Okay, have you heard about all the research that shows that sitting down for hours at a time is bad for you? If you haven't, then let me summarize:
1) Sitting lowers the activity of various lipase enzymes involved in breaking down fat.
2) Lowering lipase enzymes has profound metabolic consequences including lowering levels of "good" HDL cholesterol, upping the bad kinds, knocking liver and pancreatic enzymes out of whack, and a bunch of other things you don't want to hear about.
3) It isn't simply that sitting implies a sedentary lifestyle. Sitting for hours makes changes than even an hour of vigorous daily exercise can't counter.
4) It isn't just about the exercise; simply standing instead of sitting makes a huge difference.
Hmm. A bit of a problem for us writerly types, isn't it?
But, then, Hemingway wrote standing up (supposedly because of a back problem). Thomas Wolfe also wrote standing up, though he never said why; Wolfe was six-foot-six, so he often found it convenient to compose using the top of a refrigerator as a desk.
Looking into it, I find that Virginia Woolf and Winston Churchill also wrote standing, and that Philip Roth continues to do so today. In fact, in the nineteenth century, "standing desks" were quite common, and Charles Dickens and Lewis Carroll both composed while standing. (I'm sure Faye Booth could have told me all that, and probably even has vintage postcards showing what a standing desk looks like. No good Victorian home should be without one.)
Somehow standing and writing seems more compatible with scratching along with a pen or pencil than with tapping at a keyboard, but I'm assured by what I read here and there that standing and whacking at a keyboard is easy once you get used to it. Those folks who check you in at the airlines do it all day long.
Certainly I'm capable of thinking about writing while on my feet. After all, I get my best thinking about stories done while I'm out walking, and a good walk is usually my first remedy when I get stuck. There have been quite a few times where I vaguely wished I had a voice recorder with me, as sometimes the words start coming while I'm out walking, and I have to rush home like someone with a bladder problem. (Alas, when confronted with an actual voice recorder, the words in my head vanish. There's something about my writing process that requires seeing the words going down on the page--even if that page is in fact a computer screen.)
So I plan to try writing while standing and see how that works. For the moment, the arrangements will consist of a box stacked on top of my existing desktop. I'm also advised that it's useful to have something to prop up first one foot and then the other, sort of like a bar rail. I gather the Victorians had some sort of stools to lean back against as well, though I'm not quite sure how those looked or worked.
There are a surprising number of people out there now who are working all day while standing on treadmills moving at about a mile per hour. (By 'a surprising number' I don't mean many thousands. The fact that there's more than, say, three people doing this came as a surprise to me.) I am assured by enthusiasts of this technology that you adapt rapidly, and your mind is more active, alert, and less distractable. I have a hard time imagining myself typing while walking, especially while writing fiction; as it is, I already have a tendency to forget to breathe. Stumping along on a treadmill while trying to work strikes me as fraught with comedy potential.
Nonetheless, there are whole companies out there now devoted to treadmill desks--here's a video of one of the inventors. Even he admits that writing is better done sitting down, but not everyone agrees; one YA writer now works while on a treadmill desk.
I'm not ready to head down that road yet. Nor am I ready to buy the $3,800 "English Bamboo and Lacquer Standing Desk c1880" offered by One of a Kind Antiques of Essex, Connecticut--not only because I don't have $3,800 to spend on such an experiment, but also because the concept of "English Bamboo" makes my head hurt. No, for the moment I'll just use that plastic carton atop my desk and see how that goes.
And if that doesn't seem to work, maybe I'll subscribe to the approach favored by Marcel Proust, Mark Twain, and Woody Allen. They all wrote in bed.