Children in Switzerland are most active at the age of 12, according to a study released by the Federal Sport Office.
The results come from the first-ever survey carried out on the sporting habits of children aged ten to 14.
Around half of children surveyed said they partook in more than the compulsory three hours of weekly school sport. Only 14 per cent played no sports outside school.
Boys were more active than girls, the authors of the Youth and Sport study wrote, pointing out that in the case of foreigners, only a small proportion girls participated in athletics.
They also said that the higher the education of parents, the more likely children generally were to participate.
By the age of 15, enthusiasm had declined, the authors wrote.