A Longitudinal Study On The Relationship Between Physical Fitness Level For Preschool Children And Cognitive Ability

Objective: Physical fitness in early school age has a positive effect on cognitive ability,however,most of the cross-sectional studies are conducted,and the longitudinal studies have a short follow-up time,and the independent effect between the two remains to be further verified.Therefore,this study aims to explore the longitudinal correlation between the physical fitness level of preschool children and their cognitive ability 3 years later,and to further explore whether the relationship between the two is independent of the baseline cognitive level.To provide reference for the study of cognitive development in early life.Methods: This study was a longitudinal follow-up study.Firstly,306 preschoolers(average age 4.8 years)in Shanghai were recruited for baseline comprehensive physical fitness assessment and cognitive ability test during 2013-2014,and follow-up tests were completed during 2016-2017.The comprehensive assessment of physical fitness adopted the National Fitness Measurement Standards Manual The evaluation criteria for(Children’s Part),and the indicators included children’s height,weight,20 meters shuttle-run test,handgrip-strength,standing long-jump tests,and 2 × 10 meters shuttle run.After the height and weight were scored according to the Manual,the Physical Fitness T-score(PFT)was calculated by combining with the standardized scores of other indicators.The children’s Verbal intelligence quotient(VIQ),Performance intelligence quotient(PIQ)and Full intelligence quotient(FIQ)were assessed by using the urban version of "China-Wechsler Intelligence Scale for Children(C-WYCSI).On this basis,the baseline PFT and each index were divided into three groups,at the lowest level set for the reference,A mixed linear regression model with cognitive ability as a result,physical health level as a fixed factor,and kindergarten nature(public/private)as a random effect was adopted(Model 1:unadjusted;Model 2: Adjust for age,sex,mother’s highest education,family income,behavioral score,and baseline physical activity;Model 3: Model2+ adjusted baseline cognitive ability).First of all,examined the dose-response relationship between the baseline PFT and baseline cognitive ability(Model 1,Model2);Second,examined the dose-response relationship between the baseline PFT and follow-up cognitive ability,(Model 1,Model 2,and Model 3).Finally,examined the relationship between PFT and changes in performance(X1-X0)on each of the two tests and follow-up cognition(Model 1,Model 3).Results: A total of 123 participants completed the follow-up test and were included in the final statistical analyses(75 boys and 48 girls,with the mean age was 7.9±0.4years).After adjusting for confounding factors(age,sex,mother’s highest education,family income,behavioral score,and baseline physical activity),there was a significant positive correlation between baseline physical fitness and baseline cognitive ability.Each 10-point increase in baseline PFT was associated with an increase in baseline VIQ and FIQ by 0.4(95%CI: 0.2-0.6)and 0.9(95%CI: 0.1-1.8),respectively,and there was a significant dose-response relationship between the two.There was also a significant positive correlation between baseline PFT and follow-up FIQ,with a 10-point increase in PFT at pre-school age associated with a 0.9 point increase in FIQ three years later(95%CI: 0.2-1.5).However,baseline PFT was not significantly associated with VIQ,PIQ,and FIQ at follow-up when adjusted baseline cognitive ability was increased.Similarly,there was no statistically significant relationship between the changes in PFT and scores of various indicators during the two tests and VIQ,PIQ and FIQ during follow-up.Conclusion: Better physical fitness of preschoolers was significantly associated with higher cognitive ability three years later.The higher the physical fitness level of the preschool children at the age of 4 to 6 years,the better their cognitive ability level three years later.But the relationship is not independent of baseline cognitive ability.It is suggested that building and improving activities based on physical fitness in the early school age and maintaining good physical fitness level are beneficial to the development of cognitive ability in the future.