Exercise alone 'will not beat childhood obesity'

Exercise alone plays only a small role in determining a child's weight, new research suggests.

A study published in the Archives of Disease in Childhood found that fewer than half of boys and just one in eight girls manage to meet the recommendations for weekly physical activity.

While some children exercise for more than 90 minutes per day, others are regularly active for less than ten minutes a day.

Despite the wide variation, researchers from the Peninsula Medical School in Plymouth found that the amount of exercise a child does has little effect in his or her weight or body mass index (BMI).

Lead researcher Professor Terry Wilkin told the Plymouth Evening Herald that BMI is a "very blunt tool" as it "doesn't pick up any difference for those children who do and don't meet physical activity guidelines".

However, he noted that blood tests confirm that children who exercise do benefit metabolically.

He added: "Children who do more exercise benefit, but we still have no idea how to encourage those who do not meet the deadline to do more."