Boys who play sport or take part in after-school clubs are more likely to do well in exams, according to research that suggests a healthy body really does lead to a healthy mind.

Cricket, orienteering and even bell-ringing improves the academic achievements of pupils at private schools, researchers at the Independent Schools Council (ISC) say.

The difference that extra-curricular activities make to boys’ exam performance is more marked than the effect on girls at GCSE, they found.

Andrew Halls, head of King’s College School for boys in Wimbledon, South London, where pupils have activities in place of lessons on Friday afternoons, said that his pupils needed stimulation outside the classroom to do well in exams. “Boys really want a hinterland to their studies. They don’t want to work in a vacuum and need a sense of life beyond the classroom to make the classroom more palatable,” he said. “Girls tend to weather tedium better than boys. If their lessons are boring, girls will compensate for that, whereas with boys it explodes in your face a bit.”

Researchers compared the number of activities on offer at 508 member schools of the ISC with their academic performance at GCSE. Those offering more clubs and sporting opportunities had better results.

Tim Hands, head master of Magdalen College School, Oxford, where 91 per cent of boys achieved As or above at GCSE in 2007, said: “There is a pretty dramatic correlation between those who take on a major activity — whether it is starring in a play or captaining the first XI cricket team — and getting first-choice universities after A Level or doing particularly well at GCSE. People benefit from having commitments across the board. They have got a sense of focus and perspective.”

Schools with 30 different options outside lesson time had 100 per cent of pupils all gaining Bs or above in GCSE, the study showed. Those offering fewer than 20 activities had 10 per cent of pupils gaining Bs or above.

Clarissa Farr, high mistress of St Paul’s School for Girls, said that girls benefited just as much from extracurricular activities as boys. “A broad range of activities is fundamental to academic success,” she said.

Previous studies have suggested a strong positive link between pupil participation in sport and academic achievement but have not found a gender difference.

Jacquelynne Eccles, of the psychology department at the University of Michigan, said that her study into the link between sporting activity and academic attainment found no gender divide. “But if there is a difference, it would be in that direction because the boys would be the ones that take up the sports most,” she said.

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