Choosing an ergonomic chair

by Thane Brooker,
1st December 2005

This week I’m on a mission to find the perfect throne (and I don’t mean the kind you flush). I spend over 10 hours a day at a PC and I suffer from lower back problems so I’ve decided, if it does the trick, it’s worthwhile purchasing a top-end money-no-object chair. Here are the results of my findings.

Requirements

I have three requirements:

1. Health. The chair should cure my back problems.
2. Function. The chair should allow me to concentrate on my programming. It must be comfortable and ‘unnoticeable’.
3. Bling. If I’m spending a significant amount on a chair, I expect it to look as good as it performs.

The chairs

Herman Miller Aeron

I am sure this chair needs no introduction. An icon of the dot-com era, this chair is considered a benchmark in ergonomic seating. it’s most striking unique feature is the semi-transparent mesh which forms the seat and back rest. I believe David Dimbleby sits on an Aeron on Question Time and my knowledgeable friend says “this is the best chair in the world” so it has to go on my list.

Humanscale Freedom

This chair was designed by Niels Diffrient, who wrote a book on ergonomic design, so it should be good. This chair makes it to my short-list because

1. It looks good and
2. It has so much hype that I couldn’t possibly NOT try it.

Steelcase Leap

This chair is regarded as a work of engineering as much as a work of ergonomics. In a review by Wired magazine, the reviewer refers to this chair as obsessive. Well I need my back for the next 70 years or so, so I really don’t mind my chair being obsessive. Lets give it a try.

RH Form Logic 400

The Logic 400 is RH Form’s latest top-of-the-range model, a Swedish company specialising in ergonomic seating. 50% of their sales are to Sweden, and there are no reviews or hype about these chairs on the Internet, so it will be interesting to see how this chair stands up (or should that be sits down?) against the badge kings above.

The Test

I believe you can’t test a chair just by sitting in it. Instead you need to use the chair in your everyday environment. I have two main uses for an office chair:

• Intensive computer programming (10 hour sessions).
• Interviewing and light-desk work (reading, etc.).

First impressions

This is all about the very first sit. It takes into account the first appearance and the first 10 seconds of sitting.

Herman Miller Aeron

I will probably never forget my first sit in an Aeron. I physically felt my body relax into the chair—my shoulder, back and stomach muscles all relaxed. The chair felt solid with all the bits in the right place—It felt GOOD.

Humanscale Freedom

This one felt like it didn’t fit me. I felt too tall for the chair—the headrest seemed to clash with my shoulder blades. Apart from that, it felt quite sporty. The seat and back rest weren’t padded and felt hard, but in a nice way. If I was blindfolded and you told me this was made by Recaro, I would have believed it. Overall though, the chair felt WRONG.

Steelcase Leap

When I sat in this chair for the first time it felt like an ‘old faithful’, like a chair I had sat in for a number of years—quite comforting. I think this would be down to the padding used. This chair felt NICE.

RH Form Logic 400

This chair is instantly different to the others. For a start it looks like something out of an Ikea catalogue—all angular and 90’s ‘modern-art’ skinny; not like the current executive trend for big and wide. This chair is obviously not designed for the American Executive market, which may explain why RH Form have only 50% of sales outside of Sweden. Secondly, the chair is made of what appears to be normal foam—just like an Ikea chair in fact. Thirdly, this chair is very upright and firm. It felt like a chair designed for somebody with a bad back. It felt like something my chiropractor would have designed—SENSIBLE.

Setting up

This is all about adjusting the chair for my perfect fit.

Herman Miller Aeron

1. Set the seat height
2. Set the tilt tension
3. Set the armrest position
4. Set the amount of lower back support

Controls are logical and intuitive. All very simple really. It is really easy to get the right amount of tilt-tension—the adjuster is fingertip light and very sensitive.

Humanscale Freedom

1. Set the seat height
2. Set the seat depth
3. Set the lumbar position
4. Set the armrest position
5. Set the headrest height

This chair’s big selling point is the fact you can’t adjust the tilt-tension—it automatically sets the right tension based on your body weight. All the controls are straightforward to use and intuitive.

Steelcase Leap

1. Set the seat height
2. Set the seat depth
3. Set the tilt tension
4. Set the lower back firmness
5. Set the armrest position
6. Set the lumbar position
7. Set the amount of curvature under the thigh

Again, all straightforward to setup, especially as there is an interactive Flash presentation on the company’s website.

RH Form Logic 400

1. Set the seat height
2. Set the seat depth
3. Set the back to seat angle
4. Set the lumbar position
5. Set the tilt tension
6. Set the amount of lower back support
7. Set the armrest position
8. Set neck rest position.

This chair was the hardest to ‘understand’ how to setup, because the tilt tension is dependent on the back-to-seat angle, so when one is adjusted the other needs to be adjusted too. The other chairs don’t have this problem—but only because the other chairs don’t have a back to seat angle adjustment. Also, because the tilt-mechanism is so sensitive, the tilt needs to be locked before any other adjustments can be made. Again, this isn’t a criticism and once used to this procedure, it becomes logical and intuitive. What is a problem is the tilt tension control is on the left side, and is quite stiff to operate and requires a large number of turns to get right. I would imagine anybody with arthritis may have a problem setting this adjustment.

The Interview Test

I’m spending two days interviewing candidates for a technical support role, so this is a good test of each chair in a non-computing environment.

Herman Miller Aeron

This chair worked well. I could set the tilt adjustment to give me a nice rocking motion, and the arm rests worked well. Best of all was the posturefit lumbar support—it is impossible to slouch in this chair. And, I felt like the boss in this chair. After all, it is probably one of the most famous chairs in history. Slightly annoying though is a small squeak every time I rocked. Not so good for such an expensive chair. I got though all the interviews without problem, and would be very happy to use this chair again for this task.

Humanscale Freedom

I sat in this chair for one interview, stood up, and had to hold my lower back. This chair had killed my back—in half an hour! The problem is the complete lack of lower back support. In the upright position, the lumbar support is in contact with my back, but as I recline (and it is hard not to, as there is no locking mechanism), the lumbar support leaves contact with my lower back meaning I have no support whatsoever. The only way to fix that is to stand up and shuffle back in the seat so that contact is made again—but by doing that my head is now higher up the seat and I need to readjust the headrest. Things get worst when I move from the reclined to an upright position—as I do that the friction between my clothes and the seat back causes the seat back to rise up it’s ratchets—meaning I need to readjust the back height after every reclination. I honestly cannot believe how bad this chair is. I really wanted to like this chair as I liked the look, and the fact it has a decent headrest, but this chair is out. I just hope my back recovers and I don’t need a trip to my chiropractor.

Steelcase Leap

This chair has a similar problem to the Freedom—when I recline the support I get in the lumbar region is reduced. After an hour sitting in this chair I couldn’t stop fidgeting. Imagine flying to Australia in British Airways World Traveller (or Club World for that matter) and you’ll get the picture. The problem is the chair doesn’t tilt. As you recline the back, the seat moves backwards and forwards, but doesn’t tilt (rather like a Club World seat actually). This just feels uncomfortable. But, the biggest issue I had with this chair is that the recline locking-mechanism is on a ratchet which emits loud clicks as you twist it. Not good in an interview situation.

RH Form Logic 400

The tilt and rotate mechanism on this chair is so light it’s as if you are floating on air. Now that’s good, except I had to lock the chair because in free-tilt mode I couldn’t stop rocking and tilting like a crazy person. I didn’t want the candidates thinking they were being recruited by someone so wired up on caffeine I couldn’t sit still. However, there are four apparent problems with this chair.

1. Although it encourages you to twist and tilt, your back is kept rigidly in position by the very firm back. I wanted to stretch my back after just 45 minutes in this chair, but had to stand up to do that.
2. Although the neck rest kind-of works in the reclined position, it is in the way in the upright position. Unlike the Freedom, where the headrest moves out of the way in the upright position, the Logic 400 required constant fiddling with the headrest depending on my seating position. And the headrest mechanism is flimsy and several times I ended up with the headrest in my hands and had to stand up to refit it.
3. The foam padding doesn’t work as well as any of the other seats (bar the Leap). I started to get a numb bum and could feel quite a bit of pressure on my Coccyx area after just an hour.
It doesn’t feel like a chair fit for a CEO. The neck rest looks silly, and it looks like a task-chair rather than an executive chair.

The Computer Test

Onto 12 hours of straight VB.Net development now. This will be each chair’s toughest challenge yet.

Herman Miller Aeron

Unfortunately this chair didn’t perform anywhere near as well as it did in the interview test.

1. The armrests cannot be moved backwards, meaning to get close enough to the desk they need to be lowered completely—meaning they are completely useless and may as well not be there.
2. The mesh material is quite hard after a few hours of use—leading to unconscious fidgeting and general discomfort. It’s the sort of discomfort that isn’t immediately apparent, not like something digging into you, but it definitely distracted me from my programming. I have on occasion had a leg go numb, and I feel some parts of my body become unusually warm (like pins-and-needles are not too far away).
3. When the chair is locked, there is a lot of play in the gas-lift mechanism, meaning the chair still rocks from side-to-side a few millimetres. This is quite annoying, even more so when I think of the price tag.
4. When pondering a problem I like to lean back away from the keyboard and monitor. This chair does not have a head or neck rest, so it is not that comfortable in the reclined position for long periods of time.
5. In it’s favour, it is impossible to slouch in this chair and after 3 months of using this chair I have had no back problems whatsoever.

Humanscale Freedom

Following the appalling interview test, I didn’t have high hopes for this chair, and I wasn’t wrong. I had to give up after ten minutes. Not only did I have severe lower back ache, but I got an itchy bottom from this chair as well (No I wasn’t commando, yes I was wearing Levis…).

In it’s favour I loved the quick-adjust armrests (maybe because I ride an R6 and the twist-grip mechanism to lower the armrests is like cranking open the throttle). I appreciate the counter-balanced auto-recline feature as an engineering work of art, but it just doesn’t work in real-life.

I would say that when I sit in this chair only it it’s reclined position, with my feet propped up on the Aeron, this chair is reasonably comfortable. This is actually quite interesting, because Humanscale sell a matching footrest and their website makes a point that many users like to prop their feet up. Unfortunately, in my office a Lay-z-boy would be more practical than requiring a footstool.

Steelcase Leap

I tried for an hour to adjust this chair, but I couldn’t get it to fit my body shape. It just doesn’t work for me. I suspect the tilt mechanism (designed to keep your eyes level and your arms at the same fore/aft position through all levels of recline) is the culprit, and the lumbar support (a silly plastic strip you need to raise and lower, that doesn’t actually seem to have any effect) is no where near as good as the Herman Miller posturefit system. To bring the chair from the reclined position to the upright position requires quite a lot of effort—it isn’t sprung. The technique is not so much to bring your back upright, but in addition to slide your bum backwards.

For computing work this chair does not tip forward past neutral—which in my opinion makes it unsuitable for I.T. work. The chair also felt clinical—it has lots of ‘engineering’ touches like instructions printed under the armrests, but I don’t want my chair to feel clinical and engineered, I want it to feel cosseting, and the Steelcase Leap just doesn’t achieve that. This chair is too much BMW and not enough Alfa Romeo. Plus the fact it is just damn uncomfortable.

RH Form Logic 400

For I.T. use, this chair fits my desk best—probably because it is so skinny and small. The arm rests can be moved completely out of the way by swivelling each 180 degrees, providing an elbow perch while the weight of my arms is carried on the desk. The chair is very upright—which is supposed to be a good position for typing (although not the sort of position you would contemplate having a snooze), and the light-as-a-feather rock-tilt motion is fun. However, for serious amounts of coding I found the motion distracting, and prefer to work with the chair locked.

There are five main problems with this chair:

1. I get a numb bum. I don’t think the cushioning disperses my weight too efficiently.
2. In the reclined mode, I get too much pressure on the Coccyx.
3. The rock-solid back rest prevents my back from moving, so I get a stiff back quickly and need to stretch. To do this I actually need to come away from the chair.
4. When in free-tilt mode, there isn’t enough backward recline. Whereas the Herman Miller reclines a looooong way, becoming progressively stiffer the further back you tilt, the Logic stops with an abrupt bump a lot sooner than you would imagine.
5. This chair is Ugly. It looks like a cross between a dentist’s chair and some modern art type furniture from Ikea, but with a gall-bladder hanging out one side (the air lumber pump).
6. In it’s favour, I love the locking mechanism. Rather than being a ratchet, with a set number of locking positions, it is a friction knob—meaning you can set the tilt exactly where you want it. It only requires a quarter turn, and is a pleasure to use. It is also silent, unlike the Steelcase Leap, and also the Aeron (which emits a small click).

Conclusion

Well it’s obvious the Humanscale Freedom has to go, purely on the grounds of back health. No matter what positions I tried, I got severe lower back pain within half an hour. I had high hopes for this chair based on web articles, so it’s an even bigger disappointment that it didn’t perform.

Also to go is the Steelcase Leap. It has obviously been designed and engineered with pride but the fore-aft seat movement rather than the proportional tilt of the Aeron and Logic 400 doesn’t work for me, plus the lack of forward tilt means it isn’t suitable for intensive keyboard work. I also couldn’t get enough lower back support in the reclined position, and after an hour the chair felt uncomfortable.

That leaves the RH Form Logic 400 and the Herman Miller Aeron. Both very different chairs in every aspect. The Herman Miller is an icon, a status symbol, and despite the price tag is pretty badly put together (it squeaks, an arm rest was floppy, and the gas-lift is rickety). In contrast the Logic 400 is virtually unmentioned on the Internet, it looks like something out of Ikea and it has a silly neck-rest. That said, it has a superb tilt mechanism and feels the best put together of all the chairs.

I don’t think either the Logic 400 or the Aeron are perfect—the Aeron isn’t suited to I.T. work due to the arms, and there is something about it that makes me fidget after a couple of hours, and the Logic 400 is at the other extreme—it holds my back too firmly in place and it has poor cushioning.

So which would I buy?

Well the truth is I bough an Aeron 3 months ago, but was unhappy with it, hence the reason for testing the other chairs. From this bunch the only chair to give it a run for it’s money is the Logic. I love the tilt mechanism and build quality (apart from the silly neck rest), but for long periods of sitting I find a genuine Ikea chair (their top of the range Operativ) more comfortable than the Logic 400 as I don’t get a numb bum. But the Ikea chair doesn’t give anywhere near as much back support as the Logic 400, which is the other extreme and borders on rigour-mortis.

My conclusion is none of these chairs is my ideal chair, and therefore I need to keep looking. But it has been an interesting exercise and I have learnt the following:

1. Don’t believe hype, or anybody else’s word on what is a good chair. You must try for yourself.
2. A half-hour test in a showroom is not long enough. You need to try the chair in the environment it will be used.
3. I like a chair with a seat that tilts in proportion to the back rest. I don’t like chairs where the seat is fixed, or moves backwards and forwards.
4. The ability to position armrests out-of-the-way when working on a computer is essential.

With this in mind, I am now going to arrange demos of the new Herman Miller Celle (which has an improved tilt mechanism over the Aeron, and a new cellular structure that may stop my fidgeting) and the RH Form Moveon, which has a hinged back that may reduce back stiffness and allow me to stretch. Watch this space.

Notes

Physique is an important consideration when choosing a chair. I am 6 foot and (before I got married) had a 32" waist.