Resistance training reduces disability in prostate cancer survivors on androgen deprivation therapy: evidence from a randomized controlled trial

Objectives: To investigate whether functionally based resistance exercise could improve strength, physical function, and disability among prostate cancer survivors (PCS) on androgen deprivation therapy (ADT); and to explore potential mediators of changes in outcomes from exercise.

Design: Randomized controlled trial.

Setting: Academic medical center.

Participants: PCS (N=51; mean age, 70.2y) on ADT.

Intervention: PCS were randomized to moderate to vigorous intensity resistance training or stretching (placebo control) for 1 year.

Main outcome measures: Maximal leg press and bench press strength, objective and self-reported physical function, and self-reported disability. Hierarchical linear modeling was used to test for significant group × time differences adjusting for covariates.

Results: Retention in the study was 84%, and median attendance to supervised classes was 84% in the resistance group. No study-related injuries occurred. Maximal leg strength (P=.032) and bench press strength (P=.027) were improved after 1 year of resistance training, whereas little change occurred from stretching. Self-reported physical function improved with resistance training, whereas decreases occurred from stretching (P=.016). Disability lessened more with resistance training than stretching (P=.018). One-year change in leg press strength mediated the relation between groups (resistance or stretching) and 1-year change in self-reported disability (P<.05).

Conclusions: One year of resistance training improved muscle strength in androgen-deprived PCS. Strengthening muscles using functional movement patterns may be an important feature of exercise programs designed to improve perceptions of physical function and disability. Findings from this study contribute to the mounting evidence that exercise should become a routine part of clinical care in older men with advanced prostate cancer.