Swimmer's Shoulder: What You Should Know

by Stephanie Korso, PT

Swimming is a phenomenal way to improve cardiovascular fitness, burn lots of calories, strengthen muscles and prevent disease. As a non-contact sport, there is little risk for acute and catastrophic injuries, but there is still risk for injury. Prevention, early recognition and early treatment are key to managing swimming injuries and remaining active.

The most common swimming injury is swimmer's shoulder, which refers to any shoulder pain related to swimming. Up to 90% of swimming injuries involve the shoulder, and as many as 73% of swimmers may report shoulder pain during their career. The repetitive nature of swimming contributes to overuse and predisposes swimmers to shoulder injury.

Although swimmer's shoulder can involve any shoulder dysfunction, such as tendinosis or impingement syndrome, shoulder instability is the most common. This is because the same factors that improve swimming performance also contribute to shoulder instability:

Increased Shoulder Range of Motion
Increased shoulder range of motion helps reduce drag and allows for greater stroke length, both of which contribute to increased swimming speed. However, increased range of motion also contributes to increased ligament laxity and increased strain on rotator cuff muscles, which contributes to decreased stability.

Increased Shoulder Adduction and Internal Rotation Strength
Up to 90% of forward propulsion in swimming comes from the upper body. The pectoralis major and latissimus dorsi muscles, responsible for shoulder adduction and internal rotation, are the primary muscles that create the propulsive force needed in swimming. Increased strength in these muscles contributes to increased swimming speed, but it also leads to muscle imbalance and further instability.

Prolonged, Fatiguing Shoulder-Intensive Training
An experienced swimmer knows that swimming involves both shoulder strength and endurance. Training involves long work-outs that fatigue muscles. As rotator cuff and scapular muscles fatigue, shoulder instability increases.

The primary goals in management of swimmer's shoulder are to reduce inflammation, increase stability and return the athlete to full activity as soon as possible. Initially, the athlete will need to modify activity so that no pain is experienced. During this time, the athlete will implement exercises to decrease muscle imbalances, improve rotator cuff and scapular strength, and improve muscle endurance. The athlete may then gradually increase activity as pain decreases. Physical therapy is often helpful not only to guide progressions of strength exercises, but to also improve spine mobility and help release overworked pectoralis major and latissimus dorsi muscles.

As the saying goes, prevention is better than the cure. Therefore, incorporating exercises to strengthen the rotator cuff and scapular muscles into training regimens prior to onset of pain is optimal.

References:
Weldon EJ III, Richardson AB. Upper extremity overuse injuries in swimming. Clinical Sports Med. 2001; 20(3), 423-438.

Weiss Kelly A. Non-contact sports: Running, swimming, and dance - identifying common injuries. Pediatric Annals. 2010; 39(5), 279-285.

Khodaee M, Edelman GT, Spittler J, et al. Medical care for swimmers. Sports Med. 2016; 2(27).