Well I have a freind who weighs 280 and competes as a super Heavyweight at the Amateur levels, one step away from the pros, he's cycled for the past 10 years.
I also have a friend who weighs 190lbs and is planning a first cycle and wants to get as big as possible.
My friend on the football team weighs 230 lbs and is looking to improve performance.
There is no size fits all dose.