Fidanka Vasileva

This study aimed (1) to explore the association between body composition [fat-to-muscle ratio (FMR), waist circumference (WC), and body mass index (BMI)] with motor competence (MC) and physical fitness (PFI) in 7-year-old children; (2) to ascertain whether FMR modifies the associations between MC and PF. A total of 164 children (7 yr) were included. Anthropometric (fat and muscle mass were calculated with TANITA), motor competence (CAMSA test) and physical fitness (1/2 mile run, handgrip strength, 10 × 5, standing long jump, and sit and reach tests) variables were collected. FMR, WC and BMI correlated negatively with MC (all between r ≤ −0.333 and −0.183 and p < 0.05) and PFI (all between r ≤ −0.410 and −0.246 and p < 0.05) in all children. However, the associations were stronger for FMR. In linear regressions analyses, only FMR was independently and negatively associated with MC and PFI, explaining 12.6% and 20.9% of its variance, respectively. Positive correlations between PFI and MC existed. Also, the association was not modified by FMR levels, since in both groups (above and below FMR median), the associations were maintained (p < 0.0001). However, the t-test showed that children with higher FMRs have lower levels of MC (p = 0.005) and PFI (p < 0.0001). FMR may be the best body composition parameter related to MC and PFI. Furthermore, the association between MC and PFI is not modulated by FMR but children with higher FMRs show lower levels of MC and PFI.

Brain-derived neurotrophic factor (BDNF) is a protein involved in synaptic transmission and neuronal plasticity, which underlie the processes of learning and memory formation. Acute exercise and exercise training increase BDNF concentration. We aimed to evaluate the effects of a 3-month integrated neuromuscular training (INT) on salivary BDNF concentration and the mastery of fundamental motor skills in school-aged children. An additional goal was to explore the associations between potential changes in BDNF and fundamental motor skills. Sixty-seven primary school-aged children were randomly allocated to control (N = 32; 7.52 ± 0.31 y) or INT groups (N = 35; 7.56 ± 0.29 y). A 3-month INT was applied during the warm-up of physical education (PE) classes, twice weekly. Salivary BDNF was measured using a sandwich-enzyme-linked immunosorbent assay and the mastery of fundamental motor skills was assessed using the CAMSA test, at baseline and after 3 months. The children in the INT group, as compared to the children in the control group, exhibited higher salivary BDNF (F = 8.865; p = 0.004), higher scores for sidestep (F = 13.240, p = 0.001), 1-foot hop (F = 11.684, p = 0.001), kick (F = 4.010, p = 0.050), the sum of locomotor skills (F = 18.799, p < 0.0001), and the sum of control and manipulative skills (F = 8.151, p = 0.006), as well as the total sum of fundamental motor skills (F = 11.266, p = 0.001) after the 3 months. Interestingly, the increase in salivary BDNF concentration after the 3-month INT was associated with an improvement in locomotor skills (beta = 0.385; p = 0.039; adjusted R² = 0.088) and the total improvement in fundamental motor skills (beta = 0.428; p = 0.020; adjusted R² = 0.124). A school-based 3-month INT increased salivary BDNF and improved the mastery of fundamental motor skills in children, highlighting the positive impact of this intervention for a pediatric population.