The occasional ramblings of a freelance lexicographer

Friday, February 29, 2008

Laid-back sitting

A few people have asked about the 135 degree sitting angle mentioned in my RSI Day message (see below). It does sound odd and I think 135 degrees is quite ambitious, but I've just taken a photo of myself at my desk and I reckon I get an angle of about 115 degrees between my spine and my thighs (measured very accurately using a protractor held up to the screen!).

Give it a go!

International RSI Awareness Day

As I've mentioned before, I'm a long-term RSI sufferer and I used to be quite evangelical about spreading the message of healthy computer use. I have to admit that I got a bit bored of talking about RSI (Repetitive Strain Injury) and haven't been pestering people about it so much lately. But today - 29th February - is International RSI Awareness Day (as the only day that isn't repeated every year) and there have been a few worrying trends lately that have renewed my campaigning fervour!

In the eight years since I first developed RSI, people generally do seem to have become more aware of the condition and the possible dangers of regular (or constant!) computer use. Lots of people though are a bit vague about what they should be doing to avoid suffering problems and more still are rather lax about sticking to the rules they do know about. So I thought this was a good opportunity to recap a few basics and point up a few 'new' areas of worry:

Basically, there are two keys to healthy computer use - good posture and frequent breaks:

So let's start with a mini body-break while you're reading this - let go of your mouse, sit back in your chair, let your hands sit in your lap and relax your shoulders ...

Many of us know the basics of a good workstation set-up:

1. Your monitor should be a comfortable distance away (just over arm's length) and the top of the screen should be roughly at eye level (so you look very slightly down at most of the screen - thus stretching out your neck rather than scrunching it).

2. Your chair should be high enough so that your hands drop slightly down from the elbow onto your keyboard. The worst typing position is with your elbows down, your wrists resting on the desk and your hands arched up. If possible, try to type with your hands hanging down loosely.

3. Don't keep your hand clamped on your mouse!! Make sure your mouse is easy to reach so you can use it without moving your elbow away from your body - get a longer lead if need be (or a wireless mouse solves the problem completely). And try to only put your hand on your mouse when you're actually using it.

What happens though if you're using a laptop? All good ergonomic intentions seem to go out the window!! I've noticed in recent years, as laptops have got cheaper, people are using them more and more, either for work or just extended periods of e-pottering. By design, they are the most unergonomic bits of kit imaginable, with screen, keyboard and mousepad all scrunched up together and the temptation not to even sit at a proper table. And I'm not the only one who's noticed - there was a recent campaign aimed at students called "Laptop Losers" highlighting the dangers of regular laptop usage. So if you're going to use one for any amount of time (i.e. more than about 15 minutes at a stretch), you really should think about taking a few measures to improve the situation. The first thing to do is separate out the key parts (keyboard, mouse and screen) so that you can position them more comfortably (in line with the steps above). This is incredibly easy - a separate keyboard and mouse will plug into any laptop and cost so little there's really no argument. Then you can use the laptop screen and move it further away from you and to the right height. A couple of chunky books will do the job, or you can get laptop stands, like the funky 'Jellyfish laptop stand' below (just Google the name for suppliers), to prop it up.
Once you've got your kit set up comfortably, the next thing is to think about how you're sitting. When people think about good posture, they think of sitting up straight, which isn't wrong, but isn't always that straightforward. Some people feel they're straight when they're actually quite slouched forward, others, like me, tend to sit forward on their chair and arch their backs. So the only way to really get your posture right is to set your chair up correctly and then try to sit in it properly. By this I mean with your feet flat on the floor (or a footrest if necessary) and your back leaning against the back of the chair. Some research that was in the news at the end of last year suggested that rather than sitting with your body and legs at 90 degrees, you should actually be aiming for 135 degrees. Looking at the media reports, this leaning back position looks rather odd and would certainly make using a computer quite awkward. It's not so silly though when you get a greater than 90 degree angle by keeping your body more-or-less upright and angling the seat of your chair down slightly towards the front, so your thighs drop down very slightly from your hips. It's the same principle that those funny 'kneeling chairs' work on and once you get used to it (and get the right angle for you), it is quite comfortable. If your chair doesn't adjust, a wedge-shaped cushion will have the same effect.

And on that relaxed and comfortable note, I'll leave you to get back to work. But remember, don't get let yourself get too attached to your computer - breaks can involve coffee (and even cakes!), but they can also be just a couple of minutes relaxing back in your chair while you're reading something.

Computers may dominate our lives nowadays, but you shouldn't let them damage your health!