Attention to principles of exercise training: a review of exercise studies for survivors of cancers other than breast.

Objectives: Randomised controlled trials (RCTs) can evaluate how well a particular exercise programme reduces cancer treatment-related side effects. Adequate design and reporting of the exercise prescription employed in RCTs is central to interpreting study findings and translating effective interventions into practice. Our previous review on the quality and reporting of exercise prescriptions in RCTs in breast cancer survivors revealed several inadequacies. This review similarly evaluates exercise prescriptions used in RCTs in patients with cancers other than the breast.

Methods: The literature was searched for RCTs in persons diagnosed with a cancer other than breast. Data were extracted to evaluate the attention to the principles of exercise training in the study design and the reporting of and adherence to the exercise prescription used for the intervention.

Results: Of the 33 studies reviewed, none attended to all of the exercise training principles. Specificity was applied by 89%, progression by 26%, overload by 37%, initial values by 26%, diminishing returns by 9% and reversibility by 3%. Only 2 of 33 studies (6%) reported both the exercise prescription in full and adherence to each individual component of the prescription.

Conclusions: Application of the principles of training in exercise RCTs of non-breast cancer survivors was incomplete and inconsistent. Given these observations, interpretation of findings from the reviewed studies should consider potential shortcomings in intervention design. Though the prescribed exercise programme was often described, adherence to the entire prescription was rarely reported providing a less accurate picture of dose-response and challenges in translating programmes to community settings.