RESUMO
AIMS AND OBJECTIVES: To examine research findings regarding predictors of adherence to exercise programmes in cancer populations. BACKGROUND: Cancer patients are advised to participate in daily exercise. Whether they comply with the recommendations for physical activity or not remains unclear. DESIGN: A systematic review and meta-analysis. METHODS: Empirical articles published in English between 1995 and 2011 were searched in electronic databases and in reference lists, using the search terms 'adherence', 'predictors', 'exercise', and 'cancer' in varying combinations. Twelve of 541 screened abstracts met the inclusion criteria. The included studies' eligibility considering predictors of exercise adherence were reviewed. A quality assessment process evaluating the studies methodological quality was performed. Eight of the reviewed studies were considered eligible for a meta-analysis involving Pearson's r correlations. RESULTS: Exercise stage of change, derived from the transtheoretical model of behaviour change (TTM) was found to be statistically significant and a strong predictor of exercise adherence. In addition, the theory of planned behaviour (TPB) construct; intention to engage in a health-changing behaviour and perceived behavioural control, demonstrated significant correlations with exercise adherence. CONCLUSIONS: The review identified that both the TPB and the TTM frameworks include aspects that predicts exercise adherence in cancer patients, and thus contributes to the understanding of motivational factors of change in exercise behaviour in cancer populations. However, the strengths of predictions were relatively weak. More research is needed to identify predictors of greater importance. RELEVANCE TO CLINICAL PRACTICE: Surveying the patients' readiness and intention to initiate and maintain exercise levels, as well as tailoring exercise programmes to individual needs may be important for nurses in order to help patients meet exercise guidelines and stay active.