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It is a common enough sight and one that can send parents shrill with despair. Their fit and healthy teenage offspring idling away the best years of their lives inert in front of the television screen.
But according to new research, watching a lot of television and playing computer games does not automatically make your child a couch potato.
An analysis of the activity diaries of 1500 12-16-year-olds by Loughborough University in Britain found the number of hours that youngsters spent in front of the box or on the internet was a poor indicator of their overall levels of activity.
There was also little evidence to suggest a major link between screen-based entertainment and obesity, according to the study's leader Professor Stuart Biddle.
"The idea that a child sitting there watching television like a couch potato is a problem is far too simplistic. There is no strong linkage between how much TV you watch and how much time you play competitive sports. There is room for both," he said.
Unveiling his research at the British Psychological Association conference in York, Professor Biddle said it was important to consider when your child was watching. For example, viewing between 9pm and 10pm posed little threat to their overall health because this was a time when they would normally be relaxing, he said.
But parents should be aware of the crucial period between 3.30pm and 6.30pm - after school and before the evening meal - when children exercised most.
"If they are not active during these hours it is very unlikely that they are going to be active at all," said Professor Biddle.
Childhood obesity rates have soared in recent years prompting fears of a generation blighted by diabetes and heart disease. However, the search for easy answers to these difficult problems was not always useful, warned Professor Biddle.
He said there was evidence that the number of hours children spent in front of the tube in the developed world was actually declining. In the UK, the average child watched two and a half hours of television a day, rising to three hours at the weekend. However, a study in the United States found that this figure can nearly double when computer use is added.
According to the research from Loughborough's School of Sport and Exercise Science - which didn't look at diet - one of the biggest causes of young people's sedentary lifestyles was the growth in the amount of time they spent in the car. The average child now spent an average of 40 minutes a day on automated transport, he said. This had been accompanied by a dramatic decline in walking or cycling to school.
One of the reasons for this was that children were now travelling further each day as a result of changes in education policy, he said. The average length of time spent commuting to school had doubled in the last 20 years. The loss of this active time had a serious effect on children's overall lifestyle. "If kids are not walking to school it may not seem a lot but it adds up to a great deal," said Professor Biddle.
The UK Government recommends that each child should take part in 60 minutes of moderate to vigorous exercise each day. A 15-minute walk to school would account for half the recommended daily activity. Professor Biddle said this type of exercise was more important to overall good health than the compulsory two hours of timetabled exercise they do each week at school.
"Parents are crucial in this. They have to ask themselves, are they encouraging their child to go in the car? Can they get their children to reduce their screen-based behaviour during daytime?" he said.
- INDEPENDENT
