Cochrane Researchers have found that school-based physical activity have positive outcomes despite having little effect on children's weight or the amount of exercise they do outside of school.
They conducted a systematic review of studies on physical activity programs in schools and found that school-based programs increased the time children spent exercising and reduced the time spent watching television.
Programs also reduced blood cholesterol levels and improved fitness – as measured by lung capacity.
However, programs made little impact on weight, blood pressure or leisure time activities.
Exercise helps to maintain a healthy weight, yet studies show most children do not do enough exercise to give any health benefit.
The World Health Organisation has identified schools as important settings for promotion of physical activity among children.
For the study, the researchers reviewed data from 26 studies of physical activity promotion programs in schools in Australia, South America, Europe and North America.
Most studies tried to encourage children to exercise by explaining the health benefits and changing the school curriculum to include more physical activity for children during school hours.
Programs included teacher training, educational materials and providing access to fitness equipment.
"Given that there are at least some beneficial effects, we would recommend that schools continue their health promotion programs. These activities should also be supported by public health unit staff, and parents and teachers as positive role models," said lead researcher, Maureen Dobbins, who works at the School of Nursing at McMaster University in Ontario, Canada.