The latissimus dorsi is a long name for a large muscle with a big identity crisis. Is it a back muscle? Is it a shoulder muscle? Is it the remnants of the wings we once used to fly from land mass to land mass? Just kidding. We never had wings. However, the lats as a pair have a winglike quality when well-developed. Take Olympic swimmer Michael Phelps, for example; it’s like looking at a threatened king cobra.
The lats are huge, but they don’t act alone. Most anatomists would categorize the lats as back muscles. The pair does, to their credit, take up a large portion of the lower and lateral posterior torso. Originating along the lumbar spine, the thoracolumbar fascia, and the posterior hip, the lats blanket the deeper muscles of the low back before twisting into a bunch in order to squeeze under the armpit and reach around to grab onto the front of the humerus. And when the latissimus dorsi contracts, the arm gets pulled down to the torso, which some refer to as shoulder adduction. So, is it a back muscle that moves the shoulder, or a shoulder muscle that lives in the back? Yes, to all the things. Why would it be simple? Anatomy never is.
There are a couple of very important truths to remember when approaching the lats. While the lats play an important role in doing pull-ups, swimming, or pretending to be Spider-Man, they also rely on other muscles to keep things stable—in the shoulder, they lean on the help of the teres major, the rotator cuff, and the pectoralis to name a few. And in the back, well, this is where things get even more complicated.
When a client presents with shoulder or low-back pain, pay attention to the lats and see what they reveal.
The low back—infamous for falling into dysfunction—is well layered. The erectors, the quadratus lumborum, the obliques, and even the lower trapezius are all vying for property here. These are powerful muscles that often find themselves tipped out of balance from a lack of strength in their antagonists: the abdominals. Commonly neglected, the abs depend a little too much on the strength of the back. If the abs are weak, then the back gets tired. And you know what happens when we get tired—we get grumpy and irritable, and nothing good comes from that.
What Comes Next?
So the lats find themselves in a bit of a pickle. They’re trying to do their job but also trusting that a lot of other muscles will uphold their end of the bargain. When the lats engage, it should be like pressing the turbo button on a sports car. Everything should ramp up, but this is often not the case. While it’s easy to investigate the shoulder when the lats start getting irritated (they move the shoulder, after all), if the abs aren’t ramping up with the rest of the team, the lats can blow a gasket. All of this to say, when a client presents with shoulder and/or low-back pain, pay attention to the lats and see what they reveal.
With your client prone, start with compressions into the glutes and transition with one hand on the lower back. Sliding from medial to lateral with flat finger pads or a flat palm while you hold your compression into the glutes will allow the lats and all the surrounding layers to begin to breathe. Work your way up to the mid back, continuing to push the tissues away from the spine, and offer them permission to let go.
Bring your client’s arm off the table at a 90-degree angle and follow the fibers of the lats as they narrow toward the axillary region. This is when we can grab the lats and separate them away from the underlying tissues. While this work is awesome and can be paired well with some active internal and external rotation of the arm, I suggest swapping that out for some anterior and posterior tilts of the pelvis. Check in to see if there is a relationship between the lats and the abs. Your client might have a breakthrough, revelatory moment regarding their shoulder and/or low-back pain.
From here, extend your client’s arm up toward the head of the table and, holding at the elbow with one hand, use your other hand to brace the top of their same side hip. Ask your client to pull their hip up toward their shoulder against your resistance. See what muscles engage and what muscles stay relaxed. Play around with slight differences in the positioning of the shoulder and the hip and let your client’s lats talk to you about what is going on.
The Takeaway
There are many incredible techniques to stretch and relax a tired latissimus dorsi, but getting to the root of why it’s so tired is going to be the most effective one. Educate your clients about this incredible muscle. Find out if the lats are getting the support they need from the surrounding tissues and talk to your client about the importance of balance.
We all need somebody to lean on. The lats are no different.
