During this brief period I developed blood clots in one leg from sitting too long, and was really lucky to survive two large pulmonary embolisms. I often share this story as a warning to others. BTW, I average wilderness hiking for about ten hours a week (gentler walks when recovering from surgery) and that was not enough to prevent the blood clots.
Now, I use a 20 minute timer to get me up and walking around for a few minutes, 3 times an hour. Frequently standing and walking around is a recommended habit! Bad sitting habits almost killed me, and I needed over two years to mostly recover, so please take this seriously.
I wish I have your discipline to take frequent breaks though.
If you have assorted health issues you may also not be inclined to move around much. The "not moving much" may be the result of other health issues, not the cause of them.
Bonus: It's also been built with men's genitals in mind (http://www.youtube.com/watch?v=_HIt3D7Ivfc).
On a non-chair related note, to those of you who take breaks, I strongly recommend that you consider taking exercise breaks rather than simply walking around or stretching. Google "grease the groove". I'm currently GTGing pull-ups and overhead kettlebell presses.
These originate from Rautalampi, Finland. Just over 40 miles from where I live.
I'd also recommend trying before buying.
What chair do you use at home?
I'll switch between reclining with it(I have a multi-level home desk setup and can stretch my legs out), sitting at the edge of the seat with the legs on the ground, sitting using the footrest, or standing.
Maybe I have to try that now. It's a pity that treadmills are so pricey.
Incidentally, the ability to move around in different positions while reading is a major reason I bought the iPad.
I find my spine tends to be in a C shape more while using the iPad, unless I am lying down.
I am going to experiment with a twist board and an elliptical trainer with standing desks. Starting today, with the desks.
The same company also makes a compact elliptical.
The chair cost be around $700 at the time, so that's <$100 per year or <$0.50 per day.
Also the chair came with a 12 year warranty. A couple months ago the pneumatic cylinder went out. I called a local Aeron deal and since I bought the chair from a authorized dealer, they sent somebody to my house and fixed it for free.
(This is not to say, by the way, that you might not experience chair-related pain in your thirties, or even earlier. But the odds do seem to go up in middle age.)
My only concern -- highlighted in the article -- is that my Aeron isn't enough. I'm amused to find that experts think the thing is too low -- it is too low. But maybe that was partly because my pneumatic cylinder was about to go out -- mine just went. Fortunately my chair is also under warranty!
I'll look into these wacky standing chairs.
 Slightly off topic, but: I wish, when I was in my twenties, poorly paid, and absent-minded, I'd gotten email every six months saying "the dental checkup you're about to skip will eventually cost you something like $10k or $15k in root canals and crowns. Or, alternatively, you could lose your teeth and spend forty years cursing your bridgework and dentures."
And to the parent: If you like your Aeron, you should seriously consider the Embody - lots of time and money went into making it a significant upgrade worthy (imho) of the premium price.
The seat pan on my Dad's chair (which he bought around 1997) broke a couple of times, at which point they simply replaced the entire chair.
He's been using it without complaint ever since.
The short answer: no. Chairs appear to be one of these products in which you get what you pay for.
I highly recommend them, if you can get one for your home office (or if you work in a office that allows desk of your preference). Some people go even further and get a treadmill underneath the desk, but I like to switch between sitting & standing personally. Standing up while working gives me an active feel to it, and I find myself avoiding procrastination since my legs would get tired if I were to spend hours surfing the Web (sure, I could adjust the height so that I can comfortably sit again, but the decision becomes more 'conscious' in a sense).
Most people have weak core muscles due to chairs with backs, so if you're going to try out this kind of chair, don't be surprised if you can't do it for more than an hour a day at first. Also, it may not be a good idea if you're tall, since the ball can only inflate so much. If the angle between your upper legs and your body isn't greater than 90 degrees it probably won't work for you.
I still have a normal chair. If you're working crazy hours, you need to give your supporting muscles a break sometimes.
Oh, and it's really cheap: mine was about $60 if I convert from my local currency.
EDIT: here's an example, but don't buy it online if you haven't tried it:
That's my problem with all these chair discussions. I don't have a problem buying a chair that works great, or a chair that doesn't "look like a chair" (as the article mentions), but I do have a problem dropping $800 on a chair sight unseen.
I'd have that problem no matter what, but being 6 foot 4 inches (aka "99th percentile height", or at least I've seen one source place that as the 99th percentile cutoff) really doesn't help. The probability of spending $800 on a chair that simply doesn't go high enough is too large. But I have no idea how to try a wide variety of chairs out for any reasonable period of time.
A ball chair is not an exercise ball chair. Looking at the illustration on Wikipedia, it's clear that a ball chair forces a C-shaped spine. Your spine will stay in an S-shape if you sit upright on the "chair" I'm referring to.
I'm just going to continue as usual, using the ball chair and alternating with a normal chair if needed. My spine feels great and definitely has a more natural shape when sitting on the ball vs. a normal chair.
This can be setup with the desk surface at standing height. The smaller shelves become under-desk storage or monitor stands.
There is also a wider model of the same desk that currently goes for $159.
Rant (stop reading if you're not interested): Posting it here, since we're all so obsessed with printer friendly versions of articles, because we can't stand clicking to view the second half of an article. Unfortunately, the printer friendly version doesn't contain links like this one.
One's head and neck are pushed slightly more forward than normal and don't have their normal degrees of freedom; this causes some stiffness over time.
One can sometimes "flip up" one's elbows to rest on the armrests, as when reading, or resting. Over time, this tends to "bang" them against the armrests, which can really hurt the ulnar nerve, which is unprotected on the "backside" (upper portion) of the elbow.
If the chair has a fixed angle at the knees, you'll need to get up from time to time and walk around--or at least, I did. The fixed angle prevents the lower back from moving around much and doesn't allow one to "stretch" out.
It's tough to keyboard comfortably in a reclining chair. One ends up disproportionally compensating for poor ergonomics with one's chest muscles. In addition, your shoulders tend to roll forward. Either of these can cause thoracic outlet syndrome over time, which is like carpal tunnel syndrome, only it affects your entire arm.
It is for these reasons that I switched to a standing desk, where my body can move the way it was designed to. Keyboarding is still an issue, but if you buy a split keyboard Datahand you can mount each half near your hips and keep your shoulders back.
Maybe I just need to bring the patio furniture into the office.
An anti-fatigue mat is an excellent investment, but even with that be prepared for a few weeks of achy feet/legs. You get used to it eventually, but man, it feels nice to crash on the couch in the evening.
I'm not sure if "ball chairs" are the same as you mean, but I guess they're.
A side effect of sitting with good S-shaped posture on a medicine ball is that I don't really "sit" any more. Instead, I straddle the ball as if I were riding a horse.
However, for me the reason I switched to sitting on a medicine ball has nothing to do with back posture and everything to do with preventing a recurring pilonidal abscess.
Cycling puts an unnatural curve in our lower back, very similar to sitting in a chair, and due to the way the muscles work, cyclist end up with tight hip flexors and hamstrings and stretched spinal erectors (sorry, I've been out of Physiology for a while so can't remember the exact names of the muscles) which can further exacerbate the problem. Compare a cyclist with a runner, and you can see a noticeable difference in posture.
However, I wouldn't call it a 'negative health impact', as the activity is improving your health. Just be sure to stretch, and counter the muscle imbalances that the sport produces.
Many sports have similar results because they are unnatural. For example, snowboarders in big mountain areas end up with a unnaturally strong/tight oblique muscle on one side and one stronger leg. Surfers likely don't have this issue because the majority of their exertion occurs during the paddling phase and the length of time actually spent riding the wave is quite short.
Drury and Francher studied the original Balans kneeling chair in 1985, concluding that overall it was "no better than conventional chairs and could be worse than well-designed conventional office chairs." Lander et al. conducted another experiment in 1987 comparing the kneeling chair with a conventional chair and concluded that their experimental data "do not support the manufacturer's claim that the Balans chair is likely to decrease complaints of [lower-back pain]". A 1989 study on a sample of 20 subjects concluded that the Balans chair promoted greater lumbar curvature than the "straight back chair" during relaxed sitting, typing and writing and that it could contribute to treatment of lower back injuries. A more recent study from 2008 confirms that "ergonomically designed kneeling chairs set at +20 degrees inclination do maintain standing lumbar curvature to a greater extent than sitting on a standard computer chair" and suggests that "Further research with a greater number of subjects and on different chair designs is warranted.""
Links to references on the Wikipedia page: http://en.wikipedia.org/wiki/Kneeling_chair
(Sorry for my English).
But you can ALSO help by investing in a chair specifically designed to prevent the pressure on your leg veins. The only one I know of is the HAG Capisco, and we have had them for two years now.
They are worth every penny.
The only downside is that, because your weight is all on your feet and ass -- not your thighs -- if you sit with poor posture, your ass will fall asleep.
But this is really a feature, since it reminds you you're not sitting right and should stand up.