By Megan Lane BBC News Online

Last year was a bumper year for fitness centres, and in 2002 yet more will open their doors. It's almost as if we believe that paying gym fees will miraculously make us fitter.January: Fitness centres look forward to the annual boom in membership sparked by post-indulgence guilt.

February: Countless wannabe fitness fanatics revert to their usual lazy routine while continuing to pay up to �80 a month for a gym membership they will rarely, if ever, use again.

Fat of the land

Up to a million Britons a year join a gym for the first time Mintel figures

The psychology is simple: you feel a bit fat and unfit so you join a gym in the belief that paying all that money will make your exercise regime doubly effective. You don't go very often, so you feel guilty (as well as fat and unfit). Yet to cancel the membership - thus saving hundreds of pounds a year - is to admit defeat, after which there's nothing for it but to accept life as an unfit bloater.

If this sounds familiar, you are not alone. A sizeable proportion of new members lose the will to sweat within weeks of joining up. Not even the thought of boosting the gym's coffers for free provides much incentive.

Classes may include Brazilian martial arts

Those behind the UK's burgeoning fitness empires can hardly be complaining.

To lure yet more of us in, new gyms are cropping up throughout the year, many with a growing emphasis on mind as well as body in the form of yoga classes, cyber caf�s, stress management courses and low-calorie menus.

The plush Holmes Place chain plans to open seven new health centres around the UK and Europe this year, and in late spring the chain launches its first assault on the American market with a branch in Chicago.

And Fitness First, which operates in more countries than any other firm, is set to open 10 new centres in the UK this year - nine in time for January's membership bonanza.

Let's get physical

The health and fitness market has grown from �682m in 1996 to an estimated �1.6bn in 2001.

Fit for life

Set small and achievable goals Don't regard a lapse as a failure Take the stairs, walk to the shop, do some housework

Yet a survey by market analyst Mintel found that one in five members use the gym less than once a month. Of those who do attend regularly, using the sunbed is one of the most popular incentives.

At the same time, a fifth of women and 17% of men are medically obese. Could these be the same people who drive miles to the gym only to top up their tan?

Others, too, seem to forget that exercise can be free - witness those who stand on escalators at all times, then pound away on a state-of-the-art Stairmaster three times a week.

Do you want abs of steel or saggy man-breasts?

This would appear to be a prime example of the money v calories theory, which holds that the more you spend, the more you expend.

Perhaps there is something in it. Think of the effort involved in getting a buff belly to rival that of Geri Halliwell or Wimbledon champion Goran Ivanisevic. Doing dozens of crunches under the watchful gaze of a personal trainer is just the half of it.

The first big test comes when you are asked to sign over the small fortune required to cover joining fees and a year's worth of monthly payments. Then there's the new trainers, the Lycra gym wear...

If that doesn't get your heart rate up, nothing will.