TWOgether - From Sport Zero to Sport Hero
BACKGROUND: The physiological and psychological benefits of regular physical activity (PA) and reduced sedentary behavior are well documented. Nevertheless, the majority of adolescents in western countries, e.g., Switzerland, do not meet the recommendations for moderate to vigorous PA of at least one hour per day. Planning interventions, defined as the creation of plans when, where and how to engage in a behavior change, have been proposed as an effective way of translating intentions into action. AIM: The project aims at closing the empirical gap of the question whether or not planning interventions of PA in adolescents are successful and which planning intervention is the most effective one. In detail, it is aimed for to examine changes in (daily) moderate to vigorous physical activity in adolescents' friendship dyads following (a) an individual planning intervention, (b) a collaborative planning intervention or (c) one of the two no-planning control conditions. Changes in (daily) physical activity will be examined over a period of 6-months. By investigating the intervention effect systematically by means of daily diaries, long-term follow-ups and objective measurements this project will provide a novel knowledge about individual self-regulating mechanism and social exchange processes as the mediating mechanism of the effectiveness of individual and collaborative planning for health behavior change in adolescents. DESIGN: Single-blind four-arm parallel-group cluster-randomized controlled trial with longitudinal design. The assessment of the main and secondary outcomes is conducted at the baseline, at 1 week after the first intervention session, and at 1-, and 6-month follow-ups. The intervention consists of one planning session and one booster session after 1-month. PARTICIPANTS: The sample will consist of 400 friendship dyads between 14 and 18 years of age. A cluster-randomization will assign participants to one of the two planning groups (collaborative or individual) or one of the two control groups. Both partners of the friendship dyad will complete all questionnaires. OUTCOMES: Physical activity constitutes the main outcome, whereas self-regulatory strategies like planning, self-efficacy, as well as social exchange processes like social support are secondary outcomes.
Start: September 2018