Children who exercise regularly while growing up are more likely to perform better in academic tests when they are older, research suggests.
Moderate to vigorous exercise particularly seems to help girls do better in science, according to a report from the Universities of Strathclyde and Dundee.
The exercise and school studies of around 5,000 teenagers, who were part of the 'Children of the 90s' health study, were analysed.
The duration and intensity of the children's daily physical activity levels were measured for periods of between three and seven days, when they were aged 11, using a device called an accelerometer, worn on an elasticated belt.
The accelerometer showed that the average daily number of minutes of moderate to vigorous exercise the 11 year olds clocked up was 29 for boys and 18 for girls.
The children's academic performance in English, maths, and science was then assessed at the ages of 11, 13 and 15 or 16.
The analysis showed that better results across all three subjects was linked to the amount of moderate to vigorous physical activity undertaken at the age of 11.
By the age of 15/16 exam results showed an increase in performance for every additional 17 minutes per day boys did and 12 minutes per day that girl spent doing intensive exercise at the age of 11.
The performance of girls in science subjects was particularly high among those who exercised regularly at 11, the report found.
The study was led by Dr Josephine Booth, from the University of Dundee, and Professor John Reilly, from Strathclyde University, in collaboration with teams from the Universities of Georgia and Bristol.
It is published in the British Journal of Sports Medicine and the authors said they will conduct further research to confirm their initial findings.
The report concluded : "This is an important finding, especially in light of the current UK and European Commission policy aimed at increasing the number of females in science subjects.
"If moderate to vigorous physical activity does influence academic attainment this has implications for public health and education policy by providing schools and parents with a potentially important stake in meaningful and sustained increases in physical activity."