"But it has no back!" you exclaim the first time you see a kneeling chair.
Kneeling chairs have been the source of much controversy in the world of ergonomics. Are they some Japanese thing? Are they a gimmick? How do you even sit in the thing? Some organizations have classified them as orthotic devices. Some ergonomists have written them off entirely. Yet we are still left wondering, do kneeling chairs work?
The key to answering this question is first to ask, "how does the body work?" Fortunately, we only need to understand how one important set of joints affects the rest of the body--the hips.
Biomechanical studies have revealed that the the thigh bone is only capable of rotating up about 60 degrees in the hip joint. After the math, this leaves us with another 30 degrees we still need to raise our legs in order to fit into an ordinary 90 degree, right-angled chair. Obviously we sit in chairs every day, so how do we do it? After the hip joint maxes out, we rotate our pelvis backwards in order to get the extra contraction we need to fit into a chair.
Therein lies the problem with a standard chair. It's impossible to sit truly upright with your pelvis tilted backwards. Rotating your pelvis backwards points the natural head spine line behind your chair back. However, the chair back prevents you from leaning backwards into the natural head-spine line, and forces your spine upwards in a way that stretches and pulls on the lower back. This leads to the "flat lower back" that causes low back pain and ruptured discs. Ouch! Standard ergonomic chairs try to fix the problem by restoring the curve in the lower back with lumbar support. But lumbar support can't fix our postural woes, because the problem is not the lower back! The problem is that our pelvis is tilted backwards.
Enter the kneeling chair. Most kneeling chairs are built at a fixed angle that only raises the thighs 60 degrees--as far as the hip joint naturally allows. This allows your hips to stay in their neutral, upright position. Without the pressure of your pelvis and chair back fighting each other, sitting upright becomes very easy. So easy, that you don't need the added force of a chair back to keep you upright.
Many people (including myself) have even adopted kneeling chairs as office chair replacements for our regular 8-10 hour days of office sitting without missing the back at all. The only caveat for a new user is that your lower back has been weakened by years of using a regular chair, and there will be an adjustment period while your lower back muscles come back into balance with your abdominal muscles. Alternate sitting in your regular chair and your kneeling chair for the first week or two while you are getting used to the new chair. Don't just switch cold turkey.
So the final decision, do kneeling chairs really work? Once you get past that they "look weird" and don't have a back, the answer is an enthusiastic "YES!" They are both scientifically and experimentally proven to be among the best ergonomic chairs because they fix the real ergonomic problem with chairs--hip angle. Replacing your regular chair with a kneeling chair is likely to boost your energy, reduce daily pains and fatigue, and provide the added postural benefit of walking taller and prouder than you ever have before.
No comments:
Post a Comment