Saddle chair
en.wikipedia.org
en.wikipedia.org
* It doesn't force you into a straight-back posture, but it makes it as easy as slouching. If you stop concentrating you don't fall into a poor posture.
* There's really only one way to sit on the chair, with your sit-bones taking most of the pressure. In a normal office chair I can switch between a set of different slouches to move the pressure between points, but not with this chair. I bought a height adjustable desk to compensate and switch between sitting and standing several times a day.
* It takes a fair amount of strength. I don't remember if it took me time to build muscle initially, and on a day to day basis I don't notice any tiredness or anything, but when I'm sick it is _really_ hard to sit on this chair - I feel like I'm going to pass out (maybe not to that extent, but it's quite noticable).
* I bought the first one for $800, but AFAICT they've come down to $300ish this year maybe due to competition. They're sturdy and really nicely built, but in the end it's just a stool with some curves.
* May or not be related, but I found my back getting really stiff because it is literally straight all day - sleeping, standing up, sitting on the Salli chair, etc, which worries me a bit.
* You sit at a much higher level than with normal chairs, so you'll need a higher desk to accommodate.
Do you stretch?
Also, the expensive models are made in Finland while the $300 models are made in China for the outside-EU market.
You should vary your position regularly (every hour, for example). The simplest solution for this is a desk where the height can be changed easily (maybe with a motor), so one can sit for a while, then stand for a while, and so on.
I only had to use the 'bad' chair because the good ones - with a proper foot rest - had been snagged.
Also, I have an extra Salli Twin I use while cooking and doing dishes in the kitchen.
It's a fascinating analysis of how chairs impact posture and the related biomechanics. It shows why oft-touted "lumbar support" does more harm than good, how attitudes to chairs and posture are affected by cultural expectations, and why there is no perfect chair, but with recommendations for how different chairs manage different tradeoffs -- she ultimately most highly recommends high stools which allow the body to maintain a 135° angle with full foot support -- which the saddle chair accomplishes.
[1] https://www.amazon.com/Chair-Rethinking-Culture-Body-Design/...
The nice thing about Capisco is there are quite a few ways to sit on it so you end up using different muscle groups during the day rather than constantly using just one. You need a height adjustable desk to pair it with this chair.
The only "ergonomic" chair I've ever like is another chair by Capisco's designer, Peter Opsvik, called Balans, now made by Varier [1]. It's a kneeling chair that rocks and supposedly forces you to exercise your core and maintain a good posture. It's fairly expensive ($400) for such a simple piece of wood, but you can find cheaper used ones on eBay.
Opsvik designed some crazy chairs. My favourite crazy chair of all time is his Globe chair [2]. The Gravity Balans is also weird, but probably great.
[1] https://varierchairs.com/product/variable-balans/
[2] https://www.ignant.com/2015/08/27/globe-furniture-by-peter-o...
[3] https://hiconsumption.com/2013/03/reclining-gravity-balans-c...
They look awkward to sit on, you actually have to try them to realise you naturally adopt an upright (not slumped) sitting position.
I also just found some plans, might make one so it's adjustable my way: http://www.craftsmanspace.com/free-projects/kneeling-chair-p...
e.g. https://www.varierfurniture.com/en_gb/explore-our-chairs/kne...
Opsvik was partly responsible for the wave of interest in ergonomic seating in the 1980s. He eventually wrote a book, Rethinking Sitting [2], about the topic.
[1] https://varierchairs.com/product/variable-balans/
[2] https://www.amazon.com/Rethinking-Sitting-Peter-Opsvik/dp/03...
Another product that was moved over to the Balans brand was the Move chair by Per Øie [1], which is an actual saddle chair.
[1] https://www.archiproducts.com/it/prodotti/varier-furniture/s...
From what I understand (and years of use) they merely place a small amount of weight on the front of your shins, which is at most merely uncomfortable for some people. (Most of your weight should be supported by your bottom.)
For an average human body, I have a hard time imagining what biomechanics could lead to a knee issue from it? A quick Google search didn't show anything.
You still can slouch in the saddle especially if you don't have an elbow support or if your table is not tall enough. If your arms are not in a symmetrical position during the day, e.g. if you are a frequent mouse user, spine would tend to curve to the side of the hand that is further from the center. This can result in scoliosis.
Would I recommend one? Yes, if you have blood flow problems.
I noticed that if I'm doing exercises I can seat on whatever comfortably save for the bloodflow issue.
That worked great in a setting where I was going and coming to my desk frequently and having to show stuff to others (beats making people bend down to watch a screen). Since then, that desk has moved to my home office and a few months ago, I adapted it to a sitting position but for a desk height that sits midway between a regular sitting desk and a standup desk. I still enjoy it for all-day work.
However, at the risk of stating the obvious, NO CHAIR is suitable for 8 hours sitting down. Regardless of your setup, getting up and taking breaks is necessary. Go for a little walk: both your back and your mind will thank you. Even better: do some stretching exercises during breaks—a goal I aspire to but haven't yet trained myself to do on a consistent basis.
Though
"A divided seat reduces pressure on the perineum and lowers the temperature in the genital area. A divided seat is thought to be healthier, especially for men, than a solid seat."
Is it healthier, is there any evidence for that?
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