Aerobic and strength training in patients with chronic obstructive pulmonary disease

The purpose of this study was to evaluate whether strength training Is a us eful addition to aerobic training in patients with chronic obstructive pulm onary disease (COPD). Forty-five patients with moderate to severe COPD were randomized to 12 wk of aerobic training alone (AERO) or combined with stre ngth training (AERO + ST). The AERO regimen consisted of three weekly 30-mi n exercise sessions on a calibrated ergocycle, and the ST regimen included three series of eight to 10 repetitions of four weight lifting exercises. M easurements of peripheral muscle strength, thigh muscle cross-sectional are a (MCSA) by computed tomographic scanning, maximal exercise capacity, B-min walking distance (6MWD), and quality of life with the chronic respiratory questionnaire were obtained at baseline and after training. Thirty-six pati ents completed the program and constituted the study group. The strength of the quadriceps femoris increased significantly in both groups (p < 0.05), but the improvement was greater In the AERO + ST group (20 +/- 12% versus 8 +/- 10% [mean +/- SD] in the AERO group, p < 0.005). The thigh MCSA and st rength of the pectoralis major muscle increased in the AERO + ST group by 8 +/- 13% and 15 +/- 9%, respectively (p < 0.001), but not In the AERO group (3 +/- 6% and 2 +/- 10%, respectively, p > 0.05), These changes were signi ficantly different in the two study groups (p < 0.01). The increase in stre ngth of the latissimus dorsi muscle after training was modest and of simila r magnitude for both groups. The changes in peak exercise work rate, (6MWD, and quality of life were comparable in the two groups. In conclusion, the addition of strength training to aerobic training In patients, with COPD is associated with significantly greater Increases In muscle strength and mas s, but does not provide additional improvement in exercise capacity or qual ity of life.