Endurance training in patients with chronic obstructive pulmonary disease: A comparison of high versus moderate intensity

Purpose: To create a maximum tolerated 45-minute aerobic training program, for patients with chronic obstructive pulmonary disease (COPD) and to compare its outcomes with those of commonly prescribed moderate exercise. Design: Prospective, randomized trial. Setting: A work physiology laboratory. Patients and Methods: The maximum exercise intensities that 7 COPD patients could sustain for 45 minutes were determined on a bilevel exercise ergometer. The patients then exercised 45 minutes daily, 5 days a week for 6 weeks, working 2.03 +/- 0.4kJ/kg per session. They were matched with 6 COPD patients who pushed an O-2 cart for 45 minutes daily, 5 days a week for 6 weeks, working 1.44 +/- .35kJ/kg per session. Results: A 45 minute maximal regimen was established by alternating I-minute peak exercise at peak ire, levers with 4 minutes at the ventilatory anaerobic threshold or at 40% of peak (V) over dot O-2. Maximal bilevel training significantly decreased dyspnea at rest (p less than or equal to.01) and the blood lactate level during submaximal exercise (p <.001), and increased peak (V) over dot O-2 and total physical work (p <.01), maximum inspiratory and expiratory pressures (p <.01), and grip and forearm strength and endurance (p <.01), The training also increased maximum voluntary ventilation while decreasing the ventilatory equivalent during exercise (p <.001). The O-2 cart pushers significantly improved only on the 12-minute walk(p <.05). Conclusions: A maximally intense anaerobic exercise program can be created for most COPD patients that can significantly improve both skeletal and respiratory muscle strength and endurance as well as dyspnea and physiologic parameters.