Physical activity and executive function in adolescents: Dual rumination pathways and mindfulness moderation

BACKGROUND: Late adolescence is a developmental period in which executive functions are relatively consolidated but remain sensitive to behavioral and environmental influences. Physical activity (PA) has been associated with executive-function outcomes, but the psychological factors that may be related to this association remain unclear. Objective: This study examined whether PA_total was associated with a reaction-time-based executive-function composite (EF_RT) through intrusive rumination (IR) and deliberate rumination (DR), and whether mindfulness moderated the PA_total → IR and IR → EF_RT associations. METHODS: Late adolescents (N = 450; 266 males; aged 17-19 years) completed measures of PA, rumination, and mindfulness. EF_RT was derived from standardized RT-based indicators from computerized Flanker, 2-back, and More-Odd Shifting tasks. Lower EF_RT values indicate better RT-based task performance. Structural equation models were used to test parallel indirect associations and observed-variable interaction terms, with gender included as a covariate. Bias-corrected bootstrapping with 5,000 resamples was used to estimate indirect and conditional indirect associations. RESULTS: PA_total showed significant positive total and direct associations with EF_RT, indicating that higher PA_total was associated with higher RT-based scores, that is, slower or less efficient RT-based task performance. Significant indirect associations were observed through both IR and DR. Mindfulness moderated the PA_total → IR and IR → EF_RT associations, and the conditional indirect association through IR varied across levels of mindfulness. Because EF_RT is a reaction-time-based composite, positive coefficients involving EF_RT indicate higher RT-based scores, reflecting longer reaction times or larger RT costs, rather than better EF ability. CONCLUSIONS: PA_total, rumination, mindfulness, and EF_RT were interrelated in late adolescents. The findings should be interpreted as cross-sectional associations involving RT-based executive-function performance, including an unexpected positive PA_total-EF_RT association indicating slower or less efficient RT-based performance, rather than as evidence of causal effects on EF ability.