A DOCTOR is calling on schools to devote more time to sports studies and less to academic subjects.

Leading Bolton GP Dr Ian James says it would be a perfect way to battle rising levels of obesity among children.

Dr James, from the Spring House Surgery in Chorley Old Road, spoke out following a new study which said exercise not healthy eating is the key to beating childhood obesity.

The study, which has been published in the online health journal PLoS Medicine, surveyed 5,550 British children and found lack of exercise is a key factor in the development in obesity.

Dr James said: "The emphasis in schools is so much on academic achievement that sport promotion for children in schools is being neglected.

"But the survey saying more exercise will help tackle obesity doesn't really come as a shock."

Bolton's health bosses insisted they were working with schools to increase the levels of activity in a bid to reduce obesity.

Lesley Jones, a public health specialist with Bolton Primary Care Trust, said: "The PCT is working with its partners - including schools - with the aim of both improving children's diets and increasing their levels of physical activity.

"A balance of both these strategies is needed to tackle childhood obesity, improve children's overall health and well-being and help prevent children developing health problems in later life."

The study, which was carried out at the University of Bristol, showed that children's body fat percentage rose as their levels of activity fell.

An extra 15 minutes of moderate and vigorous activity was associated with a 50 per cent reduced likelihood of obesity in boys and almost 40 per cent in girls.

In Bolton just over 25 per cent of four and five year olds and almost 30 per cent of 10 and 11 year olds are classed as overweight or obese.

Overweight youngsters run an increased risk of developing type two diabetes - normally only found in the over 40s - by their teenage years, along with heart disease, high blood pressure and high cholesterol levels.