Sales of Nintendo Co.'s "Wii Fit" game exceeded 3 million units in Japan since its debut in December 2007, becoming the second game for the Wii console to surpass that milestone, Enterbrain Inc. said Wednesday.

Cumulative domestic sales of the game reached 3.04 million units from Dec. 1, 2007, to Jan. 4, the Tokyo-based video-game researcher said. The "Wii Sports" software released in Japan at the same time as the console in December 2006 has already sold more than 3 million copies, according to the statement.

The "Wii Fit" program includes a balance board that allows users to simulate activities such as jogging and skiing.

Kyoto-based Nintendo has sold 7.67 million Wiis in Japan, Enterbrain said.