It depends on what type of ox you have. Assuming that it is btg or spa I would say 35-50 mgs for at least six weeks. I say this because I used btg at 27.5 mgs/day for six weeks and it worked well, I just feel now that about 40 mgs/ day was needed for the results I was hoping for. What type ox will you be using? That makes a huge difference( I don't know that I would use anything other thant the btg or spa ).