title: A systematic review of school-based interventions targeting physical activity and sedentary behaviour among older adolescents.
abstract: Lack of physical activity (PA) and high levels of sedentary behaviour (SB) have been associated with health problems. This systematic review evaluates the effectiveness of school-based interventions to increase PA and decrease SB among 15-19-year-old adolescents, and examines whether intervention characteristics (intervention length, delivery mode and intervention provider) and intervention content (i.e. behaviour change techniques, BCTs) are related to intervention effectiveness. A systematic search of randomised or cluster randomised controlled trials with outcome measures of PA and/or SB rendered 10 results. Risk of bias was assessed using the Cochrane risk of bias tool. Intervention content was coded using Behaviour Change Technique Taxonomy v1. Seven out of 10 studies reported significant increases in PA. Effects were generally small and short-term (Cohen'sdranged from 0.132 to 0.659). Two out of four studies that measured SB reported significant reductions in SB. Interventions that increased PA included a higher number of BCTs, specific BCTs (e.g., goal setting, action planning and self-monitoring), and were delivered by research staff. Intervention length and mode of delivery were unrelated to effectiveness. More studies are needed that evaluate long-term intervention effectiveness and target SBs among older adolescents.
authors.affiliation: Department of Social Research, University of Helsinki , Helsinki , Finland.
authors.forename: S-T
authors.initials: ST
authors.lastname: Hynynen
authors.affiliation: Department of Health Sciences, Faculty of Earth and Life Sciences and the EMGO Institute for Health and Care Research, VU University Amsterdam , Amsterdam , The Netherlands.
authors.forename: M M
authors.initials: MM
authors.lastname: van Stralen
authors.affiliation: Institute of Health & Society, Newcastle University , Newcastle upon Tyne , UK.
authors.forename: F F
authors.initials: FF
authors.lastname: Sniehotta
authors.affiliation: Institute of Health & Society, Newcastle University , Newcastle upon Tyne , UK.
authors.forename: V
authors.initials: V
authors.lastname: Araújo-Soares
authors.affiliation: Behavioural Science Group, Primary Care Unit, University of Cambridge , Cambridge , UK.
authors.forename: W
authors.initials: W
authors.lastname: Hardeman
authors.affiliation: Department of Public and Occupational Health and the EMGO Institute for Health and Care Research, VU University Medical Center , Amsterdam , The Netherlands.
authors.forename: M J M
authors.initials: MJ
authors.lastname: Chinapaw
authors.affiliation: UKK Institute for Health Promotion Research , Tampere , Finland.
authors.forename: T
authors.initials: T
authors.lastname: Vasankari
authors.affiliation: Department of Social Research, University of Helsinki , Helsinki , Finland.
authors.forename: N
authors.initials: N
authors.lastname: Hankonen
keywords: adolescents; behaviour change techniques; physical activity; school-based intervention; sedentary behaviour