The purposes of this study were to examine how fitness at the baseline could predict both academic achievement and academic achievement changes one school year in advance. A total of 194 adolescents (mean age: 14.15 ± 0.97 years old, 112 boys) who attended secondary school participated in our study. Cardiorespiratory fitness was measured with the 20 m endurance shuttle-run test. We also assessed the lower-limbs muscular strength with the standing long jump test and flexibility with the sit-and-reach test. The academic achievement was assessed by school grades. We performed linear regression analyses. Additionally, we examined the relationship between fitness and changes in the academic performance following the same statistical methodology. Cardiorespiratory fitness was positively associated with mathematics one school year in advance (p = 0.025). Cardiorespiratory fitness was also positively associated with changes in Spanish language (p = 0.005), mathematics (p = 0.023), and the grade point average (p = 0.006). Muscular strength was also positively associated with changes in Spanish language (p = 0.040) and mathematics (p = 0.010), while flexibility was associated with changes in Spanish language (p = 0.039) and the grade point average (0.027). Our results suggest that cardiorespiratory fitness was positively associated with academic achievement in adolescents.
Keywords: Academic performance; adolescents; cardiorespiratory fitness; flexibility; muscular strength.