## 3 Results
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Authors and Year** & **Sample Size (n)** & **Age (Views)** & **Country, Competition** & **Time of the SEA** & **Measuring Instruments** & **Evaluation Method** \\ \hline Hernández-Mosquaria & T = 158; DEF = 46; CEN = 58; & \(24.1+470\); \(25.3\pm 5.20\); & & & & \\ Mosquaria & DEL = 34; FOR = 20 & \(24.5\pm 4.90\); \(23.9\pm 3.90\); & CL. 1 st Division & 5 consecutive pre-SEAs & EST Sca 700, Kit Gaudio Pro & A-ISAK \\ et al. [33] & DEL = 34; FOR = 20 & \(22.8\pm 4.80\) & & & \"Mecosour\" & \\ \hline [PERSON] & T = 23; DEF = 6; CEN = 10; & \(24.0\pm 325,258\pm 3.25\); & & & & \\ et al. [34] & DEL = 5; FOR = 2 & \(23.0\pm 4.25\); \(25.0\pm 1.58\); & IT. Serie A & Half SEA & EST Sca 264, Measuring tape & A-SATA \\ \hline [PERSON] \& & T = 30; overall = 69; & & & & \\ [PERSON] [8] & lateral DEF = 5; CEN = 87; & \(25.4\pm 4.66\); \(<\) \(\gamma\) \(\gamma\) \(\gamma\) \(\gamma\) & EM. 1 st Division & 2 consecutive pre-SEAs & EST Tanta, Tanta BCA18 MA & BIA \\ \hline [PERSON] et al. [40] & T = 38; DEF = 12; CEN = 15; & \(25.9\pm 5.22\); \(27.5\pm 4.50\); & & & \\ DEL = 6; FOR = 5 & \(24.1\pm 4.90\); \(25.5\pm 5.90\); & PL. Ekstraklas & Full SEA & InBody 770 & BIA \\ \hline [PERSON] et al. [59] & T = 38; DEF = 12; CEN = 15; & \(24.13\pm 4.69\); \(25.5\pm 5.89\); & PL. Ekstraklas & Full SEA & InBody 770 & BIA \\  & DEL = 6; FOR = 5 & \(27.8\pm 7.19\) & & & & \\ \hline \end{tabular}
\end{table} 
Table 2: _Cont._ \begin{table}
\begin{tabular}{l c c c c c c c c} \hline \hline  & **Authors** & **G** & **M** & **95\% CI** & **Weight (\%)** & **M** & **95\% CI** & \(p\) \\ \hline \multicolumn{8}{c}{Age} \\ \hline Goalkeeper & [25–30,33,34,37,39,40,44,46,47] & 16 & 25.7 & 24.2; 27.3 & 17.0 & & & \\ Defender & [25–30,33–37,39,40,44–47] & 24 & 25.5 & 24.6; 26.3 & 29.1 & & & \\ Midfielder & [25–30,33–37,39,40,44–47] & 22 & 24.4 & 23.9; 24.9 & 27.7 & 24.9 & 24.4; 25.3 & 0.002 \\ Forward & [25–30,33–37,39,40,44–47] & 21 & 24.0 & 23.6; 24.4 & 26.2 & & & \\ \hline \multicolumn{8}{c}{Height} \\ \hline Goalkeeper & [23,25–34,37,39,40,43,44,46–48] & 22 & 186 & 184; 188 & 19.1 & & & \\ Defender & [23,25–40,43–48] & 34 & 181 & 179; 182 & 29.8 & 180 & 179; 181 & \textless{}0.001 \\ Middfielder & [23,25–40,43–48] & 30 & 176 & 175; 178 & 26.4 & & & \\ Forward & [23,25–40,43–48] & 29 & 179 & 178; 180 & 24.7 & & & \\ \hline \multicolumn{8}{c}{Weight} \\ \hline Goalkeeper & [23,25–34,37,39,40,43,44,46–48] & 22 & 82.4 & 80.2; 84.7 & 18.7 & & & \\ Defender & [23,25–41,43–48] & 35 & 77.4 & 75.8; 79.0 & 29.5 & & \\ Midfielder & [23,25–41,43–48] & 31 & 72.7 & 71.3; 74.1 & 27.4 & & & \\ Forward & [23,25–41,43–48] & 30 & 76.5 & 75.1; 77.9 & 24.4 & & & \\ \hline \multicolumn{8}{c}{Sum of 6 skinfolds} \\ \hline Goalkeeper & [25,30,33] & 3 & 58.9 & 58.3; 59.4 & 19.4 & & & \\ Defender & [24,25,30,33] & 4 & 54.9 & 43.0; 66.7 & 27.6 & 54.6 & 54.5; 57.7 & 0.038 \\ Midfielder & [24,25,30,33] & 4 & 53.9 & 46.2; 61.6 & 27.6 & 54.6 & 54.5; 57.7 & 0.038 \\ Forward & [24,25,30,33] & 4 & 52.5 & 41.0; 64.0 & 25.5 & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Meta-analysis by groups according to the playing position. G = groups; M = mean. Figure 2: Risk of bias summary: authors’ judgments broken down for each risk of bias criterion across all included studies.