Shoulder Pain 101: Why It Happens and How to Fix It

You have shoulder pain.

You never really thought about your shoulders—until they started hurting, right?

For years, they worked perfectly, letting you lift, twist, and reach without a second thought. Cleaning windows? No problem. Perfecting your golf swing? Easy.

Then one morning, after what you thought was just “sleeping on it wrong,” that annoying pinch in your shoulder lingers. Days turn into weeks, then months. Now, even driving or sleeping is uncomfortable.

What gives?

Your go-to approach—“I’ll give it a week and it’ll work itself out”—isn’t cutting it anymore. If this sounds familiar, you’re not alone.

Up to 70% of people experience shoulder pain at some point in their lives. But here’s the good news:

Your shoulder pain won’t last forever.

With a few key changes, you can start feeling better today.

Understanding how your shoulders function is the key to fixing the root cause of your pain. By the end of this, you’ll know what’s causing your discomfort and how to keep your shoulders pain-free long-term.

What Is The Rotator Cuff?

Your shoulders are a good news/bad news situation.

• The good news: The shoulder is the most mobile joint in your body. It’s a ball-and-socket joint designed for lifting, rotating, and reaching in all directions.

• The bad news: That extreme mobility makes it prone to dysfunction and injury—especially as you age or overuse it.

If your shoulder starts acting up, you might experience:

✅ Pain
✅ Limited range of motion
✅ Weakness
✅ Swelling
✅ Numbness/tingling down the arm (if nerves are involved)

What keeps your shoulder from falling apart? Your rotator cuff—a group of four stabilizing muscles:

• Supraspinatus

• Infraspinatus

• Teres minor

• Subscapularis

(Use the acronym “SITS” to remember them and impress your doctor.)

These muscles form a protective "cuff" around your shoulder joint, keeping it stable and allowing smooth movement. But if your rotator cuff is weak, inflamed, or impinged, your shoulder can’t do its job—leading to pain and frustration.

(source)

What Is Shoulder Impingement?

Shoulder impingement occurs when the tendons of your rotator cuff get pinched between your acromion (the bony part of your shoulder) and humerus (arm bone).

It’s the #1 cause of shoulder pain, especially in:

🔹 Overhead athletes (baseball, swimming, etc.)
🔹 People over 50
🔹 Anyone with bad posture or repetitive overhead movement

Common Symptoms:

⚡ Pain when lifting your arm overhead, out to the side, or behind your back
⚡ Pain at night, especially when sleeping on the affected side
⚡ Weakness and reduced range of motion
⚡ Tenderness in the front of the shoulder

Here’s the problem: Impingement creates a vicious cycle.

1️⃣ The pinched rotator cuff tendons get inflamed and swollen.
2️⃣ That swelling reduces space in the joint, worsening impingement.
3️⃣ Pain and dysfunction continue unless you fix the root cause.

And the root cause? Often, it’s poor shoulder blade movement and weak stabilizer muscles.

(source)

Shoulder Blade Function & Thoracic Mobility: The Hidden Culprits

Your shoulder depends on two things to stay pain-free:

1️⃣ Scapular (shoulder blade) control

2️⃣ Thoracic (mid-back) mobility

Here’s why:

🔹 Your shoulder blade must rotate properly when you lift your arm.

Normally, your arm and shoulder blade move at a 2:1 ratio. For every two degrees your arm moves, your shoulder blade moves one.

(source)

If your shoulder blade doesn’t rotate correctly, your rotator cuff gets pinched.

🔹 Your mid-back (thoracic spine) needs to extend.

If you slouch all day, your shoulders roll forward, reducing space for movement.

Try this: Slouch and raise your arms overhead. It’s tough, right? Now sit up tall and do the same. Big difference.

Lack of scapular control + poor thoracic mobility = a recipe for chronic shoulder pain.

(source)

The Muscles Involved in Shoulder Dysfunction

Six key muscles control scapular rotation, ensuring smooth shoulder movement and preventing impingement. These muscles work in two opposing groups:

Upward Rotation:
🔹 Upper Trapezius
🔹 Lower Trapezius
🔹 Serratus Anterior

Downward Rotation:
🔹 Rhomboids
🔹 Levator Scapulae
🔹 Pectoralis Minor

When these muscles work in balance, the shoulder joint moves efficiently without excessive stress on the rotator cuff or acromion. However, shoulder impingement often results from imbalances, particularly in the pec minor, mid/lower trap, and serratus anterior.

• Pec Minor: This small but powerful muscle pulls the shoulder blade downward and forward. It’s frequently tight due to prolonged sitting, driving, and computer work, contributing to poor posture and impingement. Releasing it is crucial for restoring proper shoulder mechanics.

• Mid & Lower Traps: These muscles counteract the pull of the pec minor by drawing the shoulder blades down and back. Strengthening them improves posture, shoulder stability, and reduces impingement.

• Serratus Anterior: Often called the "holy grail" of shoulder health, this muscle secures the shoulder blade against the ribcage, allowing for smooth overhead movement. Weakness here can lead to instability and pain.

Best Exercises for Shoulder Pain Relief

If you’re dealing with shoulder pain, correcting muscle imbalances and improving mobility is the key to long-term relief.

These are my most commonly prescribed exercises for shoulder pain:

Thoracic Spine Mobility:

🟢 Quadruped Thoracic Rotations – Improves rotational mobility and reduces stiffness in the mid-back.

🟢 Thoracic Extension Over Foam Roller – Helps reverse the effects of poor posture and opens up the upper back for better shoulder movement.

Mid-Trap, Low-Trap, & Rhomboid Activation:

🔹 Band Pull Aparts – Strengthens the mid-back and reinforces good posture.

🔹 Prone T/I/W/Ys – Develops strength in the mid-trap, lower trap, and rhomboids for improved shoulder stability.

Serratus Anterior Activation:

🔸 Wall Slides – Reinforces upward rotation of the shoulder blade, reducing impingement risk.

🔸 Push-Up Plus – Strengthens the serratus anterior by adding an extra "push" at the top of a push-up to improve scapular control.

Shoulder Pain Is Complex—But Relief Is Possible

Pain is never simple.

While the issues we’ve covered—poor scapular control, limited thoracic mobility, and muscle imbalances—are some of the most common causes of shoulder pain, not every case fits neatly into this framework. There are many factors at play, from past injuries to structural differences, and not all pain can be solved with the same approach.

That said, if you’re dealing with one of the most common types of shoulder discomfort, the strategies and exercises in this guide should help you start feeling better, moving better, and regaining confidence in your shoulders.

But if you’re still struggling—or want a customized plan that ensures long-term relief—this is where my online fitness coaching stands out.

I don’t just focus on helping you look better. I help you move better, feel better, and stay pain-free while building strength and resilience.

Ready to take the next step toward pain-free progress? Let’s get started today.

Best,

John

P.S. That’s the type of fat loss graph we love to see! Shout out to my online fitness client, Derek - crushing it!!

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