'I WISH I had a chest like that,' says Steve, an academic in his early thirties. We are looking at a poster advertising Antaeus, a scent for men, made by Chanel. The poster depicts two things - a bottle of scent, and a male torso which has been worked so hard that it's made up of 14 separate, hairless panels, as if it's been tiled like a roof. You can see the man's neck, stretching off the top of the picture, and part of the head, but no facial features - no expression. This is not a person. It's a body. The message, or part of the message, is: improve yourself] Work on it] Here is a male body being used just like a female body - as an idea of perfection, as a generator of insecurity. 'Makes me feel guilty,' says Steve, only half joking, 'I should be working harder.' Steve works out, several hours a week, straddling the various body-building contraptions in his local gym, repeating the same exercises over and over again. He wants to look different.

Steve wants to look like some of the men - the bodies - he's been seeing recently on posters and television and movie screens. He wants the high muscle definition of the growing number of men who are photographed with their shirts off, who are employed, mostly, as hunks of beef - male strippers the Chippendales, pop star Marky Mark who is the Calvin Klein underpants model, screen stars like Brad Pitt and Steven Weber. There's now a huge pack of them, boys with the bodies of prizefighters and the career-structures of female starlets - they rise without trace, they're subjected to endless physical scrutiny, and no-one seems to care much what they think. Steven Weber, who played the boyfriend in Single White Female, said of his part: 'I have the traditional female role.' He walks around near-naked, often in bedrooms, has sex, and is brutally killed.

Men want to look more like men, but they're being made to feel more and more as women have been made to feel about their bodies. It's a mark of male insecurity that an objective standard of men's beauty is beginning to emerge, the very thing that angered feminists so much on behalf of women. But men appear to be accepting it. Why?

Sport and fitness have never been more fashionable. 'It's crossed all class barriers in the last decade,' says Michael VerMeulen, editor of GQ. Around 500,000 men now work out regularly in Britain's 50,000 gyms, and bodybuilding is one of the country's fastest growing sports. More men are having cosmetic surgery on their bodies than ever before - five years ago, 10 per cent of the clients at the London Hospital of Aesthetic Plastic Surgery were male; now the figure is 40 per cent. British men are beginning to have silicone implants in their chests - pectoral implants. In California, the spiritual home of bodybuilding, having a pectoral implant operation is known as 'having an Arnie', after the famous actor and bodybuilder. In Britain, it was reported last week, hundreds of women are turning to a support group called the Anabolic Steroid Wives' Association, because their partners, obsessed with physical training, have taken so many steroids that they have developed 'roid rage' - flying into uncontrollable tempers.

What is making men feel so vulnerable? Could it be a result of women becoming more independent, more powerful? Are the advertisers - who depend on insecurity - simply trying to expand their market, now that some women may be more self-confident? The beefed-up torso is currently selling all kinds of male accessories and other products: Seiko watches, Yves Saint Laurent creations, Givenchy and Chanel scent, Haagen-Dazs ice- cream, Calvin Klein underpants, Energie and Levi's jeans, among other things. The current ad for Levi's 501s is a masterpiece of instigation of male insecurity - a beautiful woman, a kind of Cinderella in reverse, searches for her ideal man by making men try on a particular pair of Levi's 501s. She keeps rejecting men for being too fat, until she finds the right man: a greasy mechanic with a triangular, sinewy, panelled torso. Message: social status doesn't matter; the important thing is the shape of your body. And the essence is to work hard - you couldn't look like that without months of toil in the gym.

Working out is masochistic; the first thing the customer learns in the gym is to see his body as an object. He doesn't sit there, strapped into his hydraulic machine, and listen to it when it tells him to stop - no, he crunches through the pain regardless. 'Women are choosier these days,' says Euan, a computer programmer from Brighton, who wants a bigger chest and better muscle-definition on his stomach. 'They're suddenly allowed to look at all this beefcake. And we're not allowed to do the same with them. They're getting their own back, I suppose.'

Euan is talking about For Women, Playgirl, Ludus and the other female soft-porn magazines which have entered the market this year, with their full-frontal spreads of naked men. 'So,' says Euan, 'I just train harder, go through more pain. If I don't, I can feel myself getting fat. I can feel the muscle-definition going.'

Men's nervousness of the pressure to look good has been called the 'Chippendale Syndrome'. 'I feel a new self-consciousness about my body that comes directly from the increasing public display of images of naked or semi-naked men,' confessed journalist Peter Baker in the men's magazine Achilles Heel. 'If I compare my body with how I think I'm supposed to look then I definitely have some more work to do.' When I asked 10 women what they thought of the New Torso, remarks varied from vague approval to: 'It makes me physically sick.' One woman said she didn't like muscular torsos per se, but liked the fact that they put men in their place.

Bodybuilding has always been a pastime for the insecure. In the Thirties, Charles Atlas advertised his 'Dynamic Tension' course with the words: 'I was once a skinny, timid weakling of only seven stone. I didn't know what real health or strength was. I was afraid to fight, ashamed to be seen in a bathing suit.' More recently, the Californian sociologist Alan Klein found, in a study of bodybuilders, that most had had childhood problems; they'd been stammerers, overweight or dyslexic. Bodybuilding, says Klein, is 'therapeutic narcissism.'

These days the therapy starts from the moment the male weakling walks into the bodybuilding section of the sports shop, where he is surrounded with a strong, forcefully-marketed sense of the thing he thinks he lacks, maleness; even the food supplements on sale are packaged to bolster the male identity. There they are, big squat white tubs which look like engine-oil containers, with bold dark lettering: 'Gainers Fuel 1000', 'Power Fuel', 'Diet Fuel', and 'MCT Fuel - Human machine oil' containing 'emulsified medium-chain triglycerides'. This is a world of quiet male suffering, a place where big men pick big fat tubs off the shelf and read slowly through the lab-reports, silently nodding, and then go home with a copy of Flex ('If I'm after more quadriceps separation, for example, I'll perform a few full, slow reps on leg extensions, then spend a minute or more doing burns'); or Bodypower (So stick to the fight when you're hardest hit/It's when things seem worse, that you must not quit'); or Arnold ('How to get really, really BIG]').

But will it make them happy, getting big like this? Marky Mark has been having second thoughts recently. His publicist says: 'He's less inclined to take his shirt off now in photo-shoots and shows, because he doesn't just want to be known for having a great body.' Raquel Welch could have told him that. Or Brigitte Bardot. Even Samantha Fox.

(Photograph omitted)