Author(s): MEERITS, P.R., TILGA, H., KOKA, A., Institution: UNIVERSITY OF TARTU, Country: ESTONIA, Abstract-ID: 349

INTRODUCTION
The global trends of insufficient physical activity (PA) levels among children and adolescents underscore the imperative to identify ways to encourage their PA behavior. Both parents and teachers play a crucial role in shaping the health behaviors of children. Therefore, we developed and tested two online need‑supportive interventions based on self-determination theory, for parents and physical education (PE) teachers. The interventions consist of video lectures about need-supportive techniques that parents and PE teachers can use when interacting with children to support their intrinsic motivation towards leisure‑time PA.

METHODS
We recruited 115 children (Mage = 12.47 ± 0.68, boys = 55, girls = 60) and one parent for each child. Students were cluster-randomized by school into four study groups (PE teacher training; parent training; combined PE teacher and parent trainings; control). Respective of the group, PE teachers and parents were assigned to either participate in a 4-week need-supportive intervention program or continue teaching and parenting as usual. Children completed questionnaires on psychological measures and self‑reported PA pre‑intervention, post‑intervention, and one month after the intervention. Repeated measures ANOVAs were conducted to test the unique and combined effects of the interventions.

RESULTS
Students in the combined study group showed significantly higher perceived autonomy support from parents at one-month follow-up compared to students in either intervention alone and the control group. Contrary to expectations, the combined study group also demonstrated significantly higher perceived controlling behavior from teacher and external regulation in PE classes at one-month follow-up.

As the effect of these interventions may be moderated by the baseline PA level, we conducted additional analyses to examine whether the interventions were more effective for the sub-group of students with relatively low levels of PA at baseline. Results showed that combined study group demonstrated significantly higher levels of intrinsic motivation in PE, and perceived autonomy and competence support from parents at one-month follow-up compared to students in either intervention alone and the control group. Students in both PE teacher and parent alone intervention groups demonstrated a decline in perceived controlling behavior from PE teacher compared to the control and combined study groups at one-month follow-up.

DISCUSSION
When PE teachers and parents are involved simultaneously in supporting children’s psychological needs, the children feel more autonomy support from their parents at follow-ups. Furthermore, results indicated that these interventions may be more beneficial for children who have lower PA levels at the outset.
Future research should replicate the interventions with a larger number of participants. Also, future intervention studies are advised to select children who are currently especially low in PA.