Longitudinal changes in screen time, sleep, and sports/exercise activity in early adolescence

TL;DR

This study tracks how early adolescents in the U.S. spend their time on screens, sleep, and exercise over three years, finding that screen time increases while other activities decrease.

Contribution

The study provides new longitudinal insights into how screen time displaces other daily activities during early adolescence using data from the ABCD Study.

Findings

Screen time increased significantly over three years, with girls spending more time on digital socializing and boys on video games.

Sleep duration slightly decreased, while sports/exercise activity initially dropped but later increased.

Time spent on other activities decreased substantially as screen time increased.

Abstract

This study aimed to examine longitudinal changes in screen time, sleep, and sports/exercise activity in early adolescents in the United States.

We examined data over four annual assessments collected from the Adolescent Brain Cognitive Development (ABCD) Study (N = 9,519) from baseline (2016–2018, ages 9–10) to Year 3 (2019–2021, ages 12–13). Trends in screen time, sleep, sports/exercise activity, and other activities in a 24-hour time-use paradigm were derived from compositional data analysis, incorporating isometric log-ratio transformations and mixed-effects modeling.

Screen time increased by 0.23 h/day from baseline to Year 1, 1.58 h/day from baseline to Year 2, and 3.28 h/day from baseline to Year 3. Video game playing increased more in boys, and digital socializing increased more in girls. Sleep duration slightly decreased from baseline to Year 3. Sports/exercise activity slightly decreased from baseline to Year 1, then increased until Year 3. Time spent on other activities decreased by 0.13 h/day from baseline to Year 1, 1.60 h/day from baseline to Year 2, and 3.38 h/day from baseline to Year 3.

Our findings indicate screen time may have increasingly displaced other activities as early adolescents age.

The online version contains supplementary material available at 10.1186/s12887-025-06368-z.

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