The 24-H Activity Cycle Among Early Adolescent Boys and Girls: Examining Cognitive Function and Mental Health
Michelle Lim, William W. Lewis-de los Angeles, Stuart J. Fairclough, Nicole E. LoganIntroduction:
To investigate how 24-h movement behaviors relate to cognition and mental health in a sex-stratified sample of early adolescents.
Methods:
Cross-sectional data from 10,972 early adolescents (47.57% female; aged 12.03 ± 0.67 yr) from year 2 of the Adolescent Brain Cognitive Development study were analyzed. Assessments included demographics, cognition (NIH Toolbox), and mental health (Child Behavior Checklist); 24-h movement behaviors (time spent in sleep, SB, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA)) were objectively measured via up to 21 consecutive days of wrist-worn Fitbit accelerometry. Compositional Data Analysis (CoDA) with 95% confidence intervals was used to model predicted changes in cognitive and mental health based on time reallocations between movement behaviors, adjusted for covariates (pubertal status, household income, BMI). Missing cognitive and behavioral data were addressed using multiple imputation, and compositional-specific imputation methods were applied to preserve the integrity of the 24-h movement composition.
Results:
In our sample, boys spent an average of 286.40 ± 56.60 min in LPA and 24.22 ± 16.58 min in MVPA time per day, while girls spent 301.28 ± 61.93 min in LPA and 10.54 ± 9.08 min in MVPA time per day. CoDA revealed sex-specific associations between 24-h movement behaviors and developmental outcomes. Reallocating 60 min to MVPA predicted better picture sequence performance observed only in adolescent girls (β = 0.92,
Conclusions:
Increasing daily MVPA for both boys and girls was associated with improved mental health in early adolescence, with additional domain-specific cognitive and mental health benefits emerging from higher MVPA in boys and higher LPA in girls. These sex-specific patterns underscore the importance of considering developmental and behavioral trade-offs when interpreting 24-h movement behavior profiles in early adolescence.