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TV Watching Linked to Physical Inactivity, Study Finds
Researchers discover that computer use, video games and reading are less strongly connected to kids' inactivity
BY LORI BONA HUNT
A lack of physical activity is more strongly linked with TV watching than with other types of sedentary activities like computer use, video game playing and reading, according to recent research by Prof. John Dwyer, Family Relations and Applied Nutrition. The study also revealed that children who watch TV for more than six hours a week are much more likely to be physically inactive.
“This research confirms a universal suspicion: the more television kids watch, the less energy they expend on physical activity,”says Dwyer, a specialist in physical activity promotion. “But it also goes one step further by showing that TV viewing is more connected to physical inactivity than are other activities like playing video games, and by suggesting that watching TV reduces energy expenditure, increases food consumption and decreases resting metabolic rate.”
Published recently in the Journal of Adolescent Health, the study was conducted with Kenneth Allison, director of physical activity research at the University of Toronto. Other researchers in U of T's Department of Public Health Sciences also contributed. It was funded by the Heart and Stroke Foundation of Ontario.
The researchers tracked the weekly time youths spent on sedentary activities and measured physical inactivity through daily energy expenditures assessed through a questionnaire.
The study was based on a survey of 7,982 Canadian adolescents aged 12 to 19 participating in the Canadian Community Health Survey. The results were produced after controlling for sociodemographic variables, health status and body mass index.
In females, as little as six hours of television viewing per week led to a significant reduction in physical activity; in males, it was 20 hours or more.
Interestingly, the study found that computer use is not significantly related to physical inactivity. In fact, the researchers found that boys who spend about six hours a week on a computer are less likely to be inactive compared with non-computer users.
Allison notes, however, that the study didn't differentiate between the type of computer use (e.g., playing games and surfing the Internet versus doing homework). “Future research should include a more detailed assessment of computer usage to clarify the association between it and physical activity.”
The researchers admit that breaking the television watching habit might be difficult for many adolescents — and their parents. They say parents can help by providing a positive role model for their kids by limiting their own TV viewing time, by limiting the consumption of snack foods while watching TV, and by planning a viewing schedule and letting kids pick their favourite shows.