A US study has revealed that team sport is the only extracurricular activity to make significant difference to the academic results of students.

Teenagers who belong to sports clubs compared to others such as drama or debating - are also more likely to complete their education and higher education.

The study, conducted by the University of South Carolina and Pennsylvania State University, collected data from 9,700 high school students aged between 14 and 18.

The study also revealed that teenagers living in the countryside are more likely to take part in extra-curricular activity when compared with those from cities.

The results were still true even after the students' race, sex, previous achievements and socio-economic background were taken into consideration.

Matthew Irvin, assistant professor in the Department of Educational Studies at the University of South Carolina, said: "Sport allows you to develop a mentoring relationship with adults and with positive, school-oriented peers."

Eileen Marchant of the UK's Association for Physical Education, said: "It raises self-esteem and self-belief and there's an absolute correlation between believing in yourself and what happens in other areas of the curriculum."