I've always thought that naming a product has to be the easiest job in the world, as the name often reflects the purpose which the product serves. Take the Clapper, which works by clapping, or a doorstop which just happens to stop a door. So taking these into consideration, what do you think the Wii Fit is supposed to do? If you guessed “make you fit,” you're wrong.
So where do I get off saying something like that? It's not because I read a study from a doctor that says it won't make you fit, but this actually comes from Miyamoto. Here's a few lovely quotes from the man behind the Fit (and the rest of Nintendo).
I don't think Wii Fit's purpose is to make you fit; what it's actually aiming to do is make you aware of your body. That's why we wanted people to talk with their families about Wii Fit, and become aware of these things together as a group. If you're standing still, and it tells you 'Your body is swaying', you can see on the training results screen that your body has been shaking. But I think you'd never realize that your body is shaking in day-to-day life. I think becoming aware of things like this about yourself is quite interesting.
While I never expected something like the Wii Fit to make me ripped, I did at least think Nintendo was trying to help people become fit. I guess the old standby of “That Little White Thing You Stand On” just wouldn't have had the same ring to it.