Swimmer’s Shoulder: Causes, Prevention, and Physiotherapy Treatment

If you swim laps regularly, whether at a Surrey recreation centre pool or as part of a masters or competitive club, you have probably felt it at some point: a nagging ache deep in the front or top of your shoulder that shows up somewhere around the fiftieth lap and lingers long after you have toweled off.

Known as swimmer’s shoulder, this ranks among the sport’s most frequent overuse injuries. Research on competitive swimmers has found that shoulder pain affects the large majority of athletes at some point in their career, with some studies putting the figure as high as nine out of ten. At Surrey 152 St Fleetwood Physiotherapy & Sports Injury Clinic, swimmer’s shoulder is one of the overhead-athlete injuries we see regularly, right alongside tennis elbow and ACL injuries.

What Is Swimmer’s Shoulder?

Swimmer’s shoulder is not one single diagnosis. It is an umbrella term for a group of related problems that tend to show up together in swimmers, most often subacromial pain syndrome and rotator cuff tendinopathy.

You may have heard this kind of pain described as shoulder impingement, the idea that a tendon gets physically pinched as it passes under the tip of the shoulder blade with every stroke. That explanation has fallen out of favour in recent years. Imaging studies have repeatedly shown that this same movement pattern shows up just as often in people with no shoulder pain at all, which means pinching alone cannot explain why some shoulders hurt and others do not. Instead, we now talk about subacromial pain syndrome, a broader term for pain coming from that region of the shoulder that reflects what is actually happening: an irritated tendon and surrounding tissue that has been asked to handle more load than it currently has the capacity for.

That shift in language points you toward a more useful question. Rather than asking what is pinching, it is more helpful to ask why the tendon became irritated in the first place. Training volume, stroke technique, recovery, sleep, and how gradually your shoulder was prepared for the demands you placed on it all factor into how much load that tendon can tolerate before symptoms show up.

Your rotator cuff is a group of four small muscles and tendons that hold your upper arm bone snugly in the shoulder socket while your larger, more powerful muscles do the work of pulling you through the water. When those tendons are asked to stabilize the joint through tens of thousands of repetitions per week without enough capacity or recovery behind them, they can start to break down faster than they repair. That is the rotator cuff tendinopathy piece of the picture, and it is closely tied to subacromial pain syndrome rather than a separate, unrelated problem.

There is an added wrinkle for swimmers specifically. Many swimmers have naturally looser, more mobile shoulder joints, which helps with the long reach and rotation a good stroke requires. That same mobility means the rotator cuff has to work harder to keep the joint controlled and centred, which is part of why swimmers are so prone to this cluster of injuries in the first place.

What Causes Swimmer’s Shoulder?

Swimmer’s shoulder rarely comes from one bad session. It builds gradually from a combination of factors, including:

• Training volume that climbs too quickly. A sudden jump in yardage, added sets, or a return to training after time off gives the shoulder no chance to adapt. Tendons build capacity gradually, so a spike in load without enough recovery between sessions is one of the most reliable ways to trigger symptoms, even when your technique and strength have not changed at all.
• Stroke technique. Poor body rotation, crossing the arm over the midline on entry, or dropping the elbow during the pull can all increase stress on the rotator cuff and the front of the shoulder. These patterns change the angle your rotator cuff has to control the arm from on every single stroke, and that small extra demand adds up quickly across a full set.
• Muscle imbalances. Swimmers often develop strong, tight chest and lat muscles from the pulling phase of the stroke, while the smaller scapular stabilizers and rotator cuff muscles that should balance them out get comparatively weaker. Over time, the muscles meant to keep your shoulder blade and joint well positioned end up outmatched by the muscles doing the pulling, so they fatigue long before the set is finished.
• Underlying shoulder laxity. The same mobility that makes a strong stroke possible can leave the joint less stable if the surrounding muscles are not strong enough to compensate. When strength has not kept pace with that mobility, the ball of the joint can shift slightly within the socket during the stroke, asking the rotator cuff to work harder to keep things centred.
• One-sided breathing patterns. Consistently breathing to the same side can create rotation and loading imbalances between your left and right shoulder over a season. Your total yardage might look even on paper, but one shoulder can end up handling noticeably more rotational stress than the other.
• Equipment overuse. Hand paddles and pull buoys add resistance that increases shoulder load, and relying on them too heavily too often can outpace what your shoulder is ready for. Because paddles increase the surface area your hand pulls against, the same number of sets can represent a meaningfully higher load than swimming without them.

Preventing Swimmer’s Shoulder

The good news is that most of these contributing factors are things you can actually manage. A few habits go a long way:

• Build training volume gradually, especially after a break, rather than jumping straight back into full sets.
• Work dryland scapular and rotator cuff strengthening into your weekly routine, not just time in the water.
• Ask a coach to periodically check your stroke technique, particularly your body rotation and elbow position during the pull.
• Alternate your breathing side when you can, rather than always breathing to the same side.
• Pay attention to shoulder fatigue or soreness that shows up at a predictable point in your set. Catching it early is far easier than treating it once it becomes a persistent, nagging pain.

How Physiotherapy Helps With Swimmer’s Shoulder

Swimmer’s shoulder responds well to physiotherapy, and in most cases you do not need to stay out of the pool entirely while you recover. At Surrey 152 St (Fleetwood) Physiotherapy & Sports Injury Clinic, a typical plan includes:

1. A thorough assessment. We look at your shoulder and scapular strength, joint mobility, and posture, and we ask about your training volume, stroke, and any recent changes to your program to understand what is driving your symptoms.
2. Hands-on treatment. Soft tissue therapy, joint mobilizations, or IMS can help reduce irritation and restore normal movement through the shoulder and thoracic spine.
3. Progressive rotator cuff and scapular strengthening. This usually starts with isometric and light band work for the rotator cuff, along with scapular stabilization exercises, then builds toward more demanding strength and control work as your symptoms settle, since a stronger rotator cuff is what ultimately keeps a mobile shoulder centred and controlled.
4. Stroke and load management guidance. We help you figure out how much volume, paddle use, and intensity your shoulder can currently handle, and how to build back up without repeating the same overload pattern.
5. A gradual return to full training. Rather than a strict stop to swimming, we build a plan that keeps you moving in the water while your shoulder regains the strength to keep up with your training demands.

A Few Exercises We Often Include

Every program is built around your specific assessment findings, but three exercises come up often in swimmer’s shoulder rehab:

• PNF D1 and D2 patterns with a resistance band. These diagonal, multi-plane movement patterns closely mirror the combination of rotation, reach, and elevation your shoulder handles during a stroke, training it to control all three at once rather than one at a time.
• Prone shoulder CARs, or controlled articular rotations. Lying face down, you slowly circle the arm through its full pain free range in a controlled, deliberate way. This builds strength and body awareness through the outer edges of your shoulder’s mobility, which matters given how much range swimming asks of that joint.
• General external rotation strengthening. Simple side-lying or band-resisted external rotation work targets the rotator cuff directly, building the capacity it needs to keep the joint centred and controlled through thousands of repeated overhead strokes.

An Encouraging Takeaway

Swimmer’s shoulder is common among swimmers of every level, from weekend lap swimmers to competitive club athletes, and it responds well to the right combination of strengthening, technique adjustments, and load management. You do not have to choose between your training goals and a pain free shoulder.

If shoulder pain has been creeping into your swim sets, our team at Surrey 152 St Fleetwood Physiotherapy & Sports Injury Clinic would be glad to take a look. Reach out to book an assessment and let’s get your stroke, and your shoulder, back on track.