Does Physical Fitness Relate to Academic Achievement in High School Students?

BACKGROUND Academic achievement (AA) is an important issue not only during the school period since it is a strong predictor of long-term professional and social success. Physical fitness (PF) components are associated with AA, and previous studies were conducted with relatively small samples, lack of statistical power, and the conclusions are based on simple correlational analyses. The objective of this study was to analyze the association between PF (single and clustered) with AA in a large and representative sample of high school students. METHODS Cross-sectional design study conducted with 911 students, aged 13-15 years (38.52% boys) enrolled in the first year of high school. Cardiorespiratory fitness (20-m shuttle run test), muscular strength (dynamometer), and body composition (skinfolds) were measured. PF components were clustered (Z-cardiorespiratory fitness + Z-muscular strength - Z-body fatness). AA was analyzed through standard math tests. Hierarchical linear regression analysis was applied to verify the independent contribution of each single component and PF's cluster on AA. Age, screen time, maternal education, race, and type of residence were used as covariates. RESULTS Among boys, cardiorespiratory fitness was negatively associated with AA (β = -0.137; P = .041), while strength was positively associated with AA (β = 0.188; P = .004). There was no association between clustered PF indicators and AA (β = 0.064; P = .297). There was a negative association between age and AA in girls (β = -0.151; P = .003) and in boys (β = -0.128; P = .045). CONCLUSIONS These results support current literature, indicating an association between PF's component, namely muscular strength and AA (mathematics) in adolescents, even when controlled for several covariates.