ABSTRACT
The most common lung disease in adults is chronic
obstructive pulmonary disease (COPD; Jemal et al. 2005),
and for this condition it is clearly established that pulmonary
rehabilitation is effective in improving patient function judged by performance on an exercise test, quality of life,
and indeed in terms of unplanned hospital attendance
(Griffiths et al. 2000; Troosters et al. 2000). The mechanism
of improvement is unknown and, interestingly, is not
confined to those with either good or poor pre-rehabilitation
exercise performance (Singh et al. 2008). There is consensus,
however, that the improvement is not achieved by alteration
in lung function. It is most likely that improvements in
peripheral muscle function are a key element of a successful
rehabilitation program. Peripheral muscle weakness is com-
mon in COPD (Seymour et al. 2010), so this is a plausible
hypothesis.
