IMROVED POSTURE and LUMBAR SUPPORT in a COMPUTER CHAIR
1. The Foundation of good posture in a Computer chair - a Sloping Seat!
Dr A. Mandal in Denmark in the early 70's outlined the advantages of a forward-sloping seat in improving your comfort and posture when he discovered that the only way he could stay sitting without experiencing backpain was to brinfg his weight forward to the front legs of his chair. He also noticed that a lot of students used the same trick when trying to relieve their back pain.
Mandal found that if the seat pan sloped forward by 15°.this aided greatly in making for greater comfort since if you take up this position the lumbar spine doesn't have to flatten out to assume the correct posture and your hips and trunk are placed in an optimum position of ieal balance. Furthermore your muscles anmd tendons are not forxced to become tensed up or contracted to maintain an erect posture. At the same time your lumbar curve ( or lordosis) is restored and pressure on your discs is reduced.
There were a number objections to early versions of the sloping seat such as a tendency to slide
forward, your clothes tended to bunch up and there was too much pressure on the knees.
In the late 70's and early 80's there were various forward-tilting chairs made which incorporated Mandal's suggestions. They used knee rest to stop you slipping forward. so that most of the weight was taken on the knees and while this remedy reduced the pressure on your spinal discs, you had to concentrate on working harder to keep an erect posture since as there was no backrest your muscles became tired so there was a tendency to slump. In addition to sore knees and shins there were difficulties in getting in and out of the chair because of the central pillar.
Despite these various drawbacks mentioned, however, large numbers of these chairs continue to be in demand because of the relief from back pain brought about by the forward-sloping seat taking pressure off your spine.
The Kneelsit balance chair was designed and produced without the "benefit?" of having any of the knee stools as a model, rather the old Masai camp stool and the angle it brought about in the thighs and trunk were our benchmark. Your spine is correctly aligned because that is how it worked out in the early trials of making the first prototypes. Sitting in this manner tends to pull your chest out and so increases lung capacity making breathing a lot easier.
When your pelvis is tilted forward your lumbar spine curves naturally and the rest of your spine follows. This is the ideal posture when working at a table or desk. Kneelsit chair has a backrest so leaning back allows you to relax your spine and so relieve the pressure on your intervertebral discs.
Using the Kneelsit chair distributes pressure (or compressive force) from your spinal column to your thighs and lower legs easing the strain on your muscles, joints and tendons as well as your intervertebral discs and associated nerve endings which combine to hold your back upright. The forward sloping seat opens out your thigh/trunk angle and works together with the reduction in spinal pressure to bring about a significant improvement in posture.
Your sense of "relaxed awareness" and improved postural
position operate in conjunction with the "balance effect"
to bring about a more equitable distribution of work load to all
relevant parts of your musculo-skeletal system instead of allowing
your muscles, discs, tendons etc. to be subject to the continuous
strain of flexion.
Excellent lumbar support is provided in the kneel-sit chair by a backrest which adjusts both vertically and horizontally to suit a very wide range of body sizes.
" - i injured my back flying military jets and have trouble
sitting for long periods of time due to sciatica and disc/muscle pain....the
equipoise takes the weight off my tailbone and shifts the bulk of my sitting
pressure to my shins and lower rear.....it also enables me to sit up straight
and maintain posture because of the adjustable back support .... i swear
by it. Feel free to use my name and email address."
Adustable Seating P.O. Box 253 KIAMA N.S.W. 2533 AUSTRALIA