Interesting study, though it's not 100 p clear. One group of mice were given no steroids; the other group of mice were given steroids. The one that got steroids grew significantly in muscle mass and nuclei in the muscles. The nuclei increase is usually concomitant with muscle growth. However, on discontinuing the doses, the got smaller like the other group. However, nuclei increase was rather well maintained. Thus, when both groups were reintroduced to muscle building stimulus, group with prior use regained rapidly, whereas other group did not...
Did they even train the other group to build muscle? If one group is getting doses and other group isn't and they are training equal length time, then dose group would gain more muscle in first place. Ergo, they have musch higher benchmark to regain some muscle. Unless they let the undose group train time-proportionately to how much muscle dosed rats had. Of course more muscle will be regained more easily vs building a little bit and laying off...
EG: natural bodybuilder can gain 30 lbs muscle over skinny self.
Natty bodybuilder trains 1 year and gains 10 lbs of muscle. Hormone fella trains same time but he gains 25 lbs muscle. If both these guys go on long vacation n come back, my theory is hormone fella would regain much more faster because it's muscle in the realm of what body can support naturally already...
This is sketchy idea... even I think.. but I'm willing to consider chemicals give you faster gains that are sustainable but only those gains to ur genetic limit.
But there's also theory that you can't have free meal. If it takes natty guys 3 years to max, something happened in process of time for his body to accept it. But force natty max celing on in 6 months, and body has not legitimately accustomed it's natural state to the processes built over changes in cellular levels. Homeostasis means it's not easy to keep your body in non-survival adaptations with trickery.