Trends in Patterns of Physical Exercise and Screen-Time in Swedish Adolescents From 2013 to 2019.

Adolescents' participation in physical exercise (PE) in sports clubs and self-organised training has decreased over time, while screen-time (ST) has increased. Boys exercise more and play more video games than girls, and adolescents without disabilities exercise more than adolescents with disabilities. This study aims to explore trends in patterns of PE and ST, and the association with gender and disability. Cross-sectional data from 3949 Swedish adolescents aged 12-14 and 15-18 years were used. Participation in sports, training, watching TV & movies, and playing video games was analysed annually for 2013-2019 by hierarchical cluster analysis with k means rotation. Clusters' centroids were compared across years. Associations with gender and disability were tested with regression analysis. In both age groups, five to six clusters were identified each year. Most adolescents are in exercising patterns. The proportions in patterns of sporting and ST increased between 2013-2015 and 15-18-year-olds in not-exercising patterns decreased continuously. Exercising and not-exercising patterns show stable trends, while ST patterns no longer have similar structures after 2016. More clusters in 2013-2016 than 2017-2019 are associated with gender. No cluster in 12-14-year-olds and four clusters in 15-18-year-olds are associated with disability. The study provides a new perspective on trends in patterns of PE and ST from 2013 to 2019 in Swedish adolescents. Results indicate an increased polarisation in activity patterns yet decreased polarisation between genders, and that adolescents with disabilities have the same activity patterns as other adolescents. Further research into other factors potentially influencing adolescents' activity patterns is needed.