Association between physical fitness index and executive function in Chinese Tibetan adolescents aged 10–12

OBJECTIVE: Examine the associations between Physical Fitness Index (PFI) and specific executive function (EF) subdomains (inhibitory control, working memory, cognitive flexibility) among Tibetan adolescents aged 10-12 years in China's high-altitude areas. METHODS: A total of 376 Tibetan adolescents (184 boys, 192 girls) aged 10-12 years were recruited from four cities in the Tibet Autonomous Region (Lhasa 3650 m, Nagqu 4500 m, Qamdo 3500 m, Nyingchi 3100 m) using stratified cluster random sampling. PFI was calculated from grip strength, sit-ups, standing long jump, 20-s side shuffles, sit-and-reach, 50-m sprint, and 20-m shuttle run (20mSRT). EF was assessed using the Flanker task (inhibitory control), 1-back task (working memory), and More-odd Shifting task (cognitive flexibility). Hierarchical regression analyses were performed to examine the relationship between PFI and EF after adjusting for age, sex, BMI, waist circumference, moderate-to-vigorous physical activity, weekly sleep duration, and city. RESULTS: PFI was significantly negatively associated with congruent and incongruent reaction times (RTs) from the Flanker task, as well as with working memory and cognitive flexibility RTs. However, PFI was not significantly associated with the Flanker interference effect (incongruent minus congruent RT), which specifically indexes inhibitory control (P > 0.05). After covariate adjustment, higher PFI correlated with faster working memory (P < 0.05) and cognitive flexibility (P < 0.01), but not with the interference effect. CONCLUSIONS: Among Tibetan adolescents aged 10-12 years living at high altitude, higher physical fitness index is associated with better working memory and cognitive flexibility, but not with the Flanker interference effect.