In case you hadn't noticed, fitness is big business. On a console known for its wide-ranging appeal, Wii Fit is the absolute king and ruler of casual gaming, having spent no less than 13 weeks at the top of the UK sales charts. Perhaps in future years social scientists will look upon this period as a watershed moment in our culture - the threshold of an era in which clinically obese people ceased to exist. Children will visit museums to look at waxwork effigies of their enormous ancestors. "Why were they so large, Mummy? Why? I'm scared."

Okay, so probably not. The fact remains that Wii Fit is an enormously successful product, and yet so far no-one had really made a serious bid to contest its lucrative territory. All this is about to change with the release of EA SPORTS Active - a product that promises to act as a virtual personal trainer. Like Wii Fit, Active is bundled with additional equipment - an elasticised cord and a leg strap designed to hold the Nunchuck - and rather sensibly, it will also offer optional support for its rival's Balance Board.

EA says that it has set out to take a fairly Westernised approach to exercise with SPORTS Active. Initially I assumed this meant that you'd pay £80 for it and then immediately put it in a dark cupboard under the stairs, but as it turns out this claim relates more to an emphasis on rigorous circuit-style exercising. The idea is that you pick a selection of tasks from the 30 on offer and chain them up to form a routine. While none of these activities could be described as Herculean, they seem more strenuous than those offered by Wii Fit: I had certainly worked up a mild sweat by the time I'd finished EA's practice routine. Then again, I gave up physical exercise round about the time that I bought a copy of Final Fantasy VII - so perhaps this was somewhat inevitable.

In the final product you'll be able to choose from a variety of pre-set routines focusing on upper body strength, lower body strength, cardio, or some combination of the three, or else you'll build your own circuit from scratch. You'll also be able to tinker with the difficulty settings for each activity, so if you want to alternate between hard exercises and light ones, that will be possible. As you're sorting out your selection you'll be given a total time for your planned workout, along with a total amount of calories you'll burn. The game keeps track of your efforts over time, and obviously the idea is to keep coming back every day until you're a finely-toned slice of übermensch pie. If you don't want to bother with setting up a programme for yourself you can also jump straight into something called The 30 Day Challenge, an option that provides you with a new set of exercises each day, with the aim of improving your overall fitness within a month; expect this to be a major selling point with casual gamers up and down the country.

You too can have buns like these...

Amid the chaos of last week's showcase event, there wasn't really time for a full-blown workout. Instead, members of the press were invited to take part in The EA Demo Workout: a mighty undertaking that burned off roughly 25 calories in the space of a few minutes; considering that I wolfed down about five chicken sandwiches at the buffet lunch, this probably didn't do much for my long-term fitness. Never mind - at least it gave me an opportunity to try out a few of the activities.

Like Wii Fit, Active sets out to hide its exercises behind a range of fronts that are designed to make the whole experience more enjoyable: a "dancing" mini-game is used to get the player to make simple arm movements either side of their body, while another activity cunningly masks a sort of squatting exercise by presenting it as rollerblading. Essentially, you just bend your knees and lean forward to make your on-screen avatar speed up. Every once in a while you'll come to a ramp that must be jumped, requiring you to hop up in the air; if you manage to jump while your character is at the peak of the slope, you'll pull off a flashy trick as a kind of mild reward. It's simple stuff, but enjoyable enough - particularly if you're playing alongside a friend. Activities can be played competitively, or you can opt to work towards a common goal together. In both cases there should be plenty of opportunity for fatuous gloating.

Both of the bundled accessories seem to do their job fairly well. The thigh-mounted holster for the Nunchuck is relatively comfortable and can be removed and put on fairly quickly - which is just as well, since you'll often have to switch back and forth between different setups as you move from one activity to the next. The obvious advantage of the strap is that it allows the Nunchuck to monitor your leg movements, which in turn opens the door to simple jogging and leg-pumping exercises. While you can get away with doing these things without feeling too silly, I'm not sure if the same can be said for EA's large rubber band. It basically resembles a large red elastic strap with handles at either end, and the idea is that you stand on the middle of it while pulling the sides upwards as if you're lifting weights. As an easy way of providing elastic resistance, it works fine - but it still feels a bit like you're wrestling with an enormous condom.

The bottom line, however, is that it seems as if EA SPORTS Active will be very successful at achieving its goals. While I doubt that many hardcore gym-goers will be lured away from their swanky memberships, there are a lot of people out there who want to keep in shape. EA knows how to make a good-looking product that appeals to the masses, so it's quite possible that this will take a hefty bite out of Wii Fit's market share. Meanwhile, we'll all sit on our arses and take another bite out of something deeply unhealthy. Five a day, you say? Vegetables are for losers, man!

EA SPORTS Active is due out for the Wii on June 22.