One in every three children surveyed in the south east is either overweight or obese, according to a report published yesterday.
The report, based on a pilot project carried out by the South Eastern Health Board and the Centre for Health Behaviour Research at Waterford Institute of Technology, also found that boys spend more time watching TV than girls.
The four-month pilot project, centring on 12 schools in counties Carlow and Kilkenny, also found that more than half of all 10-year-olds have a television in their bedrooms, a factor which contributes significantly to obesity.
Of the 300-plus children surveyed, one in every three was either overweight or obese (26 per cent overweight and 8 per cent obese) when classified using International Obesity Task Force cut offs.
Three quarters of the children travelled to school by car while over half rarely engaged in any "vigorous" energy-burning activity during lunch breaks.
Most children also believed they would be "left out" of conversations with their friends if they reduced their television watching, with boys reporting higher levels of screen-time viewing than girls.
Run in conjunction with teachers at the participating schools, the "Switch Off, Get Active" pilot project is the first major study to be carried out in Ireland into the impact of TV viewing and computer games on children's lifestyles.
The project involved the introduction of teacher-led "sedentary intervention" programmes at the schools. These involved pupils keeping a daily diary of their television viewing while a reward system was operated, with points awarded for activity and deducted for inactivity.
After four months, the 312 children involved in the project cut down on their television viewing time and increased their levels of physical activity. The children were also more aware of the importance of physical activity.
According to Mr Michael Harrison, lecturer in exercise science at WIT, the project has yielded a rich source of data on the behaviour of 10-year-olds.
"The TV viewing habits in a proportion of the children and their access to screen technology is a cause for concern. So too are the levels of overweight (children) found in this study.
"We have also shown that a school based teacher-led intervention can be effective in reducing screen viewing and increasing physical activity."
Mr Séamus Moore, assistant regional manager with the South Eastern Health Board, said the project could now be assessed in terms of its introduction to other schools. "The findings give us a lot of valuable information to work with and now that the project has been evaluated it can be rolled out to other schools in the SEHB area.
"Future research will need to address the sustainability of this schools' based intervention and identify the frequency and type of follow-up that is needed to maintain attitudinal and behaviour change," he emphasised.