## 3 Results
### RSA Test  
After analyzing the entire 40 m sprint, no significant differences between the groups or interaction were found in the different variables of the RSA (Tables 3 and 4 and Figures 3 and 4). If the analysis is carried out considering the initial 20 m, the percentage difference between SplitTT and Ideal Split was different between 0-10 m and 0-20 m (F (1.17) = 5.87; \(p\) = 0.027; \(\eta^{2}\) = 0.257) without significant differences between the groups. Also, an interaction was found (F (1.17) = 5.76; \(p\) < 0.028; \(\eta^{2}\) = 0.253). The pairwise comparisons showed that the percentage difference between SplitTT and Ideal Split was not different between 0-10 m and 0-20 m in the control group, but it was lower in 0-20 m than in 0-10 m in the hamstring group (\(p\) = 0.006; ES = 0.51) (Figure 3). When the last two sprints were compared, %Diff1 vs5 was lower than %Diff1 vs6 (F (1.15) = 10.27; \(p\) = 0.006; \(\eta^{2}\) = 0.407) without a significant difference between the groups. An interaction effect was found (F (1.15) = 4.29; \(p\) = 0.05; \(\eta^{2}\)= 0.222). The pairwise comparisons showed that %Diff1 vs5 was similar to %Diff1 vs6 in the control group, but %Diff1 vs5 was lower compared to %Diff1 vs6 in the hamstring group (\(p\) = 0.005; ES = 0.54) (Table 3). The statistical power was calculated on the RSA variable \"Percentage difference between SplitTT and Ideal Split\" with the software G power (Version 3.1.9.7). It was calculated based on the ES of the partial eta-squared (np2) observed in this variable \"0.5819691\" (large), \begin{table}
\begin{tabular}{l l l l l l} \hline \hline  & & **Split 0-10 m** & **Split 0-20 m** & **Split 0-30 m** & **Split 0-40 m** \\ \hline SplitTT (s) & Control & 12.37 \(\pm\) 0.76 & 21.14 \(\pm\) 1.13 & 29.61 \(\pm\) 1.72 & 38.34 \(\pm\) 2.36 \\  & Hamstring & 12.16 \(\pm\) 0.83 & 20.7 \(\pm\) 1.12 & 28.9 \(\pm\) 1.45 & 36.6 \(\pm\) 2.86 \\ Ideal Split (s) & Control & 11.82 \(\pm\) 0.61 & 20.36 \(\pm\) 0.83 & 28.55 \(\pm\) 1.27 & 36.82 \(\pm\) 1.88 \\  & Hamstring & 11.29 \(\pm\) 1.33 & 19.65 \(\pm\) 1.47 & 27.72 \(\pm\) 1.56 & 35.39 \(\pm\) 2.27 \\ \hline \hline \end{tabular} Values presented as means \(\pm\) SD. SplitTT: Split Total Time, defined as the time spent to complete a specific distance during the six sprints; Ideal Split, defined as the SplitTT if all the splits were run as the best of them; Control: Subjects without previous hamstring injury; Hamstring: Subject with previous hamstring injury.  
\end{table} 
Table 4: SplitTT and Ideal Split from Split 0–10 m to Split 0–40 m of the RSA test. \begin{table}
\begin{tabular}{l l l l l l l l} \hline \hline  & & **Split 1** & **Split 2** & **Split 3** & **Split 4** & **Split 5** & **Split 6** \\ \hline \multirow{2}{*}{\(\text{Sprint}_{\text{TT}}\) 0–10 m (s)} & Control & 2.01 \(\pm\) 0.14 & 2.04 \(\pm\) 0.16 & 2.01 \(\pm\) 0.16 & 2.08 \(\pm\) 0.15 & 2.07 \(\pm\) 0.15 & 2.08 \(\pm\) 0.16 \\  & Hamstring & 2 \(\pm\) 0.13 & 2.07 \(\pm\) 0.15 & 2.04 \(\pm\) 0.15 & 2.11 \(\pm\) 0.14 & 2.07 \(\pm\) 0.16 & 2.05 \(\pm\) 0.11 \\ \multirow{2}{*}{\(\text{Sprint}_{\text{TT}}\) 0–20 m (s)} & Control & 3.04 \(\pm\) 0.19 & 3.48 \(\pm\) 0.2 & 3.45 \(\pm\) 0.24 & 3.54 \(\pm\) 0.23 & 3.54 \(\pm\) 0.22 & 3.58 \(\pm\) 0.23 \\  & Hamstring & 3.4 \(\pm\) 0.17 & 3.51 \(\pm\) 0.2 & 3.47 \(\pm\) 0.21 & 3.58 \(\pm\) 0.19 & 3.52 \(\pm\) 0.2 & 3.45 \(\pm\) 0.27 \\ \multirow{2}{*}{\(\text{Sprint}_{\text{TT}}\) 0–30 m (s)} & Control & 4.75 \(\pm\) 0.25 & 4.85 \(\pm\) 0.27 & 4.83 \(\pm\) 0.33 [FOOTNOTE:3]Footnote 3: Values presented as means \(\pm\) SD. SplitTT: Time to run a specific distance of the sprint; %Diff: Percentage difference between the first sprint and a specific sprint; Percentage difference between SplitTT and ideal sprint: percentage difference between the time to run a specific number of sprints and the time if these sprints were run as the best of them; Control: Subjects without previous hamstring injury; Hamstring: Subject with previous hamstring injury.  
\end{table}