A study on the effects of compositional isotemporal substitution benefits for 24-hour activity behavior on executive functions of preschool children XU Zhihan1, 2，WANG Shiqiang1, 2，YU Aolin1, 2，CHEN Yuxin1, 2，XIAO Shunying1, 2，MA Zitong3
(1.College of Physical Education，Hunan University of Technology，Zhuzhou 412006，China2.Hunan Provincial Key Laboratory of Physical Health and Sports Fitness，Zhuzhou 412006，China3.College of Educational Science，Hunan Normal University，Changsha 410081，China)
Abstract:A cross-sectional survey was conducted on 209 preschool children aged from 3 to 6 years old in Zhuzhou, Hunan, And accelerometers were used to measure 24-hour activity behavior, and the executive function level of preschool children was evaluated by the parental version of the executive function questionnaire for preschool children (BRIEF-P). Using compositional data and isotemporal substitution model methods to analyze the relationship between the proportion of 24-hour activity behavior time and the executive functions of preschool children, as well as the expected changes in the redistribution of 24-hour activity behavior time and executive functions. The results showed that: (1) The proportion of MVPA time and the total score of executive functions in preschool children displayed significantly negative correlation(=-5.45, P=0.03), which is also between the proportion of LPA time and the total score of executive function in preschool children (=-10.67, P=0.03). But the proportion of sleep time was significantly and positively correlated with the total score of executive function in preschool children (=15.30, P=0.03), while the proportion of sedentary behavior time was not correlated with the total score of executive function in preschool children. (2) The prediction results of the 15 minute isotemporal replacement model showed that after replacing other activity behaviors with MVPA, the total score of executive function in preschool children significantly decreased, while on the contrary, it increased. Moreover, the redistribution of time between MVPA and the other three activity behaviors had an asymmetric effect on the isotemporal substitution benefit of executive functions. Among all alternatives, MVPA replacing LPA had the best effect on reducing the total score of executive functions. The research suggests that kindergartens and parents should pay attention to the comprehensive effects of 24-hour activity behavior time on preschool children, as well as the negative effects of insufficient MVPA on their executive functions. Not only should we adhere to the concept of "more activity and less sitting" in the long term, but we should also promote the transition between sedentary behavior and MVPA. At the same time, we can also increase the intensity of PA and promote the transition from LPA to MVPA, in order to promote the development of executive functions among preschool children.