Growth hormone promotes bone and muscle growth. With aging, people lose muscle mass and bone strength, possibly because of decreased levels of growth hormone. People with RA have bone and muscle changes similar to those in older people, perhaps also due to decreased levels of growth hormone. The first part of this study will see if the inflammatory mediators responsible for joint inflammation (warmth, redness, pain, and swelling) in RA are related to the lowered growth hormone levels in this disease. The second part will evaluate the effect of etanercept treatment on muscle mass and bone density, in addition to growth hormone levels.