In addition to good exercise and better diet, I suggest you get off of caffene. The diet should be very little land animal meat, no poultry fat, no dairy, and lots of fresh vegetables and fruits. A great book is "Beating Prostate Cancer With Diet and Hormome Therapy" by Dr. Snuffy Meyers, a prostate cancer oncologist and long term PCa survivor.
I also suggest you ask your doctor about Jalyn. It combines Avodart and Flomax. The Avodart stops the more powerful DHT and should be a part of hormone therapy. The Flomax helps with the urinary issues that can cause problems during and after the radiation.
I found the increased exercise and elimination of caffene has really diminished the hot flashes and is helping me control my weight. I go to the club five times a week and have a balanced program between fat burning cardio and weight for strength and bone strength. Read "Body For Life" by Bill Phillips for good exercise programs and diet basics.
Rather than caffenated drinks I now drink three to five cups of green tea each day and lots of water. I also cut back on sugar based fruit juices like orange juice and drink much more tomato juice. Lower sugar, more vit C, and Lycopene than orange juice. Also a glass or two of red wine nightly with dinner.