Exercise, Immunity, and Susceptibility to Infection
A J-Shaped Relationship?

It has been widely supposed that regular moderate exercise boosts immunity but that intense training reduces it. A careful look at the literature reveals some evidence for this proposed J-shaped relationship, but several factors cast doubt on it. Nonetheless, practical measures to reduce the risk of infection are advisable for people engaging in rigorous training and competition.

Roy J. Shephard, MD, PhD, DPE; Pang N. Shek, PhD

Injuries to the Glenoid Labrum
A Diagnostic and Treatment Challenge

Poorly localized pain in the shoulder may be a sign of injury to the glenoid labrum, a ring of fibrous tissue that overlies the rim of the glenoid cavity. The function of this structure is not yet fully understood, but it is important in maintaining shoulder stability and is vulnerable to injury in throwing and other overhead activities.

David B. Richards, MD

Elbow Injuries in Young Baseball Players

Pitching is tough on elbows of all ages, but it's especially hazardous for skeletally immature players because injuries often threaten the growth plate of the elbow. Besides covering diagnosis and treatment, the authors give prevention specifics on pitching volume and age guidelines for learning different pitches.

James A. Whiteside, MD; James R. Andrews, MD; Glenn S. Fleisig, PhD

Proximal Biceps Tendon Rupture
Primarily an Injury of Middle Age

A 51-year-old man with a bulging deformity of his left upper arm told of having felt a 'pop' in the arm while rock climbing. His case serves as a good example of the clinical presentation, diagnosis, and treatment of rupture of the proximal biceps tendon, an injury that is often associated with rotator cuff tendinitis.

Amy N. Carter, MD; Steven M. Erickson, MD