TOKYO - Glistening with sweat, Satoko Yamanouchi's biceps ripple and the veins in her neck throb as if about to pop as she strikes a fearsome pose at the Japan bodybuilding championships.

An hour later, the pint-sized Nagoya housewife is close to tears after narrowly failing to retain her title from a field of 34 bronzed and impressively buff ladies, most of them in their fifties.

"I was pathetic! A silver medal means nothing to me," said the sinewy ex-champ, who stands just 1.58 meters tall and weighs about 50 kilograms. "It just means you're the best loser."

A self-confessed gym rat, Yamanouchi is the poster girl for Japan's growing number of female bodybuilders, helping break down gender stereotypes in the country.

"I want to help change perceptions so that more people can appreciate the beauty of a muscular woman," said the five-time national champion after a punishing two-hour workout a week before the competition.

"When I tell people I'm a bodybuilder, it freaks them out," added Yamanouchi, who became hooked on the sport in her late forties after looking for a way to keep fit.

"I want to look beautiful and keep my femininity. I just don't feel like a regular housewife," said Yamanouchi. "I'm always striving to create the perfect body."

The number of bodybuilders registered with Japan's national federation has almost doubled over the past six years to around 3,000, with women making up 10 percent as part of a nationwide fitness boom, officials said.

In aging Japan, female bodybuilding is dominated by women in their forties and fifties, as many usually only start after their children have grown up.

'Bikini fitness'

As women's bodybuilding becoming a serious business, other bodybuilding sub-genres have sprung up in Japan, including "bikini fitness" - a category that has turned Yuri Yasui into a magazine cover girl.

A two-time Japan champion, the statuesque 33-year-old is another who caught the workout bug after initially wanting to lose weight.

"When I started training seriously, my parents were dead against it - even my friends were," said Yasui, a bank employee from Nagoya, a city southwest of Tokyo, who won her first national title less than a year after taking up the sport.

"They didn't want me up there in front of strangers in a bikini flashing my bottom.

"At long last women are starting to work out regularly, but Japanese men still don't really accept muscle-bound women," said Yasui after lifting weights at a Tokyo gym.

"It's important to change attitudes. The way to a feminine body - getting that tiny waist and a round bum - is by building muscle.

"Ever since I was at college, I adored Wonder Woman," added the 1.73 meter tall woman.

Agence France-presse