Unfortunately there is a lot of variation in how the HRT might affect your body. As well, it depends on which drugs and how your body reacts to those you take. Since you are so young, it is likely that the effects will be more dramatic than in older transitioners. I would think this will mean that you will not likely develop large or "ripped" muscles. As mentioned above, you will also get a sub-cutaneous layer of fat that will cause your muscles to appear less defined. YMMV....