I say it all the time when I’m teaching: “engage your underarm muscles”. If you haven’t had a deeper explanation on what this means, you’re probably like, HUH, WHAT?
These “armpit” muscles are important to the function of your shoulders and arms. Without proper utilization of these muscles, a client will overuse the neck and the front of their shoulders. This can cause severe neck tension and contribute to shoulder injuries. To understand this better, let’s take a closer look at the anatomy.

Your shoulder blades (ie scapula) perform many different upper body movements. If your goal is to reduce neck tension (who doesn’t need that!?), the most important movement of the scapula is “scapula depression”.
No, your scapula isn’t sad, it just means your scapula moves in a downward motion.
There are a few muscles that assist with this movement: lattitimus dorsi, trapezius, pectoralis minor and serratus anterior. The fibers of the serratus anterior are shown below; notice how this muscle (along with the lats) are located in the underarm/back area.
If you’re not adept at using these muscles, you tend to overuse the muscles in your neck and shoulders. Combine this with constant texting and laptop work, and boom! You now have a tight and sore neck.
It’s important to get these armpit muscles stronger. It’s also very important to learn to use these muscles more frequently when lifting, typing and driving a car.
One of my clients who used to have chronic neck pain saw immediate relief within 2 weeks of learning to engage her scapula depressors!
So without any more pomp and circumstance, I present my favorite underarm muscle exercise. I call it “hand pumps supine”. You’ll see the exercise uses mini balls. Don’t have balls? Try two soup cans. Place your hands on the sides of the cans so you can roll them away from your shoulders as needed for the exercise.
Give it a GO. As it says in the video, be sure not to flare your rib cage. Also make sure your shoulders don’t tense up by your ears.
Let me know what you think. The comments box has been a bit lonely in 2017… shoot me a line below!
I can tell immediately that this is the reason for my neck/shoulder pain. I’ll be doing this exercise immediately! Thanks for posting all this information… you’re a lifesaver!
You’re very welcome!
Can you tell me what size balls to get? I know this is why I have neck tension and headaches.
You can use smaller balls… these a weighted balls that are about 3 to 4 lbs in weight. You could also use yoga blocks! These are the right height…
About 4 to 6 inches in diameter is good for this exercise!
Hi, so in this area, under my arms, I am very swollen. I haven’t used these muscles in Avery long time. I injured my neck and back 5 years ago. I have a lot of pain. Nothing can be done about it. So this area on both sides is literally firm and swollen, very painful. I’m wondering if it’s because I haven’t used these muscles like you mentioned? I’m so tired of hurting.
Swelling would indicate more than weakness… my recommendation is to see a doctor!