Originally Posted by
Dalton Clark
Rippetoe's dietary instruction comes directly from who he is most fervently addressing - vastly underweight individuals. He also addresses obese individuals in his books. You will notice that he does not provide any guidelines for individuals who are not either obese or substantially underweight. This is because Rip doesn't particularly enjoy discussions about diet and nutrition. The in-house go-to person for nutrition information is Dr. Feigenbaum. He finds nutrition to be very interesting.
There is a theoretical maximum to the amount of muscle protein synthesis that can occur in a particular trainee. By corollary, there is a theoretical maximum to the amount of calories that can be partitioned for muscle protein synthesis. This implies that calories taken in above the muscle protein synthesis plus maintenance threshold will be stored as fat. If your body can only utilize 500 calories per day to produce muscle mass, eating 2000 calories over that value will net you 2000 calories worth of fat assuming perfect retention. An individual that is substantially underweight will be able to use more calories for muscle protein synthesis. However, someone at a decent weight should not eat 2500 calories over maintenance. More calories does not mean more muscle mass.