I found this article on your maximum potential really interesting. The author has a very interesting concept where he has created formulas to calculate how muscular you can get. This is done by using your wrist, ankle, and height measurements combined with a formula for each body part that was derived by taking measurements from 60 years of natural body builder measurements. The idea is this is the ideal you can shoot for which so far no one has surpassed naturally. It’s a really interesting way to think about it and I think provides a much more realistic expectation of where you can get. If you can have an 18″ bicep and you’re at 16″ you are only two inches off of being Olympic level (assuming you are at 10% body fat and have followed the formulas correctly). Creating formulas based on what you could attain if you were to meet the best is a cool way of looking at it. Especially in an area that is so rife with misleading expectations (he gains 8 pounds of lean mass in one workout, hint: he drinks about 8 pounds of water). If you want more information on this you can check out Transformible.com which dives deeper into this information.