One-Legged Exercise Improves Lung Function in COPD
Switching legs on stationary cycle increases peak oxygen uptake because it reduces total metabolic demand
THURSDAY, Feb. 7 (HealthDay News) -- In patients with stable chronic obstructive pulmonary disease (COPD), one-legged stationary cycle exercise training increases aerobic capacity more than conventional two-legged training, researchers report in the February issue of the journal Chest.
Thomas E. Dolmage, of the West Park Healthcare Centre in Toronto, Ontario, Canada, and a colleague studied 18 patients who exercised on a stationary cycle for 30 minutes three days a week for seven weeks. Half of the subjects engaged in two-legged training, and half used one leg for the first 15 minutes and the other leg for the remaining 15 minutes.
Compared to two-legged training, the researchers found that one-legged training was associated with a greater mean increase in peak oxygen uptake (0.189 L/min versus 0.006 L/min). They also found that subjects in the one-legged exercise group had greater peak ventilation (4.4 L/min), and a lower submaximal heart rate and ventilation. The researchers credited a reduction in total metabolic demand for the improved aerobic capacity observed in the one-legged exercise group and suggested that such training enhances the adaptive response of peripheral muscle.
"A large prospective clinical trial will better characterize the ideal candidate and provide a sample size sufficient for this method of training to be assessed using more variable outcomes such as constant power exercise and health-related quality of life," the authors write. "Muscle-specific training should be considered in conjunction with other approaches that improve exercise capacity in patients with chronic respiratory conditions."