## 3 Results  
The descriptive results of the FVP profile and the sprint performance across the surface conditions are shown in Table 1. The players showed large and significantly (\(p<\) 0.001) higher mean values for F0 (range ES: \(-\)3.02 to \(-\)1.61), V0 (range ES: \(-\)2.66 to \(-\)1.52), Pmax (range ES: \(-\)3.39 to \(-\)2.12), and RFpeak (range ES: \(-\)2.63 to \(-\)1.35) on the hard surface compared to the sand. Figure 1 shows the players' performance changes in F0, V0, Pmax, and RFpeak. Lower FVP profile values were obtained for the 20 m sprint on the sand. Likewise, large (ES from 2.29 to 3.99) and significantly (\(p<\) 0.001) lower 5 m and 20 m sprint times were achieved on the hard surface. No significant differences were observed between the two displacement surfaces for the DRF (Figure 2).  
As additional information, the 15 m sprint performance on the hard surface was large to very large, and significantly associated with the 10 m, 15 m, and 20 m sprint times on the sand. The distance covered in a 2 s sprint on sand was largely associated with a 4 s sprint (0.68, \(p\) < 0.01) on the hard surface, as well as with individual top speeds (0.74, \(p\) < 0.001). A significant and very large association (0.83, \(p\) < 0.001) was found between the sand and hard surface for the maximal distance achieved in 4 s. Finally, the top speeds achieved on both surface conditions were very largely associated (0.81, \(p\) < 0.001) with each other.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline  & **Hard Surface** & **Sand** & **\% \(\Delta\)** & **\(p\)-Value** & **\(r\) Correlation** &
\begin{tabular}{c} _p-Value_ \\ **(Correlation)** \\ \end{tabular} \\ \hline F0 (N\(\cdot\)kg\({}^{-1}\)) & 6.07 \(\pm\) 0.39 & 5.10 \(\pm\) 0.52 & \(-\)15.98 & \(<\)0.001 & \(-\)0.045 & 0.870 \\ V0 (m\(\cdot\)s\({}^{-1}\)) & 7.96 \(\pm\) 0.38 & 7.11 \(\pm\) 0.33 & \(-\)10.67 & \(<\)0.001 & 0.691 & 0.003 \\ Pmax (W\(\cdot\)kg\({}^{-1}\)) & 12.02 \(\pm\) 1.02 & 9.02 \(\pm\) 1.11 & \(-\)24.95 & \(<\)0.001 & 0.520 & 0.035 \\ DRF (\%) & \(-\)7.00 \(\pm\) 0.48 & \(-\)6.75 \(\pm\) 0.59 & \(-\)3.57 & NA & NA & NA \\ RFpeak (\%) & 0.44 \(\pm\) 0.02 & 0.38 \(\pm\) 0.03 & \(-\)13.63 & \(<\)0.001 & \(-\)0.254 & 0.342 \\
5 m time (s) & 1.52 \(\pm\) 0.05 & 1.68 \(\pm\) 0.79 & 10.52 & \(<\)0.001 & 0.130 & 0.633 \\
20 m time (s) & 3.09 \(\pm\) 0.94 & 3.41 \(\pm\) 0.14 & 10.35 & \(<\)0.001 & 0.753 & 0.003 \\ Top Speed (m\(\cdot\)s\({}^{-1}\)) & 7.58 \(\pm\) 0.34 & 6.67 \(\pm\) 0.42 & 7.80 & \(<\)0.001 & 0.807 & \(<\)0.001 \\ \hline \end{tabular} Data are shown as mean \(\pm\) SD. F0, theoretical maximal force; V0, theoretical maximal velocity; Pmax, maximal power; DRF, decrease in the ratio of horizontal-to-resultant force over acceleration; RFpeak, maximal ratio of horizontal-to-resultant force; N, Newtons; kg, Kilograms; m, meters; s, seconds; W, watts, \(\%\), percentage.  
\end{table}
Table 1: Main descriptive data and correlations between sprint mechanical FVP variables and sprint time displayed by female BH players on hard surface and sand.  
Figure 1: (**A**) Individual changes in V0. (**B**) Individual changes in F0. (**C**) Individual changes in Pmax. (**D**) Individual changes in RFpeak. All graphs show differences between hard surface and sand.