Effectiveness of different types, delivery modes and extensiveness of exercise in patients with breast cancer receiving systemic treatment – A systematic review and meta-analysis

Background: Effects of exercise in patients with breast cancer have been thoroughly investigated. The aim was to explore differences in effects regarding type, delivery mode and extensiveness (e.g. intensity; volume) of the interventions. Methods: We searched for randomised controlled trials including patients with breast cancer receiving systemic treatment, exercise-based interventions, and measures on patient reported- and objectively measured outcomes. Results: Exercise showed significant and moderate effects on the primary outcomes quality of life and physical function, Standardised Mean Difference: 0.52 (95 % CI 0.38–0.65) and 0.52 (95 % CI 0.38–0.66), respectively. Type of exercise had little influence on the effects, however combined aerobic- and resistance exercise seemed superior for increasing physical function, compared to aerobic or resistance exercise. Supervised interventions were superior to partly and unsupervised. Extensiveness of the intervention only influenced physical function. Conclusions: Supervised interventions, more than type or extensiveness of interventions, seem to increase effects.