my left pec is dominant so i inject winny in my right pec a lot. It might not do anything to siteinject. Who knows, i do it anyways,;only with winny though. I personally love the soreness that it gives in my chest the next day but a lot of people seem to think its stupid to inject in your chest. Just make sure you always aspirate and dont go too deep. I inject in the outer part of my pec where it seems thickest.