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Southington CrossFit Blog – Dr. Hawley’s Health Corner
Posterior Chain Weakness
Your posterior chain is one of the most important parts of your body and one that is most commonly neglected.  This is especially true with CrossFitters due to the invention of the “Kip”.  One of the best ways to train and strengthen the posterior chain is by performing strict pull-ups, spending time on the row machine, performing ring pull-ups or performing bent over rows.  These three exercises (some may argue the row machine) are not always performed on a daily basis within the CrossFit programing.  There are many reasons for this but this does not mean that these exercises are not important.  
For our purposes your posterior chain will be described as the upper trapezius, rhomboids, teres major and latissimus dorsi.  These are the main muscles that comprise your upper, mid and lower back.  Without proper strength of these muscles it will be almost impossible to lift maximum weight over your head and will most likely result in injury.  
The main actions of your posterior chain involve pulling and holding object into your body but are also strongly involved with stabilizing your shoulder and arm when they are moving away from the body.  These muscles are particularly important when performing snatches or kipping pull-ups.  Both of these motions put your shoulder in a precarious position if your stabilizers are not working properly.  This could explain why you sometimes have posterior shoulder pain after performing a lot of snatches or a lot of kipping pull-ups.  
Without having proper strength in your posterior chain your shoulder can easily slide forward while your arm is over head which creates a pinching sensation in the back of your shoulder.  The best way to try and prevent this from happening is to spend some time strengthening your posterior chain. 
Take a few days a week and spend some time after class focusing on the above exercises.  You will notice a huge change in your shoulder stability after only a few weeks of working your posterior chain.