LOS ANGELES, Oct. 29 (UPI) -- Prostate cancer patients are not routinely advised to exercise, but a U.S. study found walking prevents bone loss caused from prostate cancer treatment.

Lead author Paula Chiplis of The Johns Hopkins Hospital in Baltimore said men with prostate cancer frequently receive radiation therapy to kill the cancer cells followed by months of hormone therapy, which decreases testosterone and estrogen that feed cancer cells.

Men undergoing hormone therapy lose between 4 percent to 13 percent of their bone density annually, compared to healthy men who lose from 0.5 percent to 1 percent per year, beginning in middle age.

The study involved 70 sedentary men with prostate cancer randomly assigned to a nurse-directed, home-based walking program or usual care -- no exercise during radiation treatment, with more than half also receiving hormone therapy.

The study found prostate cancer patients undergoing hormone therapy that walked about five times a week for 30 minutes at a moderate pace maintained or gained bone density, while those who didn’t exercise lost more than 2 percent of their bone density in eight to nine weeks.

The findings were presented at the American Society for Therapeutic Radiology and Oncology’s 49th annual meeting in Los Angeles.