| How can you produce your best work if you are | | | | versions of the sloping seat were:- |
| sitting in an uncomfortable chair? | | | | You tended to slide forward. |
| Do you get niggling pains in you lower back? your | | | | Too much weight was placed on the feet. |
| neck? Or your shoulders? Maybe its time to look | | | | Your clothes tended to 'ruck up'. |
| more carefully at the chair you are sitting on. How | | | | Forward-sloping kneeling chairs were produced to |
| is it designed? | | | | incorporate Mandal's suggestions - using a knee |
| For several hundred years there was no change | | | | rest to prevent slipping forward. Most of the |
| in the basic design of the conventionalchair. The | | | | weight is taken on the knees and while this |
| seat was set at a 90 degree angle to the | | | | reduces pressure on the discs, the muscles had |
| backrest – an ‘L’ shape. | | | | to work harder to maintain an erect posture |
| Some of the early additions to the standard chair | | | | when there is no backrest. As your muscles |
| for use in offices were:- | | | | become tired there is a natural tendency to |
| A swivel action which allowed the user to swing | | | | slump. |
| around – maybe the designer was fascinated | | | | In addition to these problems your knees and |
| with merry-go-rounds! | | | | shins can become quite sore after a time since |
| Next there was the wonderful up and down | | | | there is no provision for changing the knee |
| action of the hydraulic lift. People of short stature | | | | position. Getting in and out of the chaircan be |
| had to come up with a footrest of some sort if | | | | somewhat difficult because of interference from |
| they wanted to be relativelycomfortable at work. | | | | the central pillar. |
| A common drawback of these devices, at least in | | | | Despite the various drawbacks mentioned, |
| the early days, was that the gas leaked from the | | | | however, many thousands of these chairs were |
| system and then the seat “let you down”. | | | | sold because of the obvious relief given to the |
| A further addition to the “office chair” | | | | discs through the forward-sloping seattaking |
| was the provision of armrests. | | | | pressure off the spine. |
| It was not until the 1970s that a major change to | | | | Kneelsit Balance Chair |
| the basic ‘L’ shape of the office chair | | | | When you allow the seat pan to tilt forward your |
| came about through the studies and research of | | | | pelvis rotates forward, this posture produces the |
| a Dr. A.C. Mandal in Denmark who was one of the | | | | least amount of stress on muscles, tendons and |
| pioneers in proposing the benefits of a | | | | discs, since your spine iscorrectly aligned. It also |
| forward-sloping seat. Dr. Mandal had found that | | | | pulls the chest out, increases lung capacity and |
| the only way he could remain seated without | | | | makes breathing easier as well asimproving the |
| incurring backpain was to leanforward on the | | | | working of the heart and blood circulation; it also |
| front legs of his chair. He also observed that | | | | allows you an open abdomen, which aids digestion. |
| many school children did the same thing when | | | | When your pelvis is tilted forward your lumbar |
| trying to ease back pain brought on by poorly | | | | spine curves naturally and the rest of your spine |
| designed school furniture. | | | | follows. This is the ideal posture when working |
| Mandal recommended that the seat pan should | | | | upright - as at a computer. Whenyou have a |
| slope forward by 15°. When we take up this | | | | backrest - as in the Kneelsit chair - this backward |
| position our lumbar spine does not need to flatten | | | | tilt can also be used to relaxthe spine and take |
| out to assume the seated postureand our hips | | | | pressure off your disks and muscles, for example |
| and trunk are at the optimum position of balance | | | | when you are reading or just chatting. |
| for the muscles. | | | | The real secret, however, to maintaining a healthy |
| By tilting your seat forward you alter your centre | | | | spine is to have a chair which allowsfree-flowing, |
| of gravity from behind the sitting bones (ischial | | | | natural movement between both forward and |
| tuberosity) to directly above them. As a result | | | | backward tilts. This sets up a continuous "pumping |
| your muscles do not have to tenseup or contract | | | | action" which feeds and nourishes the cells of |
| to maintain an erect posture. At the same time | | | | your spinal discs,exercises your back muscles and |
| the lumbar curve ( or lordosis) is restored and | | | | allows you to sit for hours on end with very little |
| pressure on your discs is reduced. | | | | discomfort. |
| Some of the more common objections to early | | | | |