Men with prostate cancer reduce the risk of death from all causes by 46% if they do moderate exercise, such as walking, for 90 minutes a week. Men who perform vigorous exercise for >3 hours each week lower their overall mortality risk by 49%, suggests a study published in the Journal of Clinical Oncology. In addition, they reduce their risk of death from prostate cancer by 61% compared with men who exercise <1 hour each week. Outcomes are best for men who exercised routinely before diagnosis and continue to do so.