Most say no....if you cement the gains once they are made they are permanent, from what I understand. I just keep going till I am at the size I want then worry about it later. If you are a little older because of decreased efficiency of the bodies endocrine system gains may be slower, but you can still gain and maintain those gains.
im just wondering because i havent bought this yet. I would hate to pay 50 bucks only to find out that if i want these gains i need to do it for the rest of life or else i will regress back to what i was before.