## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Relationships between Variables**} & \multicolumn{5}{c}{**R.W.**} & \multicolumn{2}{c}{**S.R.W.**} \\ \cline{3-8}  & & **Estimate** & **E.E.** & **C.R.** & \(\mathbf{p}\) & **EST** \\ \hline SC & \(\leftarrow\) & SD & \(-0.030\) & \(0.022\) & \(-1.360\) & \(0.174\) & \(-0.060\) \\ SC & \(\leftarrow\) & PA & \(0.001\) & \(0.000\) & \(5.317\) & *** & \(0.433\) \\ MD & \(\leftarrow\) & SD & \(0.120\) & \(0.144\) & \(0.835\) & \(0.404\) & \(0.038\) \\ PUVG & \(\leftarrow\) & SD & \(-0.070\) & \(0.020\) & \(-3.609\) & *** & \(-0.358\) \\ MD & \(\leftarrow\) & SC & \(0.055\) & \(0.295\) & \(0.186\) & \(0.853\) & \(0.009\) \\ PUVG & \(\leftarrow\) & SC & \(-0.166\) & \(0.040\) & \(-4.151\) & *** & \(-0.386\) \\ MD & \(\leftarrow\) & PA & \(-0.002\) & \(0.002\) & \(-0.926\) & \(0.354\) & \(-0.043\) \\ PUVG & \(\leftarrow\) & PA & \(0.001\) & \(0.000\) & \(2.778\) & ** & \(0.325\) \\ SD & \(\leftrightarrow\) & PA & \(-3.362\) & \(1.271\) & \(-2.644\) & ** & \(-0.319\) \\ \hline \hline \end{tabular} Note 3: Sleep Duration (hours per day) (SD); Self-Concept (SC); Physical Activity (minutes per day) (PA); Mediterranean Diet (MD); Problematic Use of videogames (PUVG). Note 2: Regression Weights (R.W.); Standardized Regression Weights (S.R.W.); Error Estimation (E.E.); Critical Ratio (C.R.); Estimations (EST). Note 3: Statistically significant relationship between variables at the level 0.001 (***); Statistically significant relationship between variables at the level 0.01 (***).  
\end{table} 
Table 4: Regression weights and standardized weights of the structural equation model for the females. development of self-concept, both in children and adolescents, is established. However, there is no direct relationship between both variables [31]. In this sense, according to [PERSON] et al. [35], the family exerts a greater influence on the development of self-concept during adolescence than the practice of physical activity. In this study, an association is found between the practice of physical activity and self-concept which may be due to the influence of factors such as body image, body mass index and level of physical condition [50] on the development of that variable in children. Regarding the inverse relationship found between physical activity and problematic use of videogames, it has been contrasted in other investigations such as those by [PERSON] et al. [51] and [PERSON] [52] where the effects that a high use of videogames has on the creation of sedentary lifestyles are corroborated. This can affect physical appearance and training of an inadequate self-concept due to a lack of the habit of physical activity [31]. On the contrary, a direct and bidirectional influence between engagement in physical activity and duration of sleep is found when their relationship is analyzed, as occurs in other studies such as those by [PERSON] et al. [53] and [PERSON] et al. [38]. Their conclusions highlight the benefits of engagement in physical activity on the adoption of healthy sleep and rest habits, which are necessary to promote better physical health and mental well-being, and therefore, to achieve an optimal psychological profile. Another result obtained in this research is that self-concept is directly related to adherence to a Mediterranean diet and inversely related to the problematic use of videogames. It should be pointed out that a direct association between self-concept and adherence to Mediterranean diet has also been found in previous studies such as that of [PERSON] et al. [11], where it is verified that the follow-up of the Mediterranean diet together with engagement in physical activity are conceived as factors of great relevance for the child's development of a positive vision of himself or herself. Self-vision or self-concept, in the case of children with a problematic use of videogames, will be negative, as demonstrated both in this research and in previous studies, for example, [PERSON] et al. [31], [PERSON] et al. [54], and [PERSON] et al. [12].