Swimmer's Shoulder: Why Swimmers Develop Shoulder Pain and How to Manage It

An Umbrella Term, Not a Single Diagnosis

“Swimmer’s shoulder” is a long-standing label for shoulder pain in people who swim, rather than a specific diagnosis. The pain may arise from the rotator cuff tendons, the biceps tendon, the joint capsule or the tissues around the shoulder blade, and the neck and upper back can contribute as well. Swimming involves a very large number of repetitive overhead strokes, so the shoulder is exposed to a high cumulative workload even when each individual stroke is light.

Because the label covers several possible sources, the more useful clinical question is usually not whether this is swimmer’s shoulder, but which tissues are irritated and what has changed in the load placed on them.

What the Research Says About Risk Factors

Systematic reviews of risk factors are more cautious than popular advice might suggest. A review of 22 studies of competitive swimmers assessed 80 variables and found no strong evidence for or against an association between any of them and shoulder pain or injury. Moderate evidence supported an association with competitive level and with shoulder muscle recruitment patterns, such as increased serratus anterior activity, while moderate evidence opposed an association with range of motion, training frequency, specialty stroke, sex and age. The highest quality study in that review suggested that a high acute-to-chronic workload ratio and reduced posterior shoulder strength endurance were associated with injury (McKenzie et al., 2023).

An earlier critical review reached a broadly similar conclusion: no risk factor had a high level of certainty, while joint laxity or instability, internal and external rotation, a previous history of shoulder pain or injury, and competitive level were rated as moderate (Hill et al., 2015). Range of motion illustrates the uncertainty, because it appears among the moderate-certainty factors in the earlier review, whereas the later review found moderate evidence against an association.

Managing It Without Chasing a Single Cause

Since no single factor explains swimmer’s shoulder, management generally focuses on the individual swimmer rather than a template. The workload finding is practically useful: a sudden rise in swimming volume or intensity, such as after a break or at the start of a new training block, is a plausible point at which irritation develops, so adjusting and then gradually rebuilding load is usually more productive than complete rest. Strength and endurance of the shoulder blade and rotator cuff muscles, along with trunk control, are commonly addressed, in keeping with the posterior shoulder endurance finding, although the reviews above describe risk factors and do not show that any single exercise program prevents or resolves the problem.

Stroke technique, breathing pattern and the structure of the training week are often best reviewed together with the coach. Pain that wakes the swimmer at night, new weakness, pins and needles, or a sense of the shoulder slipping warrants an assessment rather than waiting it out, as these features can point to something other than load-related irritation, including the neck.