I think it is real. There are times where I don't feel im at my biggest, whether it be taking a week or two off from the gym or missing a few meals. I think most guys who are dedicated to the gym and eating every 3 hours feel this way when something is out of whack. It is funny but also sad, If say one night after i drank a lot and ate nothing i will usually wear a sweatshirt or something bulky out the following day because i feel my body has lost size.