Effects of High-Intensity Interval Training on Executive Functions in College Students: Evidence from Different Doses

Background: Different doses of high-intensity interval training (HIIT) may affect individuals’ executive functions (EF). In this study, low-dose HIIT and moderate-dose HIIT were used to explore different doses of HIIT in terms of the impact on the EF of college students. Methods: All the participants were randomly divided into three groups. One group was not assigned any HIIT, which was called the control group. One group was assigned one session of HIIT/week, which was called the low-dose group. The last group was assigned wo sessions of HIIT/week, which was called the moderate-dose group. All groups were subjected to EF measurements. The first measurement comprised an EF a baseline measurement (Time 1) before the experiment began; the second measurement was taken (Time 2) after 6 weeks; the third measurement was taken (Time 3) after 12 weeks. Results: Time 1: We found that there was no significant difference in EF among the groups (p > 0.05). Time 2: The moderate-dose group and low-dose group improved in terms of EF. However, the improvement effect was different, and the improvement effect of the moderate-dose group EF was better than that of the low-dose group. The second measurement, EF was better for all exercise groups than for the control group. Inhibition test (reaction time: 3.97–8.24%, p < 0.05, effect size: 0.413); cognitive flexibility (accuracy: 6.66–7.32%, p < 0.05, effect size: 0.203; reaction time: 5.55–7.49%, p < 0.05, effect size: 0.521); working memory (accuracy: 4.05–4.69%, p < 0.05, effect size: 0.515; reaction time: 2.73–5.42%, p < 0.05, effect size: 0.430). Time 3: the moderate-dose group and low-dose group showed a downward trend in terms of EF. Conclusion: Low-dose HIIT and moderate-dose HIIT improved the EF in college students, but moderate-dose HIIT was better. This study suggests that moderate-dose HIIT should be adopted to improve the EF in college students.