Pec-Scapular Stabilizer Interaction

The old adage usually holds true that “every action has a an opposite and equal reaction.” With the human body, that usually means that if there is a restriction somewhere, there will be an issue somewhere else. As it pertains to the shoulder, a restriction in the Pecs (especially Pec Minor) will cause a poor activation in the muscles which stabilize the scapula (Rhomboids, Middle and Lower Traps).

You will know when you see someone with poor pec flexibility. They are usually hunched over with a rather kyphotic stance. They will appear to have a large and broad back. The humeral head is rotated anteriorly. This position alone is cause for problems, simply due to the position of the humeral head in the joint, causing internal impingement.

The other major problem with a tight set of pecs is that when they’re tight, the muscles of the upper back, which stabilize the scapula are ina stretched position. Muscles don’t work well when constantly stretched and become very fatigued quickly which compromises shoulder health.

Good Foundation – Good House

Why is good scapular stability important? The scapula is the foundation for the shoulder. Without a good foundation, your house will crumble. The same is true of the shoulder. If the muscles that stabilize the scapula aren’t strong and stable, the shoulder will crumble.

Remember that the rotator cuff is responsible for keeping the humeral head in the right position and rotating correctly. The rotator cuff originates on the scapula. If the scapula is unstable and moves excessively, the rotator cuff has to work excessively to keep the shoulder working correctly. This excessive work leads to tendonopathy, impingement and instability.

The moral of it all, keep the pec minor and major stretched out to help keep the humeral head in a good position and give the scapular stabilizers the best opportunity to work at their best.