damaged over time.

The shin or lower leg could also rotate inwards adding to this problem from below the knee joint as well as above.

The foot could pronate excessively and roll inwards leaving the squat unstable and increasingly less stable the lower you go in depth.

When standing, the side of the pelvis with the longer leg may appear higher than the opposite side resulting in scoliosis or a curvature of the spine. This can leave you with a ‘hinge’ in the back and weaker spots between facet joints during the squat risking damage or wear and tear. The facet joints job is to protect your discs and so it is vital we do not put them at risk.

The result of this spinal curve, known as ‘functional’ scoliosis, means local muscle spasm and loss of spinal function and mobility during the squat. If you do not have full mobility and a level pelvis, then add 100kg of compressive load on top and then squat you will be restricted in depth to maintain good, safe form intrinsically.

Loss of spinal mobility translates directly into the upper body and creates tension through the musculature of the shoulder and neck meaning there can be difficulties in bar positioning, particularly with low bar or front squats. These problems are likely to be asymmetrical too.

If you lose full shoulder capacity then problems can arise in the rotator cuff, elbows and even the wrists

Finally just as an aside; a common reason for an inability to squat to a preferred or lower depth without passing your ‘break point’ (see The Squat Part 2/6) is poor thoracic extension capabilities caused by pec minor spasm. Yes, release the chest and you could, like I did, find you can squat lower. Mike Boyle &amp; Shirley Sahrmann are both advocates of developing thoracic mobility (<em>A joint by joint approach</em> Mike Boyle &amp; <em>Diagnosis &amp; Treatment of Movement Impaired Syndromes </em>Shirley Sahrmann).

Each of these would, over time, be likely to result in discomfort, Repetitive Strain Injury (RSI) type symptoms and/or energy leaks while putting the structures at risk of an injury. So if you had pain in any of the above mentioned areas it is vital to understand that the site of discomfort or pain is not necessarily where the problem is coming from.  Each of the examples given above are as a result of some tiny muscles in the hip going into a <strong>sub clinical</strong>(asymptomatic) protective spasm. This is one of the reasons many are losing faith in the medical world. Medics and therapists are trained, and skilled up, to treat the site of pain. While some therapists do look for and address the cause of pain, it is common for this not to be done. This means that without addressing where it came from the symptoms can return and this is where you get recurring injuries and niggles that some professionals can be scratching their head over!

Remember that this is just an example, there are many more ways the body can compensate for what YOU do during your squat, with your body type, your medical history, your genetics and your biomechanical set up.

The most important thing to remember if you do suffer low grade, non-specific discomfort, pain, recurring niggles or loss of performance when you squat it could have come from anywhere! Treating the site of pain may not be a long term solution. If it comes back you have not addressed the root cause and ultimately you need to try something else!

So when you have a question about your squat technique, the depth you should go to, the type of squat you should do, the position of your spine during the squat, consider all of the things that could be affecting it because interestingly <strong>your foot could be causing your shoulder pain!!</strong>

During the writing of this article I improved my own break point &amp; technique through releasing pec minor and increasing my thoracic extension mobility……☺ so now bear with me while I start to add some weight to the bar!

HAPPY SQUATTING!!

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<strong>References</strong>

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