Xofigo (Radium 223) is one treatment targeted at bone mets..
http://www.cancercenter.com/cancer-drugs/Radium-223/
Provenge is another systemic therapy for advanced PC that works well for most who have tried it..
To help you more, we need more information..Your age, PSA when diagnosed, PSA now, Gleason score, ...
The treatment you are undergoing now can reduce your cancer to undetectable levels or at least very low levels which should allow you to continue enjoying your workouts with no restrictions, at least for a while..After that, there are more advanced drugs and treatments that can hold your cancer at bay for a long time....Only when the bone mets no longer respond to treatment must you curtail your activities..Are you taking a calcium supplement? This will diminish the bone loss caused by the HT....