It is only when the yearly IPPT test draws near that he starts hitting the gym twice a week.

But now, Mr Chee has found a fun way to stay in shape - through the Wii Fit released by Nintendo in Japan for its Wii console.

When Mr Chee and his wife get home from work, they spend an hour every night exercising with it.

The couple, who have been married for two years, ease themselves in with push-ups and crunches, before moving on to quicker and more strenuous exercises such as back lunges or a jog, finally cooling off with some yoga therapy - all these using the Wii Fit.

The Wii Fit is a game program that comes with a flat, rectangular board which works in tandem with a user's Wii. It is marketed at people hoping to lose weight and get fit in the comfort of their own home.

The Wii console has sold itself on its motion-sensitive controls, which mimic real-life actions such as swinging a tennis racquet, as well as its touted weight-loss capabilities.

In February last year, a study by Liverpool's John Moores University in England noted that long-term use of the Wii could help users lose up to 12kg per year.

However, short-term use would produce only a 'trivial' result.

But Mr Chee is in it for the long haul. He hopes to lose enough weight using the Wii Fit to drop a category from overweight to healthy on the Body Mass Index (BMI) scale.

This scale measures the general fitness and health of a person.

'There's a lot of motivation with the on-screen instructor and knowing you're making progress to new and more difficult exercises,' said Mr Chee.

One-hour workouts over each of the past 12 days have seen his BMI fall from 27.62 to 26.78, which leaves him hovering just outside of the 'healthy' BMI reading of between 20 and 25.

Mr Chee was willing to pay the higher price of $189 retailers are asking for the Wii Fit because 'it looked interesting and...we were keen to get fit'.

While the Wii Fit retails in Japan for around 8,500 yen (S$115), importers in Singapore have had to raise prices due to the difficulty in obtaining sets.

The high demand is partially fuelled by uncertain supply.

Mr Chris Sng, the director of supplier Funz Centre, said: 'We may not even see the US set released here, considering the shortages of other similarly popular games in the US such as Rock Band.'

Singaporeans cannot, however, play on the Japanese Wii Fit without a Japanese Wii, which means most have to wait till its United States release. That version is scheduled to be released before the middle of the year and will come at an expected price of US$69.99 (S$100).

So what is the Wii Fit's secret? Its two weight-sensors in the floorboard. The sensors extrapolate the weight placed on it onto a user's chosen exercise.

Mr Chee stands on the board and eases into a yoga position reflected on the TV screen. The system reflects his centre of balance by a small dot within a circle on-screen, which shifts as his balance changes.

Other users are more attracted to its casual fitness programme which encourages regular exercise.

Mr Lee Jin Lei, a 30-year-old freelance copy-editor, said he 'wasn't the type to be motivated to exercise'.

Yet he has used the Wii Fit for up to an hour each day since he bought it in mid-December.

Mr Lee said the Wii Fit was much cheaper than buying exercise machines individually, a sentiment Mr Chee echoed. 'My friends said exercise machines quickly become white elephants.'

A treadmill costs from just over S$1,000 to about S$2,500, while step machines go for between S$199 and about S$1,500 each.

Most retailers who imported the Japanese Wii Fit here said they sold all their stock within days, some even before making it to the shelf.

Marketing manager for Seow Choon Games, Miss Nicole Lim, 22, attributed its easy use as a key selling point. The store has a demonstration unit for people to try out.

Some gamers, though, are not attracted by the Wii Fit's supposed slimming powers.

Graphics designer Chen Gui Min, 26, who owns Wii Fits in Japanese and Singapore versions, said: 'I'd rather go out and exercise.

'I don't want to rely on a TV to do so. But if more titles come out utilising it, why not?'

neugene@sph.com.sg