The Relationship between Physical Activity Levels, Cardiorespiratory Fitness and Academic Achievement School-Age Children from Southern Spain

The relationship between physical activity (PA), cardiorespiratory fitness (CRF) and academic achievement in young people is unclear. The aim of this study was to analyze the relationship between PA, CRF and academic achievement in 152 children according to sex (average age of 8.6 ± 0.3 years) in southern Spain. A tri-axial accelerometer was used to measure PA; the 20-m Shuttle Run Test was performed to assess the CRF; and to know the academic achievement, the official school records were considered. The results showed a weak correlation between moderate PA and moderate-to-vigorous PA (MVPA) with CRF in boys (all, 0.2 > r < 0.4; p < 0.05), whereas the vigorous PA showed a moderate and weak correlation with CRF (all, p < 0.05), in both boys (r = 0.537) and girls (r = 0.382), respectively. In addition, a weak inverse correlation between moderate PA and MVPA with academic achievement showed in girls (all, 0.2 > r < 0.4; p < 0.05). Finally, the CRF weakly correlated with academic achievement only in boys (all, 0.2 > r < 0.4; p < 0.05). Our study showed a relationship between PA and CRF in both sexes. Nonetheless, the PA was inversely related to academic achievement in girls, whereas the CRF was related to academic achievement in boys.