One step beyond, does rehabilitation influence physical activity?

Abstract

The measurement of physical activity has become a ‘hot topic’ in the field of pulmonary rehabilitation, as reflected in the systematic review in this issue. The assessment of physical activity is not new however, and there is an accumulating literature in chronic obstructive pulmonary disease (COPD). The level of activity in COPD seems particularly low in comparison with other significant long-term condition, a comparative review of physical activity revealed that activity for individuals was almost half that of individuals with coronary heart disease or arthritis. More recently Watz et al. described the falling levels of activity associated with increasing disease severity. This interest in physical activity was consolidated by the data obtained from the interaction between physical activity and hospital admissions reported from the Copenhagen Heart Study, although at this time the physical activity was described with data from a questionnaire. More specifically high levels of physical activity seem to protect against subsequent readmissions for COPD, the authors of this article suggested that individuals needed to accumulate 60 min of walking a day to reduce the risk of readmission. Pulmonary rehabilitation would seem the ideal intervention to improve physical activity; supporting behaviour change to enhance physical activity is an implicit aim of the service. It has often been assumed that a meaningful change in exercise tolerance after completing a course of rehabilitation will translate into a significant improvement in physical activity. Until fairly recently it has been difficult to objectively test this assumption, but with the commercial development of activity monitors and increased availability of pedometers some authors have tested this hypothesis. The systematic review aimed to evaluate the impact of exercise training upon physical activity. There were no randomised controlled trials (RCTs), this is perhaps not surprising as the monitors are a fairly recent addition to the repertoire of outcome measures and to conduct an RCT where the control group is no intervention would now be considered unethical. Two RCTs were identified; one study explored the relative value of two different exercise regimes delivered within a rehabilitation programme, one arm being conventional rehabilitation. The second, again used conventional rehabilitation as the control arm, but this time compared the standard programme with the addition of a physical activity counselling programme. There were an additional five observational studies included, all were reasonably small sample sizes, with the exception of the recent study by Steele et al. Overall there was a favourable increase in physical activity observed after a course of rehabilitation but this was felt to be small. There are probably a number of reasons to account for this, most obviously that rehabilitation genuinely failed to provoke a significant increase in physical activity. Changes in domestic activity require a supported and structured approach to supervised and home-based exercise and behaviour techniques should be employed to support increased activity during and after a course of rehabilitation. Rehabilitation practitioners have probably been guilty of not pursuing this aspect of rehabilitation as rigorously as might be required to support behaviour change. The authors of this review suggest that a longer course of rehabilitation might be needed to develop these strategies and reinforce behaviour change.