Is there a name for the idea that learning one skill can help you improve in other skills (not necessarily directly related)?

It’s been a while since i was in uni doing theory but I think there’s a term called “domain transfer”…
I’m not sure of support in terms of studies + theory but practically as a teacher I do it all the time in a couple of ways:

1. Use the vocab of the other domain so that they can relate to it or memorise it better
e.g. For my creative writing class: “You know how in tai chi there is the yin-yang symbol? It’s a philosophy that in the dark there is light and in the light there is dark.. so when you create characters for your novel you don’t want to create characters that are all evil or all good. It’s really boring if things are black and white, because really, people are rarely like that. So you want to add something admirable in your villain,” (point to the white dot in the black) “and something you thing is bad, a tragic flaw, for your hero” (point to the black dot in the white)

2. Teach students to think on a meta level
e.g.,
—> Teaching critical thinking, which students can then apply to a number of domains, whether it is essay writing (look at this essay and come up with 3 questions you want to ask the writer)...
—> Flag them to look for parallels (and differences)
“Ok, we made a list of things that make a good essay – let’s see, organisation, punctuation, spelling…. now what do you think would be the equivalents for public speaking?”

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@lapilfou: What compelled you to ask this question?

Not sure this would be what you’re looking for, but you might be interested in looking at Brain Fitness and the broader Neuopsychology

Are you thinking of something like cross-training?

Or are you thinking of ideas like “kids who grew up playing nintendo will be better surgeons”.
http://www.wired.com/medtech/health/news/2004/12/66086
http://gizmodo.com/346034/surgeons-get-better-playing-nintendo-wii

this is called positive transfer.
It’s basically where you might say, be a basketball player, and you use your skills in that to learn how to play netball.
Sadly I can’t think of any better examples.
Maybe a good backup would be if you could find a sports star who changed sports during their career. This shows they were able to do this because of the skills they learned in their first sport.

You could also be thinking of Transference of Learning , which in a learning and development context is sometimes only referred to as transference, but not to be confused with the same term used in a psychoanalysis context

Its called the “training effect” at least in a program I’m involved with called Cogmed. Its where you stimulate particular sites of the brain and several months later, there’s a trickle down effect. Areas of the brain that were not stimulated become activated and you’re able to perform tasks totally unrelated to the training you had.