Rationale Obesity is a growing problem in the UK. The problem of obesity is also affecting children and with that come significant health, social and economic concerns. Lack of physical activity in children is evident. Physical activity is also beneficial for tackling obesity as well as other positive health and lifestyle outcomes.

Aims We aim to investigate what children understand by the term exercise and what facilitates and prevents them from being active or taking part in sport and exercise.

Subjects and methodology Qualitiative study using focus groups in 11–14 year old school children in Slough to identify their attitudes and beliefs towards exercise. Children were selected from a local slough grammar school.

Results Several themes were identified which were facilatitive or perceived as barriers towards exercise. It was interesting to further discover differences in the barriers between the female and male groups and participants from ethnic minorities.

Conclusion By understanding the beliefs and attitudes towards exercise of 11–14 year old children in Slough we may be able to develop and improve behavioural interventions to encourage exercise in this group. Further study into the barriers and facilitators of adolescent girls and ethnic minority children may be important to develop participation of the groups in physical activity.