The relationship between physical fitness and academic achievement in middle school students in Shanghai
Keywords: Shanghai
RDM2021
Physical fitness
Academic achievement
Middle school students
Quantitative research
RDM
Secondary data analysis

The relationship between physical fitness and academic achievement in relation to children and adolescents has received attention from an increasing number of researchers in various fields across the world. Large bodies of literature based on insights from neuroscience have reported a positive relationship between the overall or some specific components of physical fitness and academic achievement in different educational contexts. Furthermore, many neuroscientists have revealed that the mind and body are connected through the mechanisms of neurochemistry. It has been found that performing physical exercise can optimise the brain’s cognitive functions by stimulating brain-derived neurotrophic factor (BDNF) release, thus contributing to brain development. Physical exercise can also increase the level of neurotransmitters such as dopamine, serotonin and noradrenaline, which can improve concentration and positive emotional states for learning. However, the research findings are still under debate due to inconsistencies between studies conducted in school settings, where the results are more likely to be influenced by various confounding factors.
Although numerous studies have been conducted on K-12 school-aged children in different educational settings around the world, few have been implemented in the specific context of Chinese adolescents in the middle school period of their education. It is necessary to pay more attention to this group of students experiencing considerable body shape changes in the developmental stage of puberty. Many previous studies employed a single cohort, crosssectional design for their inquiries into this research topic. Such a design fails to explore the longitudinal trajectory in the course of the process. In order to further explore and extend knowledge regarding this topic, the present study aimed to examine the longitudinal relationship between each component of physical fitness and academic performance in three core subjects in the context of an urban middle school in Shanghai, China. This study utilised secondary data from one public middle school in Shanghai. The Chinese National Student Physical Fitness Standard (CNSPFS), which covers body mass index (BMI), agility fitness, muscular strength fitness and aerobic endurance fitness, was adopted. Standardised tests for Chinese (as a native language), Mathematics and English (as a foreign language) were also used. Data were drawn from two cohorts (Class 2015 and Class 2016) of now-graduated students from between Years 7 and 9, when they were aged 12–15 years old. The total sample of 557 participants (312 boys, 245 girls) was utilised for all data analyses by taking advantage of the statistical techniques of correlation and structural equation modelling (SEM). The researcher analysed the data by gender and controlled for cohorts and BMI in the longitudinal SEM models for the purpose of minimising the confounding factors.
The results from correlation analysis showed that there were some weak but positive relationships between physical fitness and academic achievement in the three core subjects among middle school students from Years 7 to 9 (r range from .11 to .28, p < .05). Interestingly, the relationships were generally found more frequently among boys than girls, and fewer associations were found between BMI and academic achievement compared to the other three types of performance-related physical fitness. In addition, more positive correlations were found between the level of aerobic endurance fitness and academic attainment for both boys and girls. The results from the longitudinal SEM analysis indicated more than one component of physical fitness could significantly predict academic achievement to some degree at one or more time points across the three academic years (β range from .09 to .33). Although the effect of each component of physical fitness was found to be unstable across three years and slightly different by gender, it is worth mentioning that aerobic endurance fitness could significantly predict academic achievement in all three subjects for both boys and girls, particularly in English.
Although positive relationships were found in this study, direct causality cannot be determined. The findings of this present study may provide recommendations for future studies on this research topic. In addition, the results may provide useful suggestions for educational practice in schools and for curriculum reform. It is hoped the findings will help to improve the physical fitness level of adolescents and enhance the effectiveness of academic learning, thus facilitating healthier education in the middle school stage.