Wow, 400mg of test a week is the highest HRT dose I have heard of. I've never seen above 300-350mg tops. Put it this way, for many guys, 400mg IS a cycle! So make sure you keep your eye on your lab work long term, running a dose like this. 

As for doing a cycle, honestly, your test dose is plenty high, so my suggestion would be to look into another compound to add to it. Some of the more mild drugs that work well are EQ or Masteron. EQ will help with some added mass while not getting you overly bloasted. 16 wks at 400mg should produce some nice results, along with your test cyp at 400mg. Of 12 wks of Geneza Mast200 would be great, at 400mg EW. The mast would help with hardness, improve muscle quality and make your test more effective too. Personally I think you could do well with either. My personal suggestion would be to go with the Mast. It also has some intense effects on libido. I work with a lot of guys your age and they all love the masteron haha

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