Doctor's Casebook with Dr Keith Souter: Are you sitting comfortably....

So much of modern work is done on a computer, which means sitting down in front of it for hours at a time.

That work position may not be ergonomically suitable and back pain can be the result of it. Sitting has a big impact on the back.

Sitting puts 90 per cent more pressure on the lower back than does standing.

With regard to the spine, one effect of sitting tends to make you lose the three curves in the spine that are so obvious when you are standing.

They get replaced with one big C curve, or kyphosis.

Look at yourself in a side view in a mirror while sitting and you’ll see.

And different types of seat and the position of your computer can also cause different types of C-shaped posture.

For example, if you are sitting looking downwards at your screen your head will tip forwards and you totally lose the neck curve, emphasising that C curve.

If you consider that the average adult’s head weights about ten pounds, that is a considerable strain when it is in a less than suitable position.

The more upright you are, looking straight at a screen, the less the strain on the neck will be over a long working session.

How you sit at a desk is also relevant.

A survey of office workers showed that a little over 50 per cent of people tend to sit in the middle of the chair, while 33 per cent sit back in the chair, and 15 per cent perch on the front of the chair.

Again, look in a mirror and see how those positions alter the sitting posture.

The old adage was that you had to have an upright position, with hips at ninety degrees to the spine, the shoulders back and the head as upright as possible.

That is not always easy if you are bobbing around with mobile phones in a cramped space.

That is why getting the desk, chair, computer and yourself into the best position is so important, and worth checking if you are getting pains.