Over the years, I've noticed that if I'm stuck on a story and can't figure out how to even think my way toward a solution, one of the most helpful things I can do is to listen to other storytellers talk about their work. In particular, I'd put on one of those bonus material discs from a favorite movie and listen to directors and screenplay writers discuss their approaches. (My favorites are Peter Jackson, Fran Walsh, and Philippa Boyens talking about how they adapted The Lord of the Rings into film, how they decided what to leave out, what to expand or re-arrange, that sort of thing; because I know the books so well, I can follow their interpretive process.) I come away re-charged because the story-telling is similar enough and yet different enough from what I do in prose. I've also gotten much good perspective from books on screenplay writing for much the same reason. I don't want to write a script for a movie or a play, but I do benefit from that particular way of looking at story, character, dialog, and action.
I find, though, that this strategy is more useful for "getting-unstuck" than for "general writerly health." I am a fiction writer -- I deal in prose, not script, not poetry (although I greatly admire people who can do them!) I'm struck by how many writers I know who have some other areas of creativity in their lives. Music springs immediately to mind, how many writers I know who also sing or play an instrument, many of them at quite a high level of proficiency. I suspect the same is true for painting, for knitting, for cooking . . .
I've been studying piano for about 12 years now. It's my first formal music training, although I sat through about a gazillion lessons with each of my two children (the rule was, you begin at 5 and keep studying as long as you live at home). Finally it was my turn. There's a special joy in being an adult student, already appreciating the importance of repetition, analysis, lyricism; being able to choose music I love, whether it's in the standard repertoire or not; being very clear that this is for my own pleasure. I'm currently in the midst of a love affair with the French Impressionists.
I don't know why I should have been surprised when music lessons started having an amazing effect on my writing. I conceptualized this that playing the piano and reading staff notation was forcing my brain to work in a different way, but I think it's more than that. As I learn a piece, I go on a journey inside the structure of the music. Music isn't just isolated notes, any more than writing is isolated letters. It's movement and interaction, harmony and dissonance, rising and falling tension. This is especially true for "narrative" music. (I have no idea if that's a technical term, but it's one that makes sense to me.) I get to immerse myself in a very different form of "story-ness," one completely without words, one that exists only in the moment and in my memory. Writing's like that -- the ideas and images are flashes of electricity and squirts of neurochemicals in my brain, evanescent -- and then I capture them. Well, I make an approximation of turning them into a form that endures over a somewhat longer time.
None of this translates directly into better writing. What it does is push my mind in different directions. It's like creativity yoga. The bonus is that besides "improved overall conditioning," I come away with new experiences as well, so expect music to play a greater role in my work as time goes on!