Shigeru Miyamoto has said that Wii Fit isn't really meant to make you fit (like the title suggests). It won't give you a six pack or help you finish the London marathon. He says it's only going to make you more aware of your body. And that's a good thing.
Speaking to Nintendo boss Satoru Iwata about the ideas surrounding the creation of Wii Fit, Miyamoto said, "I think it's important to make discoveries like this about yourself. I forgot to mention something important earlier: 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."
Read the full interview here. We didn't want a six pack anyway...