ObjectivesTo investigate the effect of combined aerobic and coordinative exercise on retinal microcirculation and its association with changes in cognitive performance in healthy adolescents. DesignUsing cluster-randomization (on class-level), 36 participants were allocated to an exercise group (EX) performing a 20-min aerobic and coordinative exercise session on each school day over a period of 8 weeks or a control group, which was encouraged to have social interactions (CON). MethodPrior to and following the intervention period, central retinal arteriolar (CRAE) and venular diameters (CRVE) were assessed by use of a static vessel analyzer. Additionally, a computer-based version of the Stroop Color-Word task was administered to assess inhibitory control. ResultsThe statistical analysis revealed that EX compared to CON showed higher CRAE at post-test, when pre-test values were accounted for, F(1,32)=4.92, p=0.036, η2=0.130. In contrast, no such effect was reported for CRVE. With regard to cognitive performance, a greater reduction of reaction time on the Stroop task was observed in EX relative to CON, F(1,30)=8.58, p=0.006, η2=0.222. The increase in CRAE was significantly correlated with a decrease of reaction time on trials demanding inhibitory control, even after adjusting for covariates, r(31)=−0.438, p=0.011. ConclusionsA structured exercise program leads to a widening of retinal arteriolar diameters, which is associated with improvements in inhibitory control. Consequently, daily exercise sessions performed during the school break-time can be recommended for promoting both cardiovascular and cognitive health in adolescents.