More 'Screen Time' Linked to Poor Fitness in Girls

Jan. 8 -- WEDNESDAY, Jan. 7 (HealthDay News) -- Teenage girls who spend more than two hours of "screen time" a day watching TV, surfing the Web or text-messaging are less likely to be physically fit, a new Australian study finds.

Interestingly, boys who were part of the same study were more likely to be able to "sit and be fit," said lead author Louise Hardy, a postdoctoral fellow at the New South Wales Centre for Overweight and Obesity at the University of Sydney.

Boys, particularly older teenage boys, may be less affected by the time they spend watching TV, playing computer games, and other small-screen activities because their growth spurts have led to sufficient muscle mass to maintain fitness and still engage in a large amount of sedentary behavior, the study suggested.

Boys are also more likely to play sports as well as computer games, said Dr. Goutham Rao, clinical director of the Weight Management and Wellness Center at the Children's Hospital of Pittsburgh. An adolescent boy who's on the swim team, for instance, may also spend a lot of time playing a video game like "World of Warcraft," he said.

"There is a culture of physical fitness among boys, and there also is a culture of sedentary activity," he added.

From his experience, Rao said, "there is only a small subset of teenage girls who engage in physical activity regularly." He added that he finds that adolescent girls at his center are more interested in small-screen communication devices, such as texting, than they are in video games.

The Australian researchers said their study may be the first to associate "sedentariness" -- a measure of cardio-respiratory fitness -- with the widely accepted American Academy of Pediatrics' guidelines that children from 2 to 18 years old not spend more than two hours a day on small-screen recreation.

"This is important because ensuring that one has good cardio-respiratory fitness reduces the risk of developing cardiovascular disease," Hardy said. For the study, the researchers measured cardio-respiratory fitness based on the number of laps run at a set pace.