Yuan Liu, Chenyang Zhao, Zheping Gu, Hong Jun, Yanyan Hu, He Liu, Xiaojian Yin
Executive function (EF) is a core component of human cognitive performance. This study investigated whether increasing the duration of moderate-to-vigorous physical activity (MVPA) could enhance this critical cognitive ability in Chinese adolescents. Adolescents (13.4 ± 0.5 years) from two secondary schools in Jiangsu Province were recruited, screened, and individually randomized into an intervention group (n = 101) and a control group (n = 105); after three withdrawals, the final analytical sample comprised 98 and 105 participants, respectively. EF was compared using independent and paired sample t-tests, analysis of covariance (ANCOVA), and effect size tests. Post-intervention, adolescents in the intervention group showed a significantly longer daily MVPA duration than the control group (mean difference 25.16 min, p < 0.05). As an exploratory analysis, sex-stratified ANCOVAs were conducted. After adjusting for pre-intervention inhibition control reaction times (RTs), ANCOVA revealed that boys in the intervention group had a lower mean inhibition control RT (1.03 ms lower than controls, p < 0.05). With pre-intervention 2-back RTs as a covariate, ANCOVA indicated significant reductions in mean 2-back RTs for intervention group boys (191.09 ms lower, p < 0.05) and girls (175.62 ms lower, p < 0.05). After adjusting for pre-intervention cognitive flexibility RTs, boys in the intervention group also exhibited a significantly lower mean cognitive flexibility RT (102.7 ms lower, p < 0.05). In conclusion, a combined aerobic and resistance (HIIT) exercise intervention effectively increased adolescents' physical activity time, and concurrent improvements were observed in key components of human cognitive performance-specifically inhibition control, working memory, and cognitive flexibility in boys and working memory in girls.