Abstract
When exercise is the drug: can activity levels really be used to treat prostate cancer?

There is sufficient evidence demonstrating the favourable effects of exercise on symptom control and quality of life in prostate cancer. A gap exists in our knowledge regarding the true efficacy of exercise on hard clinical outcomes i.e. prostate cancer specific mortality and overall survival.

Epidemiological studies do however suggest that exercise may improve survival given the lower mortality rate seen in more active men post prostate cancer treatment, this has yet to be definitely demonstrated in a clinical trial.

The INTERVAL study, a global study of exercise in advanced prostate cancer is currently underway to attempt to answer this question. Although exercise is not a pharmacologic intervention, when prescribed appropriately, it does confer drug like effects that cause changes to the individual’s homeostasis, either as a targeted therapy (exerting its own anticancer effects independent of other therapies) or as a synergistic medicine (increasing effectiveness of therapies applied concurrently).

It is necessary to use an ‘exercise as medicine’ approach, individually prescribing and designing the intervention utilising the principles of training (individualised, specificity, overload, rest and recovery) to improve survival via inflammatory, hormonal, and/or energy metabolism pathways. There are however issues that need to be addressed e.g. the cost of conducting complex intervention studies, the practicality of delivering prescribed exercise in the current NHS setting, and of course, how we get people to change their behaviour and actually move more.