New member here. Something I've been wondering, does heavy AAS use create a sort of "foundation" that doesn't really go away? Don't talk about tom prince or others who've stopped training entirely because of health problems. Reason I'm asking is that I know an older guy who competed in the 80s, he recently started a cycle again after like a 20+ year layoff and has exploded really fast. Makes me wonder if it's beneficial to juice heavily for a couple of years while young (while your body can still handle it) and then drop to HRT doses and blast for a month or two each year after that.
Yes, even a single course of steroids will have a permanent effect.
Steroids have been shown to rapidly increase the recruitment of satellite cells into muscle tissue. Once these cells have been converted to muscles cells they will not revert back. The rate at which the body without steroids can recruit these cells is much slower.
As we know when you come off, you loose much of the size, however there are residual gains that are kept. Assuming you have not shut down your own test levels through many cycles, you should be able to train and maintain some of these gains.
Most people ruin their test levels, so whilst their recruit additional satellite cells into the muscle, they loose muscle mass due to having test levels lower than when they started steroids.