## 3 Results  
The descriptive data of the time results of the running and cycling repeated sprint test are presented in Table 1. The cycling sprint times of each player were constructed from the average sprint times in the running test. The mean values (\(\pm\)SD) for the physiological response and performance variable measurements recorded during the running and the cycling are summarised in Table 2. Significantly greater values for the PP, MP, and RPE were observed in the cycling (\(p<0.05\)), whereas the HRpeak and lactate responses were similar. For the fatigue index, a statistically significant difference was observed, and this difference was higher in the running test (\(p<0.05\)). Figure 2 displays the peak power output for each sprint interval (running) compared with the power output from cycling partitioned into six 5.37 s intervals. Regarding the estimated contribution of the energy systems and the energy expenditure (see Table 3), higher values were observed for the percentage and absolute contributions of the ATP-PCr system (\(p<0.01\)), energy demand (\(p<0.01\)), TEE (\(p<0.01\)), PCr_Breaks (\(p<0.01\)), and PCr_Epocfast (\(p<0.01\)) in the running test. However, no difference was \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Running Test (s)** & **Cycling Test (s)** \\ \hline \hline  & 4.98 \(\pm\) 0.140 & 5.37 \\  & 5.11 \(\pm\) 0.150 & 5.37 \\  & 5.28 \(\pm\) 0.163 & 5.37 \\  & 5.43 \(\pm\) 0.139 & 5.37 \\  & 5.64 \(\pm\) 0.151 & 5.37 \\  & 5.80 \(\pm\) 0.192 & 5.37 \\  & 5.37 \(\pm\) 0.312 & 5.37 \\  & 32.25 & 32.24 \\ \hline \hline \end{tabular} MST = mean sprint time, TST = total sprint time.  
\end{table} 
Table 1: Running and cycling sprints duration. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Variables**} & **Running** & **Cycling Test** & **Sprint Mode** & \multirow{2}{*}{\(p\)} & \multirow{2}{*}{\(\mathbf{\eta^{2}}\)} \\  & **Test** & & **Effect** & & \\ \hline Peak power (W) & 713.7 \(\pm\) 94.9 & 1012.9 \(\pm\) 132.9 & F = 107.388 & 0.000 & 0.634 \\ Mean power (W) & 578.3 \(\pm\) 72.1 & 876.1 \(\pm\) 105.8 & F = 173.157 & 0.001 & 0.736 \\ FI (\%) & 36.5 \(\pm\) 6.6 & 30.0 \(\pm\) 6.8 & F = 19.949 & 0.002 & 0.243 \\ Resting lactate & \multirow{2}{*}{0.7 \(\pm\) 0.2} & \multirow{2}{*}{0.8 \(\pm\) 0.3} & F = 0.259 & 0.162 & 0.003 \\ (mmol\(\cdot\)L\({}^{-1}\)) & & & & & \\ Maximal lactate & \multirow{2}{*}{15.4 \(\pm\) 1.6} & \multirow{2}{*}{15.1 \(\pm\) 1.5} & F = 0.560 & 0.133 & 0.251 \\ (mmol\(\cdot\)L\({}^{-1}\)) & & & & & \\ Lactate delta & \multirow{2}{*}{14.7 \(\pm\) 1.7} & \multirow{2}{*}{14.3 \(\pm\) 1.6} & F = 0.561 & 0.102 & 0.011 \\ (mmol\(\cdot\)L\({}^{-1}\)) & & & & & \\ HR peak (ppm) & 176.3 \(\pm\) 10.1 & 177 \(\pm\) 6.7 & F = 0.241 & 0.159 & 0.009 \\ RPE & 13.4 \(\pm\) 1.1 & 16.2 \(\pm\) 1.4 & F = 10.456 & 0.000 & 0.345 \\ \hline \hline \end{tabular} FI = fatigue index, HR = heart rate, RPE = rate of perceived exertion.  
\end{table} 
Table 2: Physiological and performance responses for the running and cycling test. Figure 2: Results of the power generated in each sprint of running and cycling. observed for the glycolytic and oxidative systems percentage and absolute contributions (Figure 3). Table 4 presents the coefficient of determination (\(r^{2}\)) values, detailing the relationships between different energy system contributions and performance variables across repeated sprint modalities in running and cycling. The results illustrate significant correlations for the ATP-PCr and glycolytic energy systems with their respective performance outputs in both modalities, highlighting their crucial roles in short-duration, high-intensity efforts. Specifically, the ATP-PCr system shows the strongest correlation (\(r^{2}\) = 0.58 for running and \(r^{2}\) = 0.46 for cycling with \(p\) < 0.01), underscoring its dominance in energy supply during these activities.