Real Life: Fitness is delivered to your door: You don't have to be Madonna to hire a personal trainer, reports Rosanna de Lisle

'PERSONAL trainer? An aerobics teacher who actually comes to your house?' said a friend. 'How hilarious.' In Britain, the personal trainer, if heard of at all, sounds like another faddish accessory for the bored, probably obese, almost certainly American, rich. An image of Madonna jogging in Hyde Park, surrounded by coach and henchmen, springs to mind.

According to the National Register of Personal Fitness Trainers, one-to-one training is catching on. Formed in January 1992, the register has 'just over 300' personal trainers on its books, and took '700 calls in the first year'. Vicky Hosking, national co-ordinator, checks trainers' credentials and then gives their telephone numbers to potential clients. Callers are asked what sort of trainer they want (eg male, female, tough, gentle) and given a couple of local names.

So who needs a personal trainer? Given that they charge between pounds 20 and pounds 50 a session - compared with about pounds 3 for an exercise class at a local authority sports centre - and recommend three sessions a week, personal training remains beyond the budget (to say nothing about inclination) of most of us. Ms Hosking admits that 'the dominant group are busy executives, people with jobs that involve travel, people who haven't got time to go to a gym or people who can't face going to a gym because of the image. They are

30-plus with quite good disposable income. And they all lack discipline.'

She sent two trainers to meet me for a trial session. First to visit was John Taylor, whom she described as 'my star pupil and ideal trainer'. John, 29, used to play international rugby and has kept the beefcake physique. Three years ago he became a personal trainer in London, having got bored of his job with Barclays Bank in the South-west. He charges 'about pounds 20 to pounds 25' an hour and is fully-booked. He asked about my 'exercise background' - I go to classes rather sporadically and play tennis in the summer - and then put me through the YMCA Three Minute Step Test for a more scientific assessment.

I rolled back the rug and John unpacked his 'step' - a rubber-topped glass fibre board with pink and green feet stacked to the great height of 12 in - and then got me to step on and off it to the time of a metronome. This was harder going than it sounds - and showed in the results. Whereas my resting heart rate and blood pressure had looked 'very good' before the test, just three minutes' exertion rendered me only 'averagely fit'. But John was very nice about it and told me there were people so unfit they couldn't take a fitness test at all.

Next, he got out a 'Body Slide' - a sheet of tough, slippery plastic, six or seven feet long - and put bright blue bath caps over my shoes. The idea was to shimmy across from side to side without collapsing into the splits. I had had visions of being put through a punishing regime by a sergeant-major type, but even the tests were fairly painless. John explained that, 'especially with lady clients', he did not do body fat measurements until he had 'earned their trust'.

My second trainer, Maria Del-Mar, 27, also spared me the callipers, but not out of kindness. London born and bred, she is petite and assertive, bouncing about in a black tracksuit. This morning I would be running and power-walking round the garden. As I jogged, Maria ran circles around me - 'I hope you don't mind me staring at you like this' - inspecting and instructing. 'Squeeze your bottom, really sque-e-eze it.'

Maria said: 'I think most of the population should have a personal trainer. It is expensive, but you would pay to go to a physiotherapist or a shrink. Only so many people can afford a personal trainer. But in the long term, the value for money is far greater than going to a health club.' I found this last claim rather hard to swallow: Maria costs pounds 35 a session, so if you take the advised three sessions a week, that is more than pounds 100.

Still, the clients rave. Susie Bell, a therapist in her fifties, started training with Maria last Christmas. 'I haven't got the motivation to go to a club. Maria is just right: she's quite pushy but enthusiastic and fun. She's not cheap but if she had been cheaper I think I would have been suspicious.'

'I tried classes and I hated them,' said one of John's clients. 'I'm very tall, I'm very conscious of my body and I hate making a fool of myself.' She has been seeing John 'twice a week for nearly a year. He's become a friend.'

The National Register suggests that you devise a programme and then 'work your diary around it, not vice versa'. Is exercise that important?

Maria looked incredulous. 'Of course it is'. But, she went on, 'I would never ask my client to work their diary around me. I'm dealing with high-powered business women. I do not come before work, husband, baby or problems.'

One-to-one trainers consider themselves more than mere fitness instructors. Like hairdressers, they get to know their clients intimately. 'They see more of me than their best mate,' said Maria.

'Rapport is very, very important,' explained John. 'You're almost a pseudo- analyst'.

They are wary of being hired for the wrong reasons - 'I know of some gay trainers who have been inundated by the wrong kind of calls,' said John - and demand geniune commitment from a client. (Maria, for instance, operates by contract).

'People have this image of sex objects coming to their houses,' says Ms Hosking. 'We are not a dating agency.'

I'm still not convinced that personal trainers are not mainly for the rich, vain and weak-willed (or agoraphobic). Even if the cost was not prohibitive, I do not think I would want that much attention. I am happier lost in a class of 40.

But perhaps that is because, as Susie Bell says, 'Anything that's personal seems luxurious. It's not very British to do something for yourself.'

National Register of Personal Fitness Trainers: (0992) 504336

(Photograph omitted)