Exercise alone fails to tackle childhood obesity, says study

Children at an obesity center.  The belief that obesity can be thwarted by getting tubby kids to exercise more is misplaced, says a study among nursery-school children.(AFP/File/Jean-Charles Sexe)

PARIS (AFP) - The belief that obesity can be thwarted by getting tubby kids to exercise more is misplaced, says a study among nursery-school children. In an unusual experiment, British researchers tested the exercise theory among 545 preschoolers among 36 nurseries in the Scottish city of Glasgow, where fatty diets and a couch potato lifestyle are entrenched.

With the consent of the children's parents and help of nursery-school staff, the researchers had half of the children do three 30-minute sessions of physical activity each week, while the other half followed their normal kindergarten routine.

Parents in the "exercise" group were also given an information pack about encouraging physical play and reducing the time a child spent watching TV. The leaflets did not mention changes to diet.

After six months, and again after a year, the doctors checked the children to measure their body mass index (BMI) -- a height-to-weight ratio that is a good indicator of fat.

They found that the children in the exercise group were nimbler, but their BMI was virtually unchanged compared with counterparts in the "control" group.

The study, which is published online Friday by the British Medical Journal (BMJ), is lead-authored by John Reilly, a professor of pediatric energy metabolism at the University of Glasgow.

The outcome demonstrates that there is no magic bullet to childhood obesity, the paper says. To tackle the problem will probably require a campaign on several fronts, especially on tackling diet, and which will require help at school and home and elsewhere.

According to the World Health Organisation (WHO), more than a billion people -- nearly one in six of the world's population -- are overweight, outnumbering the 800 million who are under-nourished. Within the European Union (EU), five million children are now obese.

The trend is widely attributed to high-calorie junk food, persistent snacking and a sedentary lifestyle. Other factors, such as genetic vulnerability to gaining weight or losing control over one's appetite, are also suspected culprits.