> When a movement is repeated over time, a long-term muscle memory is created for that task, eventually allowing it to be performed without conscious effort.
But this article is about enhanced muscle recovery and volume, not about motor learning. I wonder if that's an abuse of the term "muscle memory" or just a different sense. I'm not finding that sense used in a quick search. But the term is also used in the review paper that this article is about, so apparently it has a specialized sense in that discipline.
According to Wikipedia muscle memory as retained skills isn't about muscle fibers, but neurons.