## 3 Results  
In Table 2, the descriptive and the differential analysis in relation to playing time was performed. The starting-up players presented higher values in total external load variables (\(Z=-6.37\) to \(-4.51\); \(p<0.001\); \(d=4.57\) to \(1.08\)), except in the Max Edi variable (\(Z=-0.15\); \(p=0.873\); \(d=0.06\)). Instead, the substitute players performed greater values in relative external load variables (\(Z=-6.24\) to \(-2.94\); \(p<0.001\); \(d=-1.69\) to \(-0.87\)), except in HDML/min (\(Z=-1.65\); \(p=0.099\); \(d=-0.55\)), DSL/min (\(Z=-0.03\); \(p=0.977\); \(d=-0.06\)), and PM/min (\(Z=-1.44\); \(p=0.148\); \(d=-0.61\)). Then, the correlational analysis between external load variables was shown in Figure 1 (starting-up players) and Figure 2 (substitute players). Differences in the correlations behavior in relation to playing time was found. In starting players, only direct relationships between variables were found. Nearly perfect results in within-variable correlations (total vs. relative) were shown. In between-variable correlations, very high relationships between PL, PM, HMLD, EE, and DSL, and trivial relationships between EDI and the rest of variables were found. Instead, in substitute players, an inverse correlation was found in within-variable correlations, except in DSL and HMLD. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Variables** & **Name and Acronym** & **Unit** & **Description** \\ \hline \hline \multirow{6}{*}{Metabolic Power (PM) (PM/min)} & \multirow{2}{*}{W/kg} & Product of speed (S) and energy cost of the activity (EC) derived from inclination and acceleration calculated by the following equation: PM = EC \(\times\) S \\ \cline{2-3}  & Metabolic Power/minute (PM/min) & \multirow{2}{*}{W/kg/min} & Estimate average Metabolic Power workload per min \\ \cline{2-3}  & High-Metabolic Load (HMLD) & & Distance travelled by a player when the metabolic power is \(>\)25.5 W/kg \\ \cline{2-3}  & High-Metabolic Load (HMLD/min) & & \\ \cline{2-3} Metabolic & \multirow{2}{*}{(m/min)} & Estimate average High Metabolic Load Distance per min \\ \cline{2-3}  & High-Metabolic Load Events (HMLE) & & \\ \cline{2-3}  & Energy Expenditure (EE) & (Kcl) & Energy of any body movement produced by skeletal muscles \\ \cline{2-3}  & Energy Expenditure/minute (EE/min) & \multirow{2}{*}{(Kcl/min)} & Average of Energy Expenditure per minute \\ \cline{2-3}  & Equivalent distance index (EDI max) & & \\ \cline{2-3}  & Equivalent distance index (\%) & & \\ \cline{2-3}  & (\%) & & \\ \cline{2-3}  & Equivalent distance index/minute (EDI/min) & (\%/min) & Average Equivalent Distance Index per minute \\ \hline \hline \multirow{6}{*}{Mechanical} & Dynamic Stress Load (DSL) & (n) & Total of the weighted impacts, based on accelerometer values over 2 g \\ \cline{2-3}  & Dynamic Stress Load/minute (DSL/min) & (n/min) & Average of Dynamic stress load per minute \\ \cline{1-1} \cline{2-3}  & Player Load (PL) & a.u. & Vector sum of device accelerations in the 3 orthogonal axes (vertical, anteroposterior, and lateral) \\ \cline{1-1} \cline{2-3}  & Player Load/minute (PL/min) & & \\ \hline \end{tabular}
\end{table} 
Table 1: Description of selected physical variables.