A study by the University of Mississippi found that Nintendo's Wii console has little effect on family fitness. PC World has all the details and says that while the console doesn't seem to have a big effect on the family as a whole, the somewhat confusing press release does seem to suggest that children did display a significant increase in aerobic fitness after three months of use.
Intriguingly, daily time spent with Wii Fit declined by 82 percent per household over the course of the study, from 22 minutes a day during the first six weeks to only four minutes a day during the latter six. The study's conclusion: "Modest amounts of daily Wii Fit use may have provided insufficient stimulus for fitness changes."
According to the press release, the study found that children "did display a significant increase in aerobic fitness after three months of use," which would seem to be a pretty significant positive development. Here's where things get confusing: The release goes on to conclude that three months of Wii Fit use "revealed no significant changes in daily physical activity, muscular fitness, flexibility, balance or body composition for the family as a whole."