A significant proportion of COPD subjects experience muscle wasting, which has been associated with increased morbidity, impaired physical functioning, and a poor quality of life. Muscle wasting is associated with reduced muscle strength in COPD subjects. In particular, weakness of peripheral muscles has been reported to play an important role in the reduced functional capacity and impaired exercise performance. The primary objective of this study is to investigate the effect of tesamorelin, in conjunction with exercise training, on lean body mass measured by dual energy x-ray absorptiometry (DXA) scan.