No matter how mundane some action might appear, keep at it long enough and it becomes a contemplative, even meditative act.
In private correspondence the great mystery writer Raymond Chandler once confessed that even if he didn't write anything, he made sure he sat down at his desk every single day and concentrated. I understand the purpose behind his doing this. This is the way Chandler gave himself the physical stamina a professional writer needs, quietly strengthening his willpower. This sort of daily training was indispensable to him. Writing novels, to me, is basically a kind of manual labor.
To deal with something unhealthy, a person needs to be as healthy as possible. That's my motto. In other words, an unhealthy soul requires a healthy body. This might sound paradoxical, but it's something I've felt very keenly ever since I became a professional writer. The healthy and the unhealthy are not necessarily at opposite ends of the spectrum. They don't stand in opposition to each other, but rather complement each other, and in some cases even band together.
As I suspect is true of many who write for a living, as I write I think about all sorts of things. I don't necessarily write down what I'm thinking; it's just that as I write I think about things. As I write, I arrange my thoughts. And rewriting and revising takes my thinking down even deeper paths. No matter how much I write, though, I never reach a conclusion. And no matter how much I rewrite, I never reach the destination. Even after decades of writing, the same still holds true. All I do is present a few hypotheses or paraphrase the issue. Or find an analogy between the structure of the problem and something else.