If you read the tech blogs, lately you've been seeing a lot about stand up desks. It seems the office dwellers are finally catching on. It's something we audio nerds have known forever. Working standing up is a great idea. I hardly ever take a seat when I'm mixing, even on long gigs. Standing keeps you more alert and keeps your metabolism from slumping.
There are a few things you should do as far as ergonomics go. Making sure you set up your mix at a good height, so you're not slouching to reach the faders is the key thing. You want to be able to stand up nice and straight and have the console within easy reach. It's good if you have a mat to stand on too. The ones you see in machine shops and commercial kitchens are great. Those are the ones with the big round perforations and they're like walking on a cloud. Failing that, you should have something handy to put one foot up on. It can be as low as a chunk of 2x4 or as big as a tool box. The point is to alternate putting one foot up. It keeps your spine happier and gives your knees a break.
In the office things can be a little trickier. There are companies out there making automated desks that jump up to the height you want when you want to work standing. That's a bit much. For my desk at work I just got a nice looking portable file box. Most of the day I leave it on the desk with my laptop on it. When I come in to look something up or so a quick email check, if I don't sit down I'm less likely to get stuck in front of the screen and go back to what I was doing. It's a little more difficult if you've got a desktop computer but if you search around there are plenty of low cost or even DIY solutions to move your monitor, keyboard and mouse as needed.
For the studio cats, this isn't such an easy trick. Spending twelve or more hours at the helm can really do a number on your back and other joints, as well as slow down your metabolism. That makes it harder to maintain a good level of concentration and can even make it harder to keep extra weight off. Everything I've read recommends taking a five minute break about every hour. You don't have to do much, take a spin up and down the hall, run to your car, or just stay in the control room and do some stretches. Breaks are suggested even more frequently for your eyes. Taking a minute or two every half hour and staring at something far away can do wonders for preventing eye strain.
Ergonomics aren't something that people in our business think about very often. But when you look around at the old timers, you can see just what kind of aches and pains you'll be in for if you don't watch it when you're younger. I can speak from experience. You don't give your back a moment of thought until something bad happens, then it's all you ever think about. Save yourself some grief and think about it a little before you have a bulging disc or a pinched nerve.