Effects Of Acute Exercise On Cognitive Function In Different Exposures

Since the outbreak of haze in 2013, it has been endangering the quality of life and health of Chinese people. Exposure to air pollution can hinder the cognition development of children and adolescents. Middle school students are at the key point of entering school, cognitive function plays a decisive role at this time, and even determines the development of students' whole life. High intensity interval Training (HIIT) has been shown to improve cognitive development, but HIIT may cause the body to inhale more pollutants. This contradiction needs to be resolved urgently. PURPOSE: The aim of this study is to balance the beneficial effects of exercise with the harmful effects of air pollution on cognition. So as to lay a foundation for future long-term intervention experiments in schools and other institutions. METHODS: Sixty-seven middle school students (age 15 ± 1.8) were randomly divided into HIIT group (N = 40) and control group ( N = 27). The subjects in the HIIT group were required to complete a 30s sprint in a specified distance of 20 m, followed by a 30s rest interval, which repeated five times. We required the subjects to sprint at 80-90% of their maximum heart rate each round. The CON group did not receive any exercise intervention. The subjects in the HIIT group underwent Yo-Yo test one week before the acute HIIT, and the maximum heart rate in the last 1 minute was recorded as the maximum heart rate of the subjects. Subjects in the two groups were tested for cognitive function (executive function and processing speed) before and after the 30 minutes exercise or rest. At the same time, air quality was measured using an air monitor, including PM2.5, PM10 and CO2. RESULTS: When the covariate (PM2.5 and PM10) was not controlled, it was found the interventions only had a significant effect on the mean response to executive function (F = 4.309, P = 0.042, ηp2 = 0.062). However, when the PM2.5 and PM10 were controlled, the effect of interventions on the mean response time was no longer significant. On the contrary, PM2.5(F = 5.791, P = 0.010, partial ηp2 = 0.083) and PM10(F = 6.893, P = 0.011, ηp2 = 0.117) had a more significant effect. CONCLUSIONS: Acute HIIT may improve some cognitive function, but air pollution is likely to counteract this effect, and the effect of air pollution on cognitive function is greater than that of exercise intervention.