Bill, I have been using Myostat since May. I have definitely made gains in that time, mostly in the last two months (I suspect that Myostat may have a cumulative effect.) I changed to an HST program 10 weeks ago so it is difficult to assess how that may have impacted my gains versus the Myostat. However, after over 30 years of active training, including 18 years continuous from age 39, I have put on 8 pounds of LBM since starting on Myostat. That is pretty good for someone with my training, not to mention chronological, age. Coincidence? I doubt it but I was not training in a controlled environment so I can’t say definitively that it is all due to the Myostat. However, I am convinced enough that I intend to continue to use it. I probably need another year on it to make a supportable definitive statement.