I save the clen for dieting. It helps to burn more calories and thus get lean faster. I could see it cutting into your calories, burning more and then your muscle will not have the same amount of nutritional support. I have tried to use it after PCT but honestly, I had never seen a difference. The way guys suggest it at this time is to keep the dose at 40mcg. Personally though, I don't think it is going to help much. Your GH and insulin on the other hand, not that will make a big difference. IGF can also be fun to run after PCT to help with a better pump and make training a little more fun, while maintaining better mass