Tuesday, February 22, 2005

Ergonomical office chairs

Office Chair Ergonomics may seem like a mystical subject, what with the dizzying array of levers and knobs appearing on office chairs nowadays. Yet this subject promises to relieve us from back pain, carpal-tunnel, and other stress symptoms. The basic idea is this: there are zillions of us office dwellers, sitting in chairs all day long while our bodies were designed by evolution for running, jumping, digging in the dirt, climbing trees, and much more. We've found through study that proper posture is a good thing, and that improper posture damages the back or arms.

A good ergonomic office chair helps you keep good posture through proper support that guides your body into a good position. In the resources section are pointers to several articles that explain this in more detail. The adjustability discussed are up-down, lumbar support, adjustable armrests, and more.

One thing to learn is that a "mesh" chair doesn't automatically mean its ergonomically correct. Using a mesh fabric for the seating surface was a design choice by Herman-Miller in the Aeron chair, and the ergonomic features (lumbar support, etc) were a separate issue from the choice in seating surface.

Another chair frequently said to be "ergonomic" are the kneeling chairs. These have two cushions, one for your legs to kneel on, and the other for your buttocks, and neither of these cushions are horizontal. Often these have no back support, and the idea is that the sitter forces themselves into proper posture or else they quickly are very uncomfortable.


Herman-Miller Aeron: (hermanmiller.com/CDA/SSA/Product/0,1592,a10-c440-p8,00.html): I've sat in this chair for a short stint in a Design Within Reach store. It is a cool looking chair, no doubt about it. It has all the adjustability one would want for ergonomics and proper back support. My only qualm is that the seating surface felt very hard. The seating surface is a cloth-mesh that stretches to match your body, but once it stretches it has no cushioning. Otherwise it is a very good chair, very well built, it does a great job of being ergonomically correct, and it looks great.

Herman-Miller Mirra: (hermanmiller.com/CDA/SSA/Product/0,1592,a10-c440-p205,00.html) Very similar in shape and appearance to the Aeron, also from Herman-Miller. It has the same sort of ergonomic controls. Rather than a mesh surface, the seat is a cushion, and the back is a plastic mesh. One interesting feature of this chair is that every part is recyclable, and marked for recyclability, and the chair can easily be taken apart.

Herman-Miller is the "Apple" of the furniture industry, by which I mean they start first with stylistic artistry and then work to make sure the functionality is great.

Freedom: (humanscale.com/products/freedom_index.cfm) This is an interesting chair with unique features that set it apart from other office chairs. The concept is that bodies like to move, so the chair should take that into account. For example the back does not lock into place, but lets you lean back freely and easily. Now, if it simply let you lean back that wouldn't be so good, but as you lean back the chair automatically adjusts itself to still provide proper ergonomic support, so that the chair supports you no matter what you do. Also if your Freedom chair has a headrest, the headrest also automatically adjusts as you lean back to properly support your head. Another feature is that structural arms in the chair do not "cut" across your body, but instead they are situated lengthwise along your body. They claim this improves, or rather does not impede, blood flow in your body.

Relax the Back: (relaxtheback.com/) This company specializes in ergonomics and products that support the healing of conditions such as back pain. Among their products are a line of office chairs. I recently went to their store in San Jose (CA) and tried a couple chairs. The most interesting of them looked like a typical boring office chair, unlike the fancy and stylish chairs from Herman-Miller and Humanscale. All of the ergonomic adjustability features were present in this chair, plus the cushioning material was "memory foam". If you've tried a Tempur-pedic bed, then you know what memory foam is. The basic idea of memory foam is it is a rubber foam that compresses to shape itself to your body, then returns to its original shape, and when someone else sits on the foam it compresses to their body shape, and for each person that sits on the foam it shapes itself to each unique body shape. The memory foam made the Relax the Back chair feel like it was embracing me in comfort.

Haworth TAS (haworth.com/furncat_new2000/index2.cfm?cid=7&misc=cover): Another unique chair in the same vein as the Freedom chair. In addition to embracing the fact that we humans like to move around, the TAS is structured to assist you in side-side movements.

BodyBilt (bodybilt.com/): They offer a line of chairs that are said to provide "zero gravity" seating. What this means is the seat cushions are preshaped to cradle your legs, presumably to provide more complete support.

Equipoise: (kneelsit.com/index.html) A kneeling chair that includes a backrest.

Ergopro (ergopro.com/): Offers both products and information on their web site. They offer several chairs.

Kinesis (kinesis-ergo.com/products.htm): Offers several ergonomic products, including office chairs.

First Ergo (1stergo.com/): Another merchant of ergonomic products, including several office chairs.

Butt Pillow (http://www.buttpillow.com/): A seating cushion you can add to any chair that does good things for your butt.


Choosing the right ergonomic office chair (spine-health.com/topics/conserv/chair/chair01.html) Recommendations on the characteristics of a good and ergonomical office chair.

Office chair setup and use (healthycomputing.com/office/setup/chair/) Recommendations on setting up whatever chair you have for the best ergonomics. They also have a buyers guide.

DeMystifying all those chair adjustability options (office-ergo.com/ergonomic_seating.htm): Explains the features of ergonomic chairs, and why they exist. The office-ergo.com web site is full of good general ergonomics information.

Sitting postures and seating (humanics-es.com/etc.htm#Sitting): Several articles covering ergonomic seating, and part of an extensive website published by an ergonomics consulting practice.

Office Chairs reviews (consumersearch.com/www/office/office_chairs/fullstory.html): This is a summary of office chair reviews collated by Consumer Search on several ergonomic office chairs.