The Official Nintendo Magazine commented on something interesting in their review of EA Sports Active. Despite being bundled with two peripherals to help you keep fit, an hours play burns only 180kcal. Or half a Mars Bar, if you prefer.
180kcal is around the same amount that playing any Wii game will burn off, and also less than going for walk, which takes 240kcal.
The magazine – which has an exclusive of Red Steel 2 this month – suggests that playing Guitar Hero or Rock Band would give you a better workout.