I recently read a write up on Myostatin blockers in MD. A lot of research is being done on myostatin blockers in rats and cows with some success. Increases in both muscle fiber size and number were noted. In the cattle large amounts of muscle mass increases was seen but along with greater muscle damage risk, reduced aerobic capacity, and heart and lung problems. A lot of research still has to be done on it before any human will have the chance to take it imo.