Tracking of physical activity behaviours during childhood, adolescence and young adulthood: A systematic review

Abstract

Aim: To conduct a systematic literature search to identify studies providing data on the tracking of physical activity behaviours in children and young people. Methods: Seven bibliographic databases were searched systematically in July-August 2008 using search strategies built around three groups of keywords: physical activity, study type and young people. Studies included in the review had to be prospective, longitudinal studies that reported data on any physical activity behaviour for at least two time-points (two or more years apart). The study was restricted to community-based populations who were 18 years or younger at baseline. Two reviewers independently undertook data extraction from all suitable papers, and performed quality appraisal.  Results: The database search yielded a total of 10,685 titles, from which 59 were included in the review. There were only 15 papers that specifically examined tracking of physical activity behaviours. Tracking co-efficients ranged from -0.11 to 0.59; all indicating low or moderate tracking of physical activity, with no clear differences between males and females. Moderate tracking was observed in studies where follow-up was five years or less. The highest degree of tracking was observed for club sport participation and even over long follow-up, sports training and organized physical activity showed higher tracking than other physical activity behaviours. Physical activity levels declined consistently during adolescence, as did sports participation. However, the decrease in physical activity was less marked among those who participated in sports in early adolescence, and those who participated with parents or at high levels. The likelihood that young people continue with specific sports over short periods is generally low, but the likelihood that they continue to take part in any team, individual or vigorous activity is higher. There were no studies that evaluated the effect of sports participation during early childhood on later physical activity behaviours. Conclusions: In general, tracking of physical activity behaviours between childhood, adolescence and young adulthood is low, although there is limited evidence. The study has confirmed that levels of physical activity decrease with age, indicating the need to develop and test interventions to promote activity. Research is also needed to explore the reasons why adolescents and young adults give up physical activity and participation in sports. However, several factors in adolescence (participation in organised sports, participation with parents and high levels of participation) do lessen the chances of being inactive at a later age.