You might think that Wii Fit was a reaction to the popularity of games like Wii Sports and Wii Play, but according to Wii Fit lead Takao Sawano, the health-centric game "existed in the center of Miyamoto's brain before the console was released". Sawano gave GDC attendees a rare look into the Nintendo design philosophy today, showcasing the initial design documents for the Wii's best-selling titles, as well as giving us a visual walkthrough of the development of the Wii Balance Board.

Shigeru Miyamoto's notes on what was then known as "the Health Pack" didn't provide much in the way of direction to those on the hardware and software development side at Nintendo. He simply passed on to the team how much he enjoyed weighing himself everyday and monitoring his weight. "This is bound to lead to something interesting", Miyamoto said to what would become the Wii Fit team.