If you’re a professional (or even proficient amateur) musician, you practise your scales, and other exercises daily. This keeps your muscle-memory alive for the basics of how they will move when playing pieces of real music.
What’s the equivalent for engineers?
Maybe mouse and keyboard exercises to keep our hands as productive as possible? Or mental exercises to ensure that the critical facts we need to know are to the fore. I can’t imagine not being able have instant recall of my multiplication tables for example.
And of course this changes over time as more and more mundane stuff is done for me by my computer. A couple of decades ago, a logic designer would have been using Karnaugh maps on a daily basis. I remember “using” them at university in coursework, and I got better, the more I did them./ But I haven’t used them in the real world, despite doing logic design for well over a decade!
Update:
And I’ve found someone with (at least) one answer