A study on Grade 7 students in Montreal finds that teens are spending a disturbing amount of time in front of computers, televisions, and video games.

Most kids (60 per cent) averaged 20 hours per week - or about three hours a day - either surfing the Web, watching their favourite shows, or playing games. Around a third clocked in at 30 hours per week and seven per cent racked up an astonishing 50 hours or more each week.

"This is a wake-up call for families, teens and parents to start to pay attention to this," says Mark Tremblay of the CHEO Research Institute (Children's Hospital of Eastern Ontario), who was not involved in the study.

"The Canadian Pediatric Society recommends kids spend no more than two hours a day watching television and clearly, a large majority of our kids are exceeding that," he told Canada AM.

The study also drew a link between socioeconomic status and screen time. Teens from poorer neighbourhoods were more likely to park themselves in front of TV and computer screens for longer periods of time, reports the study's lead author Tracie A. Barnett, an assistant professor at the Universit� de Montr�al's Department of Social and Preventive Medicine.

"Boys whose parents had lower educations were much more likely report more than 20 hours of weekly screen time," said Dr. Barnett.

The boys who lived in census districts with low education levels reported a two to tree-fold increased screen time. As well, girls from poorer neighbourhoods recorded higher screen-time compared to girls from richer postal codes.

Barnett and her team analyzed 1,293 Grade 7 students from 10 high schools in Montreal. Participants completed in-class questionnaires four times a year for five years and reported their usual hours of watching television, videos, surfing the Internet or using computers.

The researchers then defined neighbourhoods by census district, looking at average education and income levels within districts.

Overall, their study showed:

  • 52 per cent of boys and 26 per cent of girls reported average total screen-time levels above 42 hours per week;
  •  When it came to just TV or video use, 52 per cent of boys and 39 per cent of girls reported average use levels above 23 hours per week;
  • When it came to computer and Internet use, 24 per cent of boys and 7 per cent of girls reported average levels of almost 30 hours per week of use.

Television accounted for most of the screen-time, with 85 per cent of the pre-teens reporting less than 10 hours per week of computer/Internet use.

The amount of "screen time" stayed about the same as the kids entered high school, but television viewing generally decreased while computer use increased.

The study is being presented at the American Heart Association's 48th Annual Conference on Cardiovascular Disease Epidemiology and Prevention in Colorado Springs.

Tremblay says the health implications of the findings should be obvious.

"If an excessive amount of time is being spent sitting in front of the screen, that is time that is being displaced from doing other things that may be more constructive, such as homework, or physical activity of some nature, or chores around the house."

The Canadian Pediatric Society recommends that children's media use be balanced with sports, hobbies, creative play and playing outdoors. They also suggest that TVs, television, Internet-connected computers and gaming equipment be kept out of children's bedrooms.