Of more than 1,200 Canadian high schoolers researchers surveyed, one-quarter said they played "exergames." And on average, that translated to almost an hour of exercise on two days out of the week.

That, researchers say, gets kids part-way to the exercise dose experts recommend: an hour of moderate to vigorous activity on most days of the week.

Active video games - like Nintendo's Wii Fit, Dance Dance Revolution, and Sony EyeToy exergames - get kids off the couch and dancing, boxing, doing yoga and playing sports in their living rooms.

Some small studies have found that they can help kids burn calories and possibly shed a little weight.

But it hasn't been clear how often kids use the games in the "real world."

Erin K. O'Loughlin, the lead researcher on the new study, said she was surprised that so many kids use the games.

"And they're exercising at levels that may help them meet guidelines," said O'Loughlin, of the University of Montreal in Quebec, Canada.

"I would never say this should replace regular physical activity," O'Loughlin added. "Kids should still be going outside and playing and getting exercise."

But the reality is that many are not, she said. So if exergames help some kids get off the couch and sweat, that's better than being completely sedentary.

And, O'Loughlin said, the games may help some kids gain confidence in their sports skills - possibly enough that they'll want to start playing sports the old-fashioned way.

MORE LIKELY STRESSED ABOUT WEIGHT

The findings, reported in the journal Pediatrics, are based on a survey of 1,241 Montreal high school students. The kids answered questions on their weight and lifestyle habits, including exergaming.

Overall, girls were more likely to play exergames: 29 percent did, versus 16 percent of boys.

Exergamers were also more likely than other kids to be stressed about their weight, or to spend more than two hours a day watching TV.

O'Loughlin said the games may be especially appealing to some kids who are insecure about their weight and exercise abilities - especially girls.

Video games cost money, of course, and that could be a barrier, O'Loughlin said.

The games themselves run $15 to $20 or more. And the console systems generally range between $100 and $300.

But, O'Loughlin noted, surveys show that most U.S. kids already have video game systems at home. And if parents buy active games instead of traditional sedentary ones, the costs could be minimal.

"If you notice that your kid is spending a lot of time in front of the screen, this might be something you'd want to try," O'Loughlin said.

In general, experts recommend that kids get no more than two hours of "screen time" - TV and computers - each day. So active games would ideally need to replace, not add to, kids' screen time.

In the past, one criticism of active video games has been that kids could advance through them without ever getting on their feet. But newer motion-tracking technology has changed that, O'Loughlin noted.

"You have to actually move to win the game," she said.

The study was funded by the Canadian Cancer Society and the National Institute of Public Health of Quebec. None of the researchers reports any financial interests in the work.

SOURCE: bit.ly/U1lyw0 Pediatrics, online October 1, 2012.

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