## 3 Results
### Associations Between Body Composition, Motor Competence and Physical Fitness Index  
Table 2 shows that the FMR, WC and BMI correlate negatively with MC (all between r \(\leq-0.333\) and \(-0.183\) and \(p\) < 0.05) and PFI (all between r \(\leq-0.410\) and \(-0.246\) and \(p\) < 0.05) in all children. However, the associations are stronger for FMR, which, unlike WC and BMI, takes muscle mass into consideration. Furthermore, Figure 2 shows that FMR is more strongly correlated with MC (\(r=-0.390\), \(p\) < 0.01) and PFI (r = \(-0.577\), \(p\) < 0.01) in boys than in girls. Therefore, the correlation between FMR and MC and PF is modulated by sex. According to the regression analyses, after adjusting for sex and age, FMR is independently associated with MC and PFI, explaining 15,8% (\(p\) = 0.01) and 26,5% (\(p\) < 0.01) of its variability, respectively (Table 3A). In the same way, WC is independently associated with MC and PFI, explaining 15.0% (\(p\) = 0.01) and 25.6% (\(p\) < 0.01) of its variability, respectively (Table 3B). Finally, BMI is independently associated with MC and PFI, explaining 13.9% (\(p\) = 0.03) and 28.4% (\(p\) < 0.01) of its variability, respectively (Table 3C). Furthermore, in three models, sex is an independent variable for MC (\(p\) < 0.05) and PFI (\(p\) < 0.01). Interestingly, \begin{table}
\begin{tabular}{l c c c c} \hline  & **Total (n = 164)** & **Boys (n = 81)** & **Girls (n = 83)** & \(p\)**-Value** \\ \hline Age (years) & 7.41 \(\pm\) 0.32 & 7.41 \(\pm\) 0.32 & 7.41 \(\pm\) 0.33 & 0.95 \\ \hline ANTHROPOMETRICS & & & & \\ \hline Fat mass (Kg) & 5.63 \(\pm\) 2.70 & 5.19 \(\pm\) 2.27 & 6.07 \(\pm\) 3.01 & **0.04** \\ \hline Muscle mass (kg) & 16.71 \(\pm\) 2.57 & 18.67 \(\pm\) 1.63 & 14.78 \(\pm\) 1.72 & **<0.01** \\ \hline FMR (Kg) & 0.34 \(\pm\) 0.16 & 0.27 \(\pm\) 0.11 & 0.40 \(\pm\) 0.17 & **<0.01** \\ \hline WC (cm) & 58.84 \(\pm\) 6.12 & 58.82 \(\pm\) 6.0 & 58.86 \(\pm\) 6.24 & 0.97 \\ \hline BMI\_SDS (Kg/m\({}^{2}\)) & \(-0.21\)\(\pm\) 0.84 & \(-0.23\)\(\pm\) 0.8 & \(-0.18\)\(\pm\) 0.88 & 0.06 \\ \hline MOTOR COMPETENCE & & & & \\ \hline MC (CAMSA points) & 14.58 \(\pm\) 4.18 & 15.91 \(\pm\) 4.35 & 13.29 \(\pm\) 3.59 & **<0.01** \\ \hline PHYSICAL FITNESS & & & & \\ \hline CRF (min) & 5.23 \(\pm\) 0.76 & 4.98 \(\pm\) 0.73 & 5.44 \(\pm\) 0.70 & **<0.01** \\ \hline UBMS (Kg) & 20.09 \(\pm\) 4.34 & 20.66 \(\pm\) 3.82 & 19.53 \(\pm\) 4.67 & 0.09 \\ \hline LBMS (m) & 95.53 \(\pm\) 16.60 &
\begin{tabular}{c} 100.48 \\ 17.46 \\ \end{tabular} & 90.72 \(\pm\) 14.23 & **<0.01** \\ \hline SP (min) & 25.17 \(\pm\) 2.58 & 24.27 \(\pm\) 2.39 & 26.03 \(\pm\) 2.47 & **<0.01** \\ \hline PFI (points) & \(-0.17\)\(\pm\) 2.74 & 0.97 \(\pm\) 2.25 & \(-1.26\)\(\pm\) 2.46 & **<0.01** \\ \hline \end{tabular} Data are represented as mean \(\pm\) SD. Differences between sex were examined by Student’s \(t\)-test. The significance level (\(p\)-value) is set at 0.05, and significant values are marked in bold. Abbreviations: FMR = fat-to-muscle ratio; WC = waist circumference; BMI_SDS: body mass index standardized; MC = motor competence; CRF = cardiorespiratory fitness; UBMS = upper-body muscular strength; LBMS= lower-body muscular strength; SP = speed; PFI = physical fitness index.  
\end{table} 
Table 2: [PERSON]’s correlation between body composition (FMR, WC and BMI), motor competence and physical fitness index in all children. \begin{table}
\begin{tabular}{l c c c} \hline  & **FMR** & **WC** & **BMI** \\ \hline Motor competence (CAMSA points) & \(\mathbf{-0.333\ \text{\text{\text{\text{\text{\text{\text{\text{\text{\textascionly FMR is independently and negatively associated with MC and PFI, explaining 12.6% (\(p\) < 0.01) and 20.9% (\(p\) < 0.01) of its variance, respectively (Table 3D). Linear regression analysis was used. \(p\)-values are from the linear regression analysis using the stepwise method. The significance level is set at 0.05, and significant values are marked in bold.