Sounds great, doesn’t it? A little scientific, even medical (“lumbar” from the Latin lumbus, meaning loin). And at the same time gently comforting; who doesn’t love “support”?
If you’re going to sit at your desk all day, answering email or slaving over some code or a spreadsheet, aren’t you going to need some support? Heck, don’t you deserve some support? Makes perfect sense.
But while this story line has been widely circulated, it’s just wrong.
3 million years, and now we need support?
First of all, why would you need lumbar support? We humans have pretty much had our current spine design for about 3 million years, so doesn’t it seem odd that we suddenly need lumbar support? And strangely, we only need lumbar support when sitting; somehow we don’t need lumbar support when standing, walking, or lying down.
What’s going here? Well, it turns out that sitting in a conventional chair distorts the spine so it requires support.
90/90/90 = bad posture
Here’s the scoop: when you’re sitting in a conventional chair (like a typical “ergonomic” office chair), you likely have your thighs parallel to the floor… ankles at 90 degrees, knees at 90 degrees, and hips at 90 degrees, just like in the books and promulgated by ergonomics experts for decades. Like this:
Caption: 90/90/90, as shown here and promoted by conventional ergonomics, is uncomfortable and unhealthy for your back.
Unfortunately, “90/90/90” is a terrible way to sit. Your hip can’t flex past about 60 degrees without causing the spine to lose its normal curve (lordosis), which produces the “hollow” of your low back when you’re standing comfortably.
Caption: Standing allows your lower back to curve inward, naturally. This curve flattens out as you raise your knees. When your knees are at 90 degrees to your hips, it is impossible for your spine to produce this curve naturally. “Lumbar support” in conventional chairs, is an attempt to force this curve.
Because this “90/90/90” position forces you to hunch your lower back, the standard office chair adds “lumbar support” that shoves your lumbar spine forward – a vain attempt to recreate the spine’s normal posture.
Lumbar support: a bad fix to an unnecessary problem
To sum up: the standard office chair first distorts your posture, and then tries to “fix” the problem by further distorting your posture with lumbar support. Crazy! No wonder people hate their office chairs, and no wonder 80% of Americans have low back pain.
Trying to impost posture on the spine by pushing on it is utterly misguided. Really, your spine wants to adopt its naturally perfect posture – there’s no need to force it. And in fact, simply lowering one’s knees below one’s hips restores the normal lumbar lordosis automatically.
The mechanism is a little technical, but surprisingly simple: the psoas muscle originates on the five lumbar vertebrae, travels over the inside of the pelvis, and then attaches to the femur. This arrangement ensures that when one lowers the knees, the femur gently stretches the psoas muscles and thus restores the normal lumbar lordosis.
A simple fix
Raising your chair high enough so that your knees are lower than your hips will improve your posture enough that you won’t require any artificial “lumbar support”. It’s why we designed the QOR360 chairs in a variety of heights, and why the chair is more comfortable without a back.
Caption: Raising the seat of your chair so it is above your knees allows your hips to open, and the curve of your spine to return, naturally. See our measuring guidelines to see how high the seat of your chair should be.
We sit on average for 10 hours a day, so it’s important that we have chairs that are comfortable, and which don’t damage us. Sitting without conventional lumbar support can actually, well, support your lower lumbar lordosis and promote good posture, even better.
-Dr. Turner Osler
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