Most people think shoulder pain starts in the shoulder itself. But according to Jeff Cavaliere, a physical therapist who served as head physical therapist and assistant strength coach for the New York Mets, the real problem often comes from a lack of mobility and control in the shoulder blades.

"The shoulder is only as good as the scapula that supports it," Cavaliere says. "If your shoulder blades can't move the way they need to, your shoulder joint is going to be forced to compensate. And eventually, that compensation can turn into stiffness, discomfort, and dysfunction."

Cavaliere, who holds a Master of Science in Physical Therapy and a Bachelor's in Physioneurobiology from the University of Connecticut Storrs, and is a certified Strength and Conditioning Specialist, shared a specific shoulder mobility exercise called the Angel and Devil. He says it is a beginner-friendly way to improve scapular movement, shoulder rotation, and overhead range of motion.

The exercise looks simple, but the key is paying attention to hand position. "Your hands are a reflection of what is happening inside the shoulder joint," Cavaliere explains. "As you move through the exercise, you want to make sure you are rotating through the shoulder and not just swinging the arms around without control."

He recommends performing 8 to 10 reps, 2 to 3 times per week. That cadence, he claims, can start to unlock shoulder mobility, improve scapular movement, and restore range of motion that may have been lost for years.

"If your shoulders feel stiff, tight, achy, or restricted, this is one of the best places to start," Cavaliere says.

The Angel and Devil is not a new exercise in physical therapy circles, but Cavaliere's background gives it weight. He worked directly with Major League Baseball pitchers, athletes who place extreme demands on their shoulders. Rotator cuff and labrum injuries are common in that population, and scapular control is often the foundation of shoulder health in throwing athletes.

Cavaliere's broader message is that shoulder pain is often a downstream consequence of poor blade mechanics. When the shoulder blade can't glide properly across the rib cage, the ball-and-socket joint has to pick up the slack. Over time, that extra load irritates the rotator cuff tendons, pinches the bursa, or inflames the joint capsule.

A standard doctor visit might result in a prescription for anti-inflammatories or a referral for physical therapy that focuses on the shoulder joint itself. But if the scapula is the root cause, treating only the joint may provide temporary relief without fixing the underlying problem. That is why Cavaliere advocates for exercises that retrain the shoulder blade before loading the shoulder.

The Angel and Devil exercise, if done correctly, teaches the body to separate shoulder movement from shoulder blade movement. It also encourages external rotation of the humerus, which is often lost in people who spend hours at desks or hunched over phones. That loss of rotation is one reason overhead reaches become painful.

Cavaliere also offers a free shoulder workout at athleanx.com/bouldershoulders for people who want to progress after improving their range of motion. But the first step, he emphasizes, is getting the blade to move.

For readers who have been told they have tight shoulders, impingement, or general stiffness, trying the Angel and Devil for a few weeks is a low-risk intervention. No equipment is needed. The rep count is low. The time commitment is minimal. And if Cavaliere's experience with pro athletes is any guide, the payoff can be significant.

Shoulder pain is one of the most common complaints in fitness and everyday life. The typical advice is to stretch the front of the shoulder and strengthen the rear. But without fixing scapular control first, those exercises may only reinforce compensation patterns.

Cavaliere's advice flips the standard approach on its head: before you strengthen the shoulder, make sure the blade can move. And the Angel and Devil is a simple, replicable way to test and train that movement.

"When your shoulders start feeling better and you're ready to build them up without the aches and pains, go to athleanx.com/bouldershoulders for a free shoulder workout I put together for you," Cavaliere says.

For people who have struggled with chronic shoulder issues, that may be the most practical advice they get all year.

Note: This article is based on information provided by Jeff Cavaliere, MSPT, CSCS, founder of AthleanX. The claims about the exercise's effectiveness are made by Cavaliere and have not been independently verified by SysCall News. Always consult a qualified healthcare professional before starting a new exercise program, especially if you have an existing injury.