The government's health messages have never been clearer or louder: take responsibility, eat better, exercise more. Most of us find the exercise part a challenge, so we join a gym, go to classes or, increasingly, engage a personal trainer. According to the latest marketing-industry figures, 18% of us claim to use a gym regularly, and we spend £1bn a year on fees, home equipment, clothing and other paraphernalia.
But although people are happy to part with all this money, few stop to think about how well qualified and competent the gym instructors or trainers might be. Over the past year, it has become clear to me that not everyone gets value for money - or the health benefits striven so hard for.
Eighteen months ago, I decided, in a mid-life career shift, to become a personal trainer. I had no idea where to start, so I phoned up Sport England, the former English Sports Council, and asked. I was told there was no single qualification but had a couple of training providers recommended. I opted for one of the more expensive courses, which also turned out to be among the most reputable in the business, run by the training arm of the YMCA.
Since embarking on my training, I have found myself at regular intervals open-mouthed at some revelation or other. The first came even before I began, when a course administrator explained, to my incredulity, the structure of my training schedule. After the first 13 days' tuition, she said, I would take a written exam and practical assessment, after which I would be a qualified gym instructor. Thereafter it was a matter of layering up my skills and knowledge through the remaining series of courses.
This 13-day, 120-hour training base is an informal industry standard. It was described by one of my tutors - a highly qualified, very experienced and talented trainer - as "scary". Which illustrates perfectly my first experience of setting a real gym programme shortly after I gained that first qualification. I lay awake all night fretting about whether my advice might cause the premature death of my thirtysomething, overweight client from heart failure.
But there were more revelations through the year: the dubious value of "fat-burning" programmes on cardio machines, the pointlessness of most abdominal exercises, the highly contested pros and cons of stretching - not to mention the precision required for correct stretch technique, the potential for injury from certain common weights exercises and, perhaps most depressingly of all, the futility of diligently following the same exercise routine week in, week out. It is a basic exercise principle that you must challenge the body in new, different and harder ways in order to develop fitness. Why did no one at any of the seven gyms of which I have been a member in the past 15 years tell me that?
Now - but not 10 months ago - I am beginning to appreciate just how intensely customised a good instructor's approach needs to be towards each individual in their care. Jeremy Morgan, a personal trainer based at Westminster's Club at London's County Hall, has six years' experience and a clutch of advanced qualifications. He says: "It's not until you learn something deeper that you realise how very, very basic the initial training is. Ninety per cent of the people who come to see me have some sort of a problem: injury, age-related, health - all stuff that's not covered in a basic course."
In an industry lacking any agreed syllabus, formal standards or regulatory authority, there are hundreds of courses on offer. At one end of the scale, more than 5,000 sports science students graduate annually from university. At the other end are correspondence courses such as the fitness instructor certificate offered by International Correspondence Schools (ICS). No experience or educational attainment is necessary. Once you have done the written work you pay a further fee to attend a three-day practical assessment session run by the World Amateur Body Builders' Association and, hey presto, you are qualified. Worst of all, anyone can set up as a personal trainer or gym instructor, perfectly legally, without any qualifications at all.
However, that is about to change. In January the industry opened an official register of exercise professionals (Reps), with the aim of signing up all 25,000-plus instructors, coaches and trainers in the country. Only people who are appropriately qualified and insured will be accepted on to one of the register's three grades, and to remain on it, instructors must undertake regular professional development.
The register has government backing - an indirect consequence of the national obesity epidemic. The most effective alternative to expensive medical treatment for obesity and lifestyle-related diseases is exercise. GP referral schemes - exercise on prescription - are taking off, but the Department of Health will not allow GPs to refer stroke patients to 17-year-old gym instructors with three weeks of training. Cliff Collins, the Reps registrar, says the register will change the way the industry is run: "You can't get on to the register without a qualification. This is a pretty radical departure for the industry. It's a coming of age for us."
The idea for the register came from Andrée Deane, chairman of the Fitness Industry Association, who has been campaigning for it for seven years. This time, she says, the industry is taking it seriously: "All the main training providers are behind it, and the employers are hugely supportive."
They need to be: this is a voluntary initiative, but the stakes are high because of the involvement of the Department of Health. Statutory regulation with imposed standards is always an alternative.
Most of the big gym chains, from David Lloyd to DC Leisure, have agreed to sign up staff en masse, ensuring along the way that training levels are brought in line with the register's requirements. Four months after opening it, Collins has 13,000 names waiting to go on.
But, as Collins accepts, that is the easy part. Most gyms are single-site, local independents, where it may be harder to persuade staff and employers to fall into line. In its struggle for greater professionalism and status, the fitness industry will have to get to grips with another awkward reality: low pay keeps it locked in a cycle of poor- quality recruitment and poor levels of retention. Sarah Plant, assistant group fitness manager with DC Leisure, says: "People will leave our company to go and pack boxes for £8 an hour." Members may be paying gym fees of £500-plus a year but the instructors are only paid between £10,000 and £15,000 to help them get fit.
Deane senses movement here, too: "The bigger chains have sussed out that they need instructors at a certain level, and need to invest in them. As soon as we sort out the upper tiers of the register, it will have a knock-on effect on the people lower down."
Change will come, but probably because people who use gyms want it. We all need to stop thinking of the gym as just a hi-tech playground, and start treating it as another piece in the jigsaw of investments we make in our long-term personal security and wellbeing - and make our investment decisions with care.
· To check whether your gym instructor or trainer is on the register, call 0845 601 6067. Bear in mind, though, that registration is at an early stage.