Mechanisms of physical activity behaviour change in adolescent girls

• Applicant: Professorin Dr. Yolanda Demetriou
• Subject Area: Educational Research on Socialization, Welfare and Professionalism
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 393984985

Physical inactivity is deemed to be the fourth leading cause for premature death. Nevertheless, only a minority of children and adolescents in Germany fulfil the guideline of the WHO of at least 60 minutes of moderate-to-vigorous physical activity per day. Children and adolescents with a lower socioeconomic background and especially girls are regarded as a high-risk group in terms of physical inactivity.By conducting a cluster randomised controlled trial with 600 sixth grade girls of the Bavarian Mittelschule, it will be examined how a theory-based intervention programme implemented in physical education lessons affects physical activity both during these lessons and in leisure time. Based on the self-determination theory and the social cognitive theory, the promotion of autonomy, competence, relatedness, social support and self-efficacy in girls will form the core of the intervention programme. In a further step, it will be examined to what extent these constructs mediate the effect of the intervention programme on the girls physical activity. Moreover, the potential moderating role of socioeconomic status, environmental factors, teacher characteristics and BMI will be tested. The intervention will be carried out by the physical education teachers of the participating classes for five months followed by a follow-up period of three months. The physical education teachers will be trained by staff of the Technical University of Munich.The girls physical activity will be measured by accelerometers and systematic observations. Questionnaires will be used to quantify their values in the potential mediators and moderators. All measurements will be conducted three times (baseline, post-intervention, follow-up). The lesson content of the waiting control group remains unchanged until the follow-up assessment. Applicability of the questionnaires, accelerometers, intervention components and the feasibility of the teachers training will be pilot tested in advance to be able to make adaptations before beginning of the main study. Statistical analyses will be done by structural equation modeling in Mplus.

• DFG Programme: Research Grants