Competitive swimmers are affected by several musculoskeletal and medical complaints that are unique to the sport. 'Swimmer's shoulder,' the most common overuse injury, is usually caused by some combination of impingement, rotator cuff tendinopathy, scapular dyskinesis, and instability. The condition may be treated with training modifications, stroke error correction, and strengthening exercises targeting the rotator cuff, scapular stabilizers, and core. Implementation of prevention programs to reduce the prevalence of shoulder pathology is crucial. Knee pain usually results from the breaststroke kick in swimmers, and the 'egg beater' kick in water polo players and synchronized swimmers. Lumbar back pain also is common in aquatics athletes. Among the medical conditions of particular importance in swimmers are exercise-induced bronchoconstriction, respiratory illnesses, and ear problems. Participants in other aquatics sports (water polo, diving, synchronized swimming, and open water swimming) may experience medical ailments specific to the sport.