## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline  & & & & & & & & & & \\ \multicolumn{1}{c}{} & & & & & & & & & & \\ \multicolumn{1}{c}{} & & & & & & & & & & \\ \hline \multirow{6}{*}{Active (\(\mathrm{\SIUnitSymbolMicro}\)A)} & **BFlh** & 29.41 \(\pm\) 9.92 & 30.56 \(\pm\) 14.16 & 28.79 \(\pm\) 11.11 & 29.02 \(\pm\) 16.47 & 0.628 & 0.019 & 0.798 & 0.005 & 0.592 & 0.023 \\  & **BFlh** & 47.32 \(\pm\) 10.33 & 51.55 \(\pm\) 18.05 & 58.84 \(\pm\) 16.71 & 51.55 \(\pm\) 18.38 & 0.034 & 0.348 & 0.684 & 0.016 & 0.068 & 0.272 \\  & **SM** & 32.82 \(\pm\) 9.37 & 38.86 \(\pm\) 12.21 & 33.07 \(\pm\) 9.14 & 36.36 \(\pm\) 11.93 & 0.635 & 0.021 & 0.251 & 0.118 & 0.920 & 0.001 \\  & **ST** & 61.52 \(\pm\) 18.91 & 60.53 \(\pm\) 13.41 & 60.67 \(\pm\) 17.87 & 66.72 \(\pm\) 14.24 & 0.120 & 0.189 & 0.636 & 0.019 & 0.036 & 0.318 \\ \multirow{2}{*}{Ratio} & **BFlh/ST** & 0.51 \(\pm\) 0.18 & 0.54 \(\pm\) 0.20 & 0.49 \(\pm\) 0.17 & 0.46 \(\pm\) 0.20 & 0.329 & 0.079 & 0.922 & 0.001 & 0.160 & 0.157 \\ \hline
**Peak Torque (\(\mathrm{\SIUnitSymbolMicro}\)A)** & 139.35 \(\pm\) 44.69 & 137.63 \(\pm\) 38.93 & 131.18 \(\pm\) 38.15 & 130.39 \(\pm\) 36.42 & 0.010 & 0.415 & 0.739 & 0.009 & 0.679 & 0.014 \\ RTD 0-50 (N\(\cdot\)m/s) & 480.64 \(\pm\) 23.37 & 394.91 \(\pm\) 223.23 & 513.21 \(\pm\) 240.57 & 450.53 \(\pm\) 194.45 & 0.028 & 0.005 & 0.465 & 0.306 & 0.080 \\ RTD 50-100 (N\(\cdot\)m/s) & 770.31 \(\pm\) 268.99 & 725.57 \(\pm\) 288.79 & 745.66 \(\pm\) 245.47 & 724.34 \(\pm\) 244.45 & 0.617 & 0.020 & 0.221 & 0.113 & 0.326 & 0.074 \\ RTD 150-200 (N\(\cdot\)m/s) & 358.05 \(\pm\) 150.08 & 373.25 \(\pm\) 108.94 & 319.07 \(\pm\) 103.33 & 342.59 \(\pm\) 107.17 & 0.136 & 0.163 & 0.371 & 0.062 & 0.720 & 0.010 \\ \multirow{2}{*}{TU-RTDmas (s)} & & & & & & & & & & \\  & & & & & & & & & & \\ \multicolumn{1}{c}{} & & & & & & & & & & \\ \multicolumn{1}{c}{} & & & & & & & & & \\ \end{tabular} Abbreviations: BFlh, biceps femoris long head; BFlh, biceps femoris short head; SM, semimembransous; ST, semintendinosus; BFlh/ST ratio, biceps femoris long head ratio; RTD 0-50, rate torque development between 0-50 ms; RTD 50–100, rate torque development between 0-50 ms; RTD 50–100, rate torque development between 50–100 ms; RTD 150–200, rate torque development between 150–200 ms; TU-RTDmax, time until reach the maximum value of rate torque development (ms); \(p\), \(p\) value; \(\mathrm{m}_{p}^{2}\), \(\mathrm{m}_{p}\), \(\mathrm{t}\)s squared. Data are presented as mean \(\pm\) standard deviation.  
\end{table} 
Table 4: Acute effects of a sprint protocol in limbs with biceps femoris long head injury history (n = 14) vs. healthy contralateral limbs (n = 14) on the active shear modulus and neuromuscular parameters. pacted the sprint performance in players with previous his, which led to a non-significant difference between groups. Moreover, other previous studies reported no differences in the sprint performance between healthy controls players and players who had suffered from any lower-limb previous injury in either limb [37]. In addition, previous HSI has been shown to have no association with the change in the sprint performance throughout the off-season [38]. Therefore, all these studies support that evaluating players after 2-3 months of return to play after a HSI showed no differences between previously injured vs. healthy control players. Neuromuscular fatigue has been suggested to be a potential risk factor for muscle strain injury [2; 9; 39; 40], indicating that insufficient strength exercise could represent a risk factor to sustain a new HSI, or that insufficient rehabilitation after an HSI may increase the risk of re-injury. Contrary to our initial hypothesis, no significant differences were seen in all of the neuromuscular parameters when comparing the previously injured vs. healthy controls players, and between all HSI and contralateral limbs. Only a significant difference was seen in RTD 0-50 ms in the comparison of previously injured limbs on BFlh vs. contralateral limbs.