Active video games, like Nintendo's Wii, might not count for as much exercise as many parents hoped.

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he boxing motions and arm waving often associated with the Nintendo Wii have been a core part of the gaming company's marketing strategy ever since the console made its debut in 2006. The Centers for Disease Control and Prevention recommends that kids get an hour of exercise per day, and early research concluded that "active" video games, such as Wii Sports and Wii Fit, could help. But according to a new study published in the journal Pediatrics, that might have been wishful thinking. Here, a brief guide:

What's so special about "active" games?
The basic idea behind Nintendo's fitness initiative is to get gamers to move more when they play, and thus burn calories. This is accomplished through special motion controllers, dance pads, or a yoga-friendly balance board. Games like Wii Fit Plus and Dance Dance Revolution Hottest Party 3 require players to use their whole bodies to get in on the action, not just the thumbsticks they're accustomed to on other consoles.

And that's better for kids?
In theory. So researchers at Baylor College of Medicine in Houston put the games to the test. They gave Wii consoles to 78 kids between the ages of 9 and 12. Some of the kids were handed a set of "active" video games, and others were given a set of inactive titles, such as Mario Kart Wii and Madden NFL 2010. The kids kept a journal of their playing time, and were required to wear an accelerometer throughout the day to track how much they moved around. 

What happened?
Over the 12 weeks of the study, kids who played the active video games didn't get any more exercise than kids who stuck with traditional, inactive ones. "Frankly, we were shocked by the complete lack of difference," says study author Dr. Tom Baranowski. 

So what does that mean? That the Wii doesn't work?
It means that the children "either did not play the active games at the same level of intensity as in earlier lab experiments, or they chose to be less active at other times of the day to compensate for the increased activity," says Ryan Jaslow at CBS News. Studies like this are interesting, especially since Nintendo markets a number of its titles for their purported health benefits, says Thomas Whitefield at Nintendo Life. But let's remember: These games "are only as active as gamers make them." 

Sources: CBS News, Daily Mail, Nintendo Life, Reuters