Chairs -- History, Design, etc.
This is a recording of Robert Rickover in conversation with Galen Cranz, Professor of Architecture at the University of California, Berkeley. She's the author of a book called [I]The Chair[/I], and good to hear her speaking here.
Interestingly, she says it turns out that chairs are older than has been believed, there being archaeological evidence for then going back as long as 10,000 years ago. Of course, that's a blink of the eye in evolutionary terms. Also, she points out that chairs were originally status symbols. There were very few of them around; and most people did not start using them, even in industrialized countries, until 200 years ago (at a very generous estimate). And in this connection, she comments note the words "chairman" and "board".
There's much also on the design of chairs and the problems they cause. I was familiar with much of this, but what's new to me here is the discussion on [I]angles[/I]. She points out that when a person is seated in a chair the hip is at a 90 degree angle, and that, she says, tends to put more pressure on some crucial vertebrae. Interestingly, she comments that NASA found that in weightless conditions people fold up to a midrange (something more like 120 degrees, IIRC), which probably indicates that that kind of angle is less of a strain.
So far as positive recommendations go, she says she likes high barstools. If you're up on one of those, the knees can be lower than the hips, which is a better position. Also, chairs have [I]square[/I] tops -- which hold the thighs up and in a fairly set position. With a barstool, the thighs can drop round the top and down, and there's also more room to sit in slightly different ways -- holding the same position is not good.
She quotes an intriguing comment from someone to the effect that the next position is always the most comfortable one. It's a way of saying that any position can be uncomfortable if held too long. Ideally the sort of working conditions where we could move between different types of seating, stand for periods, and even take a few minutes to lie down (note: as hunter-gathererers do) just for a short while very occasionally would be best for us. She says imagine an office with a kind of "circuit" of different workstations where people could move between set-ups rather than being stuck in [I]one[/I] physical relation to their work all day. And when you realize how far out that would be from what most corporate cultures would stand, or even evisage, you see the size of the problem.
Much more here:
[url=http://bodylearning.buzzsprout.com/382/47272-an-alexander-technique-perspective-on-user-friendly-chair-design]An Alexander Technique perspective on user-friendly chair design[/url]
Oh, I'll just add, Galen Cranz says that back when she first wrote the book there were a lot of people running around saying that people have trouble with their backs because nature didn't get the "design" quite right, and we were sort of half-evolved from quadrupeds. She said she was one of the first people to say that actually chairs are one of the reasons what people get back pain. (I don't think that is so unusual a recognition these days.) So, no, we're set up to work pretty well; it's what's we do to ourselves that cause the problem. I think that's spot-on. Nature, in my view, doesn't blunder, and I think organisms are generally pretty finely tuned to their environments.
I would add, though, that I think people that deal with, and think about, human movement a lot probably miss the extent to which we can jigger ourselves up not just by our habits of movement but by diet. I think Pottenger's experiments with the cats show that: by malfeeding cats for a generation or two, Pottenger could cause their physical proportions, balance, reactions, etc. to get screwed up. He did experiments like holding the cats upside down and dropping them: a healthy cat can right itself, but one that he'd mal-fed (perhaps over generations, causing what we'd now call epigenetic damage) might not be able to.