Exercise for patients with Chronic Obstructive Pulmonary Disease (COPD)

Physical exercise has become an essential part of the management of patients with advanced COPD. It has been a common belief that physical exercise, in particular endurance exercise, is difficult to perform for these patients. Scientists of the Horten Centre (University of Zurich) showed in their recent study that patients tolerate interval exercise well and that health state can be improved with this method. The study was published in Annals of Internal Medicine on December 5 2006 (Volume 145:816-825, www.annals.org)

In Switzerland, approximately 400’000 patients suffer from COPD. These patients not only have dyspnea and chronic cough but also markedly reduced exercise capacity limiting their level of daily activities and quality of life. Also, reduced exercise capacity is associated with elevated risk for hospital admissions and early death.

Hence, COPD patients should necessarily incorporate physical activity in their daily life. However, physical activity is often difficult for these patients because they are limited by dyspnea. Milo Puhan, MD, PhD, from the Horten Centre of the University of Zurich and Martin Frey, MD, from the Klinik Barmelweid (Aargau, Switzerland) evaluated a particular form of physical exercise called interval exercise. During exercise sessions of 25 minutes, patients exercise alternatively at high intensity for 20 seconds and at low intensity for 40 seconds. In a randomised trial, the scientists showed that symptoms and exercise capacity improved to a similar degree as with continuous exercise, which is recommended by international guidelines. In turn, interval exercise is better tolerated than continuous exercise as expressed by the significantly lower number of unintended breaks.

Efficient training stimulus
Although patients perform substantially less work with interval exercise compared with continuous exercise, the effect is of similar size. How is this possible? Milo Puhan explains: “The short intervals at very high intensity seem to be an efficient stimulus for the muscles. Such high exercise loads are not possible with continuous exercise because patients are too limited by their dyspnea.”

The study widens the perspective in the non-pharmacological treatment of COPD. In contrast to earlier beliefs, physical exercise is possible for patients with even advanced COPD if a tolerable and effective exercise protocol is chosen. By improving exercise capacity and symptoms, quality of life of these patients is improved substantially.

Contact
PD Dr. med. Milo Puhan, PhD
Horten Centre, University of Zurich
Tel. +41 44 255 8709
eMail: milo.puhan@usz.ch