Their arms are raised to the skies as they chant the song of the South Seas in unison, their hips moving rhythmically to a tune whose heritage is instantly recognisable. Hula dancing is taking off in Japan - and not just among women. An estimated 400,000 Japanese have caught the hula bug and are practising their wiggles and slower, more graceful arm movements. Perhaps surprisingly, a good number of them are men who say moving to the hula beat is an excellent way to free the mind of the stresses of the working week. Hula dancing has been growing in popularity in Japan for a decade or so, but that growth has accelerated in recent months. Demonstrations are held in shopping malls, specialist clothing shops have opened and music stores have large hula tune selections. But the biggest catalyst is probably the hit movie Hula Girls, which will represent Japan as the official entry for the Best Foreign Language Film at the Oscars in January. In a plot that has parallels with The Full Monty, officials of a fading industrial town in northern Japan decide to set up a Hawaiian village as a tourist attraction. A comedy tale that is based on a true story from the 1960s, Hula Girls opened late last month and plenty of Japanese men suddenly have an interest in becoming the hula instructor who woos the local girls one by one. To the twang of the ukelele, the Nagisa Boys practise twice a month and have performed at public events, including book signings. The 10-strong group range in age from 38 to mid-50s and are from a wide range of jobs. They include a computer programmer, a transport worker and an advertising executive. The one thing these men - who are also of the generation who saw Elvis Presley shimmy and shake in his series of Hawaii films - have in common is their love for Hawaiian dance. 'I didn't feel completely comfortable with ballroom dancing, but with hula - as long as you have musical accompaniment - you can even dance barefoot,' said Junichi Miyagawa. The 45-year-old leader of the Nagisa Boys told Aera magazine that hula 'is a great way to relieve the daily build-up of stress' and that the wiggling also helped promote the energy he needed to get through the working day. And the men who have taken to hula are also defensive of a hobby that is more commonly associated with women, pointing out that in the distant past, only men were allowed to dance the hula in Hawaii. For these middle-aged Japanese men, it's all about the power inherent in the ancient form of the dance. And they definitely don't wear grass skirts and half coconut shells on their chests.