Cross-sectional and prospective associations between passive and mentally-active sedentary behaviors and academic achievement in adolescents

To analyze the cross-sectional and prospective associations of passive and mentally-active sedentary behavior (SB) with academic performance in school-aged adolescents, as well as to investigate potential gender interactions and conduct gender-stratified analyses. This school-based study was conducted in Londrina, Paraná, Brazil, in 2016, and included a sample of 664 adolescents (348 girls) aged 12 years. After three years, follow-up data were collected from 115 participants (60 girls) aged 15 years (follow-up rate: 48%). At both points, participants self-reported their daily time (hours/day) spent in mentally-passive SB (watching television and videos) and mentally-active SB (playing video games, reading, and doing schoolwork) using a questionnaire derived from the Health Behavior in School-aged Children study. Academic achievement was assessed using official school grades in Portuguese, English, Mathematics, and History from the semester in which data collection occurred. Multiple linear regression models were applied, with adjustments for potential confounders. Interaction terms were used to assess the moderating effect of gender, and stratified analyses were conducted. Overall, no associations were found between mentally-active or passive SB and academic performance in either the cross-sectional or prospective analyses for the whole sample, and the gender-interactions were not significant (p> 0.05). Prospectively, an increase of one hour in mentally-active SB was inversely associated with Portuguese grades among boys (β = -0.12, 95% CI: -0.22 to -0.03). In the cross-sectional analysis, mentally-passive SB was negatively associated with History (β = -0.09, 95% CI: -0.15 to -0.02) and English grades (β = -0.07, 95% CI: -0.14 to -0.01) among girls. Although there were no significant associations in the whole sample, stratified analyses revealed that the negative relationships between SB and academic performance differ by gender, with mentally-passive SB being more relevant for girls and mentally-active SB for boys. • The study analyzed associations between mentally active and passive sedentary behavior and school performance. • No general associations were observed between sedentary behaviors and academic performance. • Gender did not have a moderating effect on relationships. • Specific associations emerged only in analyses stratified by gender.