yomama said:You can say "genetic limit", but can you explain what inside the body makes you stop from going beyond?
The muscles in your body are in a state of constant flux.
Protein is flowing in and out at pretty quick rates. Most of the time protein in = protein out, and youi maintain muscle size.
Working out raises both protein in AND protein out, but protein in just a little bit more. Over time, gains can accrue.
Steroids will both INCREASE the protein in by triggering cellular growth and decrease the protein out by inhibiting cortisol. This will actually happen on its own without working out, but couple it with working out and there's a synergistic growth effect.
However as you get bigger and bigger, the amount of protein leaving the muscles increases (because there's more of them interacting with the blood), but usually the same amount of protein going in. THis is why you have to increase the steroid doses as you get bigger; you need a stronger "protein in" signal to counter the ever increasing "protein out" that results from growing very large.
Genetic limit just refers to a point at which a natural trainee, no matter how he trains or eats, cannot overcome the tendency for the body to breakdown the muscle tissue. ie protein out cannot be overcome with a training stimulus