YOU wouldn't expect to find a videogame in the middle of an exercise convention – but at the Australian Fitness Expo, the place was teeming with technology.

There were virtual fighting machines, running games, and even an exercise bike that simulated the Tour De France. But the biggest stand was reserved for the most unlikely demonstrator – Nintendo.

The computer game company muscled in on the expo to exhibit its upcoming new game, Wii Fit. It consists of a series of minigames controlled by a player standing on a "balance board".

"The Wii balance board is almost like a set of scales - it weighs you, you input your height and you can do your BMI (Body Mass Index)," said Nintendo spokeswoman Heather Murphy.

The Japanese model of the balance board, on display at the Fitness Expo, can take a maximum body weight of 136kg. The Australian model, due for release next month, can take up to 150kg.

"There's a whole range of exercises and different activities that you can do," Ms Murphy said.

Players keep their feet (or hands) anchored on the board and move their bodies to mimic particular activities, such as defending a soccer goal, walking a tightrope, or dancing with hula hoops.

More serious exercises include muscle workouts, aerobics, and yoga.

"Yoga will show you your centre of gravity and also it will guide you through the breathing," Ms Murphy said.