Myostatin is a protein that regulates how much muscle mass is produced. If the gene that encodes myostatin is hindered, mutated or blocked, studies show more muscle mass is developed.
Studies done on mice show that when their gene was "knocked out" they developed two to three times more muscle than mice that had the gene still intact. One researcher said they "look like Schwarzenegger mice."
In recent studies conducted, new protein interactions inhibiting myostatin that lead to double muscling, and the induction of hypermuscularity with myostatin antibodies, have been reported.
These studies suggest that proteins and drugs that interfere with myostatin may be helpful to many.