The Best Exercises for Your Shoulders (They're Not the Ones You Think)

Everyone asks me what they should be doing at the gym to protect their shoulders. Here's the honest answer, and it probably looks nothing like your current routine.

The muscles that actually keep your shoulder healthy aren't the glamorous ones. They're not the ones that fill out a t-shirt. They're three groups most people completely ignore: the rotator cuff, the serratus anterior, and the lower trapezius.

Understanding why these muscles matter (and how to train them) is the foundation of long-term shoulder health. Here's what the evidence says.

Why These Muscles? The Short Anatomy Lesson.

Your shoulder is the most mobile joint in the body — which means it's also the least inherently stable. Unlike the hip, which has a deep bony socket for support, your shoulder's ball sits in a socket about the size and depth of a shallow teacup. The muscles around it are what keep it centered, functioning, and pain-free.

The problem is that most gym programs train the muscles you can see in the mirror while systematically neglecting the muscles that do the stabilizing work behind the scenes. Over time, that imbalance accumulates, and it shows up in my office as impingement, rotator cuff tears, and chronic shoulder pain.

Research consistently shows that patients with shoulder pain have overactive upper trapezius muscles and underactive lower trapezius and serratus anterior muscles. Training to correct that imbalance (not simply 'strengthening the shoulder' in general) is what the evidence supports.

The Three Exercises That Actually Matter

1. Side-Lying External Rotation

Target muscle: Infraspinatus and teres minor (the posterior rotator cuff)

This is the most important exercise on this list, and it's the one that looks the least impressive. You lie on your side, hold a light dumbbell, and rotate your forearm upward. That's it. If you're doing it with more than five or six pounds and you haven't been training it for months, you're probably cheating the movement.

Here's why it matters: the infraspinatus and teres minor are the muscles responsible for keeping the head of your humerus — your upper arm bone — centered in the socket every time you move your arm. When they're weak, the ball migrates upward with shoulder elevation, compressing the tendons against the overlying bone. That's impingement. That's how rotator cuff tears start.

THE SCIENCE: EMG studies show that side-lying external rotation produces the highest activation of the infraspinatus and teres minor compared to other common shoulder exercises — with the added benefit of minimal joint stress. It is the most efficient way to target these muscles.

HOW TO DO IT

Position: Lie on your side. The arm being trained is on top. Place a small folded towel between your elbow and your ribs to keep the upper arm neutral.

Movement: With your elbow bent to 90°, slowly rotate your forearm upward toward the ceiling. Pause at the top. Lower under control. Do not let your elbow drift away from your body.

Weight: 2–5 lbs to start. This should be challenging at higher reps — if it isn't, increase weight gradually.

Sets & Reps: 3 sets of 15 repetitions per side.

Frequency: 2–3 times per week, with at least one day of rest between sessions.

Common mistake: Letting the shoulder roll forward and turning this into a chest movement. Keep the shoulder blade gently set back and down throughout.

2. The Push-Up Plus

Target muscle: Serratus anterior (the scapular stabilizer)

Your serratus anterior is a flat muscle that wraps around the outer surface of your ribcage and attaches to the inner border of your shoulder blade. Its job is to hold the shoulder blade flat against the chest wall and rotate it upward when you raise your arm. When it's weak, the scapula wings outward — and when the scapula wings, your shoulder mechanics fall apart.

The push-up plus is a standard push-up with one additional movement at the top: after you've pushed all the way up, you round your upper back and push your shoulder blades further apart, as if you're trying to make yourself slightly taller. That extra few centimeters of motion is where the serratus does its work.

No weight required. No gym required. And yet this exercise consistently outperforms more complex movements for serratus activation.

THE SCIENCE: A systematic review and meta-analysis of push-up variants confirmed that the push-up plus produces the highest serratus anterior EMG activation of any common push-up variation. Separate research found the serratus generates 50–80% of its maximal contraction during this movement — comparable to clinical rehabilitation benchmarks.

HOW TO DO IT

Position: Standard push-up position — hands shoulder-width apart, body in a straight line. Beginners can start on the knees.

Movement: Lower to the bottom of the push-up, press all the way up, then at the very top, push your shoulder blades apart and round your upper back slightly upward. Hold for 1 second. Lower with control.

Weight: Bodyweight only.

Sets & Reps: 3 sets of 10–15 repetitions.

Frequency: 2–3 times per week.

Progression: Once this becomes easy in the standard position, try elevating your feet slightly — research shows this increases serratus activation further.

Common mistake: Skipping the 'plus' phase entirely and treating this as a regular push-up. The extra reach at the top is the whole point. Without it, you're just doing a push-up.

3. Prone Y Raises

Target muscle: Lower trapezius

The lower trapezius is probably the most consistently neglected muscle in the shoulder complex, and its weakness is one of the most common findings in patients I see with shoulder pain. It runs diagonally from your lower thoracic spine up to the outer edge of your shoulder blade, and its job is to depress and posteriorly tilt the scapula. Essentially, its job is to pull your shoulder blade down and back as your arm rises overhead.

When the lower trap is weak, the upper trapezius compensates. Your shoulder shrugs up with every arm movement. The subacromial space narrows and impingement follows. This pattern is observed in shoulder patients so consistently that correcting this imbalance has become a cornerstone of shoulder rehabilitation.

Prone Y raises address this directly. You lie face down, extend your arms in a Y shape at roughly 45 degrees from your midline, thumbs pointing to the ceiling, and lift slowly. Two to five pounds will humble most people. That's normal... these muscles are almost universally undertrained.

THE SCIENCE: EMG studies demonstrate that prone shoulder elevation with external rotation in the Y position elicits near-maximal lower trapezius activation while minimizing upper trapezius recruitment, making it the most targeted exercise available for this muscle. A systematic review confirmed that prone-position exercises are the most effective exercises for optimal lower-to-upper trapezius activation ratios.

HOW TO DO IT

Position: Lie face down on a mat, a bed, or a bench. Arms extended above your head in a Y shape — approximately 45° from the midline. Thumbs pointing to the ceiling.

Movement: Keeping your arms straight, lift them slowly off the surface — no more than a few inches. Think about pulling your shoulder blades down and toward your spine rather than just lifting your arms. Pause at the top for 1–2 seconds. Lower with complete control.

Weight: 2–5 lbs. Start with no weight until you can feel the right muscles activating. Heavier is not better here.

Sets & Reps: 3 sets of 12–15 repetitions.

Frequency: 2–3 times per week.

Common mistake: Shrugging the shoulder upward during the lift, causes the upper trapezius to take over. If your shoulder rises toward your ear during this movement, lower the weight and focus on the sensation of the shoulder blade moving down and back, not the arm moving up.

The Honest Truth About Popular Exercises

Now for the part of this post that will be controversial in some gym circles.

The bench press and the overhead press are staples of almost every gym program. They build the pectoralis major, the anterior deltoid, and the triceps, which are the muscles that look impressive and contribute to upper body strength. I'm not here to tell you never to do them.

But I am here to tell you that they are not ideal exercises for long-term shoulder health, and that the way most people perform them works against the muscular balance we've been building above.

Here's what the evidence shows: biomechanical research using musculoskeletal modeling has found that wide grip bench pressing with high shoulder abduction angles is theorized to reduce the subacromial space and increase acromioclavicular joint compression forces.

I want to be clear about what the evidence is and isn't: most of this is based on biomechanical modeling and clinical expert opinion rather than large randomized trials definitively proving harm. While the concern is mechanistically well-grounded, it has not yet been demonstrated at the highest level of evidence. With that said, in my clinical experience, the pattern is consistent.

If you enjoy bench pressing and overhead pressing, you don't necessarily have to stop, but they should never be the foundation of your shoulder training, and they should always be paired with the exercises described above. A good ratio to work towards: for every pressing movement, perform at least one pulling or posterior shoulder exercise.

Your Starting Program

If you want to begin implementing these exercises, here is a simple, evidence-consistent starting framework:

Frequency: 2–3 sessions per week, with at least one rest day between sessions.

Duration: Each session takes approximately 15–20 minutes. These exercises work well as a warm-up before upper body training or as a standalone shoulder-health routine.

• Side-lying external rotation: 3 × 15 each side (2–5 lbs)

• Push-up plus: 3 × 10–15 (bodyweight)

• Prone Y raises: 3 × 12–15 (2–5 lbs)

Progress conservatively. These muscles are typically undertrained and will respond quickly in the first 4–6 weeks. Resist the urge to load heavily. Control and isolation of the right muscles matters far more than weight here.

Expect some initial soreness in places you may not have felt before like the back of the shoulder, the upper outer ribcage, and the mid-back between the shoulder blades. That's normal.

An Important Note

These exercises are appropriate for most healthy adults looking to maintain shoulder function and reduce injury risk. If you have a known rotator cuff tear, shoulder instability, a history of shoulder surgery, or are currently experiencing shoulder pain, do not start a new exercise program without first speaking with your physician or physical therapist. Some of these movements may be contraindicated depending on your specific condition, and the appropriate exercises for your situation may differ from what is described here.

When in doubt, get evaluated. The information in this post is educational and it is not a substitute for an individualized assessment.

The Bottom Line

Your shoulders can last a lifetime if you train the right muscles. These three evidence-based exercises may be unglamorous, but they require minimal equipment, minimal time, and can be done at home.

Call to book an appointment:

646-665-6784

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About the Author

C. Lucas Myerson, MD – Orthopedic surgeon specializing in shoulder and elbow surgery.

Disclaimer

This content is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before beginning any new exercise program.

Sources

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• Huang TS, Du WY, et al. The impact of subacromial impingement syndrome on muscle activity patterns of the shoulder complex: a systematic review of electromyographic studies. BMC Musculoskelet Disord. 2010;11:45.

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