WE ARE LED to believe that wearing glasses is a job for life, that once you have been diagnosed with a problem that requires you to wear corrective specs the best you can hope for is that it will not get any worse.

American writer Marilyn Roy thought so too until she abandoned her glasses and found that over the ensuing months, with a bit of effort, her eyesight improved. Then, being an enterprising American of course, she wrote a book adding profit to the saving she'd already made on her annual optician's bill.

Her book, Eyerobics, says that daily exercise can limber up those lazy eyes no matter how bad they are. The advantages are obvious. Queuing need no longer be boring when you can incorporate it into you daily eye near and far refocusing workout.

According to Roy, there is a high correlation between short-sightedness and doing a lot of close-up work. Our eyes are tired. Reliance on computers can cause eyestrain, focusing problems and blurred vision.

Roy is sceptical about opticians' motives, saying that nobody makes money telling people they don't need glasses. "Glasses mask the sight problem," she says. "Glasses mean the eye no longer needs to accommodate to the degree that it once did to focus clearly. Co-ordination and flexibility of the muscles of the eye may decline if the muscles are no longer required to work as hard."

John Davies, a 30-year-old publisher, agrees. "I lost my glasses and I didn't get round to getting a new pair. In the mean time my eyesight improved so that I didn't need them any more. I could read traffic signs from 25m again."

Miracle? Well maybe not. Another explanation is that John's youth means that currently his eyes can compensate for his minor vision problems but in later life, he will have to wear glasses again.

Gail Stephenson, head of orthoptics at the University of Liverpool, says "Declining flexibility of the eye muscles is a normal part of ageing. We use exercises to help people co-ordinate their vision and build up muscle strength. But short-sightedness and long-sightedness are caused by the front of the eye being either too curved or not curved enough, or being longer or shorter than normal. No amount of exercise will change that.

"What these exercises may do, at least, is refresh your eyes, avoiding headaches and easing tiredness. Vision can become blurred through fatigue and imbalanced use."

Marilyn Roy's Eye Exercises

There is a whole book of complicated tricks, but here are a few for starters.

1. Make sure your eyes get a balance between near and far vision during the day. Staring puts strains on the eyes.

2. Don't wear sunglasses all the time (unless you are trying to make it in Hollywood).

3. Treat eye training like any other exercise. As you train, and use glasses/contacts less, you will become stronger.

4. Massage brow and cheek bones around the eye to stimulate circulation.

5. Look out of a window frequently to relax the eyes. Roy says that by releasing tension, you free up the eyes to be more flexible.

6. Focus and defocus on optical illusions such as a stereogram (those patterns that have hidden three-dimensional pictures). This, says Roy, relaxes the tension that contributes to long and short-sightedness and astigmatism.

7. Sit with the television a little further away each day.

`Eyerobics' by Marilyn Roy is published by Thorson's, price pounds 7.99.