Oh the Lats! Easily one of the internet’s favorite muscles. Can’t reach overhead? Gotta be the lats. Can’t do pull-ups? Better train those lats. On a trip to bat wing swole town? Gotta hit those lats! I must say, these muscles get a lot of attention.
However, one area where I think they also play a role is in shoulder pain. Before I explain, a little anatomy about the lats, also known as latissimus dorsi:
- The lats attach from the humerus (upper arm bone), down to the thoracolumbar fascia, which inserts directly into the pelvis. You can see this in the picture of the lats in red.
- The lats function to extend and internally rotate the arm as well as to extend the lumbar spine (the latter being a lesser known thing I find)
- When restricted, the lats have the potential to limit shoulder flexion (bringing the arms overhead), external rotation (rotating the thumb back) and lumbar flexion. We’ll be focusing more about what is limited in the shoulder specifically.
I’ve always stated that trying to perform overhead exercises with largely restricted overhead motion is a bad idea. Well, it makes sense. If you’re lacking overhead mobility and you force your way into more overhead mobility under load, that doesn’t seem like a good idea right?
That’s a bit of a no-brainer, but why is it bad?
Think of it this way. Let’s take an athlete with restricted overhead mobility due to lat shortness and have them perform a kipping motion:
There is a lot of momentum forcing additional overhead mobility in the backswing (arch) of this kip huh? Well, what is going to happen with our athlete with stiff lats? For one, your body will compensate in the backswing of a kip. Compensation can be seen in several ways:
- The hands get much wider
- The elbows will bend
- The lumbar spine will arch excessively
- The backswing will be limited in motion
- The shoulder will internally rotate
#5 is what interests me. Watching Mike Reinold’s video the other day on lat and teres major restriction got me thinking:
If the lat (and teres major) are limited they will force the shoulder into more internal rotation at end range shoulder flexion. We’re doing this same thing in the back swing of kipping movements (just under a lot more load). Now, this situation reminds me of one of my favorite orthopedic assessments. The good old Neer’s Test for Shoulder Impingement Syndrome:
All kidding aside, bringing the arm into forceful full flexion with the shoulder in internal rotation causes compression of the biceps tendon, supraspinatus and subacromial bursa by the coracoacromial arch. This forceful compression could be causing subacromial impingement syndrome of the shoulder.
To learn more I’ve beaten subacromial impingement to death in an article series you can find HERE:
Take an athlete with limited lat mobility and ask them to perform loaded movements at end range and you might be giving them some hearty subacromial impingement syndrome. To make matters worse, if the athlete has decreased thoracic extension, decreased rotator cuff control, decreased scapular posterior tilt and scapular upward rotation then we’re probably getting even more compression of those tender subacromial structures. Good luck rotator cuff, it was nice knowing you.
We always knew that training overhead motion with severe overhead restrictions (Like tight lats) was a bad idea, this is my best guess at the mechanism of injury for why it is happens.
Want to learn more about how to assess overhead motion and find the best exercises to correct it? Check out Dr. Dave Tilley and my product:
Monkey Method – Movement Essentials
The Ultimate Guide to Understanding and Fixing Technical Flaws in the Handstand, Muscle-up and Olympic Lifts
Let’s get those lats swole and flexy,
Daniel Pope DPT, CSCS
References:
- Woodward, T., & Best, T. (2000). The Painful Shoulder Part 1: Clinical Evaluation.American Family Physician. Retrieved June 5, 2016, from http://www.aafp.org/afp/2000/0515/p3079.html