Adolescent physical activity improves quality of life via self-efficacy

This study provides insight to the mechanisms linking physical activity to quality of life among adolescents, pointing to specific aspects that physical activity-promoting interventions may address.

Background
Although most adolescents in Norway report good mental health and quality of life, a decline over the past decade has been shown. Good mental health and quality of life is crucial both for the individual adolescent and for society’s sustainability, which emphasizes the need to identify factors that can contribute to reversing the observed trend. Physical activity has been identified as a key factor in this matter. However, there is lack of knowledge on the mechanisms relating physical activity to improved quality of life. A better understanding of the pathways through which physical activity may affect quality of life among adolescents could lay the ground for more specific and effective health promoting interventions. Increased general self-efficacy has been proposed as a potential mechanism for the quality of life-improving effect of physical activity, but there exists scarce research on the topic. Thus, the aim of this study was to examine whether general self-efficacy mediates the relationship between physical activity and quality of life among adolescents. Also, as such a mediation effect may vary in subgroups of the adolescent population, we investigated whether this differed by gender and age.

Methods
The study applied a cross-sectional design based on data from the Ungdata survey in Vestfold and Telemark from 2021. A sample of 18,146 adolescents from lower and upper secondary schools were included in the analyses, based on respondents who had completed all items relevant for the study. The following variables were included: physical activity, quality of life, general self-efficacy, gender, age, family socio-economic status, and social support. Data were analyzed using the Statistical Package for Social Sciences (SPSS) with the PROCESS macro, including mediation and moderated mediation analyses through multivariate regression analyses.

Results
The results showed that physical activity was positively associated with quality of life, particularly among girls and older adolescents. Physical activity was also positively associated with general self-efficacy, for both genders and all ages. General self-efficacy was positively linked to quality of life, especially for girls and younger adolescents. The findings confirmed the study’s hypothesis, as general self-efficacy was found to contribute to the mediation of the relationship between physical activity and quality of life, with the strongest effects for girls and younger adolescents.

Conclusion
This study suggests that increased general self-efficacy is an important pathway through which physical activity can promote adolescents’ quality of life, for all adolescents, but to a higher degree for girls and the younger adolescents.