> Doping with anabolic steroids also seem to act partly by recruiting new nuclei.[7][8] It was recently shown in mice[9] that a brief exposure to anabolic steroids recruited new muscle nuclei. When the steroids were withdrawn, the muscle rapidly shrank to normal size, but the extra nuclei remained. After a waiting period of 3 months (about 15% of the mouse lifespan), overload exercise led to a muscle growth of 36% within 6 days in the steroid-exposed group, while control muscles that had never been exposed to steroids grew only insignificantly.

aqueueaqueue probably meant this part ^. If you do steroid once, then you stop doing steroid, its effects remain, according to wiki (in mice).