What is it?
- Sub-acromial impingement (SAI) is likely the most common shoulder complaint that presents from Crossfit.
- It occurs when the soft tissue structures of the shoulder gets pinched by the AC Joint
- Can be caused by the complex and dynamic nature of many of the exercises involved in WODs.
- Kipping, Power Cleans, SDHP etc.
- Sub-acromial impingement can occur due to many reasons:
- Most common (and preventable) in the sporting shoulder are biomechanics, activities (Like exercise), and strength factors
- Genetics may also contribute
Let’s look at the biomechanical and activity related factors one by one so you can:
- Assess if they are an issue for you
- Improve upon them before they become a source of pain.
Poor resting posture:
Many people who work in desk jobs or do a significant amount of resistance training may develop an internally rotated resting posture. Poor resting posture can:
1.Narrow the sub-acromial space where your rotator cuff tendon travels through
2.Can also cause issues with your biceps tendon and sub-acromial bursa
Decreased thoracic mobility:
1.Spinal mobility is crucial in maintaining lifting positions, especially overhead lifts and squats.
2.Normally, a thoracic spine can extend between 25-45° and flex between 20-45°