The signs were there from the beginning. I knew before I even stood on it that the thing would tell me that I was overweight. The clue was in three letters – BMI or Body Mass Index.

BMI is essentially a statistical measure of the weight of a person scaled according to height. The problem is that BMI was never intended to be a definitive measure for everyone but rather a simple means of classifying sedentary individuals of average body composition which means that for a lot of people, BMI is not a true reflection of their physical condition.

Take me for example, at around 6 foot tall and just over 200lbs my BMI is nudging 28 which puts me at the top end of the overweight category. But I don't think I'm overweight. I go to gym 4 times a week, push fairly heavy weights and have the outline of a sixpack (if I tense really hard and squint a bit).

The fact is that the medical establishment has generally acknowledged the shortcomings of BMI because it does not take into consideration factors such as frame size and an individual's fat to muscle ratio. So why did Nintendo choose to use BMI with Wii Fit? I think it's partly because a large proportion of Wii Fit users WILL BE sedentary individuals of average body composition. The other reason may have had something to do with the fact that, as far as I'm aware, there are no other internationally recognised weight-based categorisation systems, so a flawed system is better than no system at all. And to have tried to come up with their own classification system would have raised more issues that it would have solved.

So I don't have a problem with Wii Fit telling me that I'm overweight, but not everyone could feel the same way. For some, even if they suspected that they were overweight, being told by a cheery video game that you actually are overweight, or even obese, may go one of two ways. Our newly weight-challenged friend could finally receive the wakeup call they needed to kick start a positive change in lifestyle or they could simply throw Wii Fit out of the window together with its Wii Board from hell. I certainly hope it's the former response.