Longitudinal associations among cardiorespiratory and muscular fitness, motor competence and objectively measured physical activity

Objectives: This study aimed to investigate cross-lagged associations in motor competence, cardiorespiratory fitness, muscular fitness and accelerometer-based moderate-to-vigorous physical activity (MVPA) engagement. Design: One-year prospective follow-up study. Methods: A sample was 491 (275 girls; M at baseline = 11.27, SD = .32) Finnish physical education students. Students’ motor competence was assessed by (1) two-legged jumping from side to side test, (2) throwing-catching combination test and (3) 5-leaps test. Their cardiorespiratory fitness was analyzed by a 20-m shuttle run test and muscular fitness by curl-up and push-up tests. Additionally, students’ MVPA was measured objectively by hip-worn accelerometers. Results: Results demonstrated that: (1) cardiorespiratory fitness measured at Grade 5 was the only significant predictor of later MVPA and this association appeared only in the boys’ group, (2) MVPA assessed at Grade 5 significantly predicted cardiorespiratory fitness in the girls’ group, (3) cardiorespiratory fitness collected at Grade 5 associated with muscular fitness, locomotor and stability skills in both girls and boys, and (4) locomotor skills measured at Grade 5 predicted significantly muscular fitness, locomotor and manipulative skills in both sex groups. Conclusions: Elementary school years are important in providing students with experiences in physical activity (PA) which leads to improvements s in cardiorespiratory health. Additionally, this study showed that cardiorespiratory fitness collected at Grade 5 associated with later muscular fitness, and locomotor and stability skills in both sex groups. These findings are noteworthy because muscular fitness in youth has several health-related benefits and motor competence in childhood and adolescence has positive association with later PA engagement.