I just sit in a 120 degree angle and have never had problems with my back, wrists, neck or anything. Just make sure the screen is high up that you don't have to bend your neck...
No, seriously. What sort of setup do you mean? I just lie back on my chair, so all you need is a chair with an adjustable back. I also lower it all the way down so the desk is at shoulder height. This forces you to rest your hands on your elbows instead of your wrists and to have them on a straight line.
Your desk just needs to be deep enough to allow your arms to be on it past the midway to the elbow, so you don't have to actively raise your hands. Lowering your chair also has the benefit of bringing the screen at eye-height, but you could just get a high desk...
This forces you to rest your hands on your elbows instead of your wrists and to have them on a straight line. ... deep enough to allow your arms to be on it past the midway to the elbow
Agreed. I don't put the chair back, but I have two of those rubberized "keyboard" wrist supports (the ones that are about 20x3 inches) across the edge of my desk (one for each arm), and I type with the point of my elbows just off the wrist pads, my forearms supported by the base of my forearm just near the elbow. I found that if I rest the point of my elbow on the wrist pad it's not as comfortable. Since they are side by side, they stretch the entire length of where I'm going to move my arms, for both using the keyboard and mouse. And since my arms are supported near the elbow, the natural most effective typing position for my wrists is straight, or what high school typing teachers would call "up", not resting on something. The pads put my forearms almost perfectly level when my hands are on the keyboards.
I don't use the gel or bead filled ones because they don't keep their shape as well, and I don't find their rounded edges to be as comfortable -- I know the exact position to be in based on being able to feel the edge of the pad with the base of my forearm. I need something to support the weight of my arm, not change its shape to the contour. Unfortunately the rubberized ones are getting hard to find.
In a pinch, I use rubberized mousepads, which every office seems to have lying around and no one uses. When using these, I just put one under each elbow and use the edge of the desk like I'd use the edge of the keyboard wrist rest, feeling out the edge with the base of my forearm. This isn't ideal though. I need to stock up on more of these "keyboard wrist rests".
My desk doesn't permit that and I like it higher anyhow, so I lean back in my chair and simply put the keyboard in my lap. Once you're used to it and relax, it meets all ergonomics criteria I've seen; flat, comfortable wrists, no stress or strain, etc. It's a Microsoft split keyboard, which helps, but my non-split laptop, which I use in the same position, is fine too.
(Also, I think switching to Dvorak may be helpful. My wrists move a lot less with this layout than they do with QWERTY. Touch typing is a good idea but where QWERTY discourages it, Dvorak makes it simply the best idea; you don't have to try, it just happens. YMMV; please note I said "I think", and I mean exactly that, not "It has been proved that".)
Anecdote: I typed ~95 WPM on Qwerty, hunt-and-peck* , and switched to Dvorak three or four years ago. Touch-typing Dvorak just feels natural to me, too. I haven't measured my speed in a while (over 60 WPM, who cares?), but Qwerty feels like a chaotic jumble by comparison. It's mostly a comfort/ergonomic issue for me.
It's a tricky thing to get hard data about, though, and the whole Qwerty vs. Dvorak thing somehow got caught in some religious argument about the free market, so there's probably too much noise to ever sort it out.
* Hey, I taught myself to type on a Commodore 64 as a kid.
I sit the same as the GP, if it helps. Large cheap IKEA chair, with my feet up the wall and leaning back as much as I can. Never ever had any position problems.
Unless you have specific support for that, as in a special chair/desk setup, that's horrible advice. I'd almost like to see what you're doing since I can't imagine it being comfortable. You got a picture maybe?
Unfortunately I don't, as the chair I have now is a stupid dorm chair. Any office chair with an adjustable back will do, just make it go back 120 degrees...
Didn't the BBC recently report about a study which concluded that obtuse sitting angles were actually better for your back than right angles? (As always, acute angles suck) If that's true, then his 120 degree sitting position might not be horrible after all.
That said, if he's in essentially a lying position all day, there could be other issues (like loss of muscle definition) at play.
