# Biomechanical Assessment of Throwing Gesture and Performance in Female Water-Polo Players
## 3 Results  
Results are reported for the three types of shots. The median and interquartile range (IQR) values of each biomechanical parameter are reported in Table 1, both before and after the training program. In PFS, the shoulder angle increased by 7\({}^{\circ}\) after the training (\(p\)-value = 0.003), while the maximum velocity \(Vmax_{y}\) resulted lower (14.7 m/s before the training, 13.9 m/s after the training, \(p\)-value = 0.005). In the PSS shot, the precision score shows an increase of 2 scores after the training (\(p\)-value = 0.05). No statistical differences were obtained in the comparison of elbow angles and power results. The Pre- and Post-training results are also graphically compared through boxplots. Figure 4 shows the shoulder (A) and elbow (B) angles at the throwing phase, while Figure 5 depicts the maximum velocity (A), the power estimated at the throwing phase (B), and the precision score (C). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Parameters** & \multicolumn{2}{c}{**PS**} & \multicolumn{2}{c}{**PSS**} & \multicolumn{2}{c}{**PFS**} \\ \hline  & _Pre_ & _Post_ & _Pre_ & _Post_ & _Pre_ & _Post_ \\ \hline Shoulder angle (\({}^{\circ}\)) & 59.5 (10.9) & 68.2 (13.3) & 62.3 (16.6) & 64.7 (10.9) & 56.7 (12.1) & 63.9 (12.1) \\ \(p\)-value & 0.12 & & 0.61 & & 0.003 & \\ Ebow angle (\({}^{\circ}\)) & 32.6 (12.2) & & 37.1 (5.9) & 33.9 (18.5) & 37.4 (21.6) & 26.1 (11.8) & 32.1 (16.2) \\ \(p\)-value & 0.22 & & 0.13 & & 0.17 & 0.17 \\ Vmax\({}_{y}\) (m/s) & 12.9 (0.7) & & 12.7 (1.4) & 13.2 (2.7) & 13.5 (1.5) & 14.7 (1.8) & 13.9 (0.8) \\ \(p\)-value & 0.08 & & 0.08 & & 0.005 & \\ Throwing power (W) & 134 (91) & & 147 (140) & 143 (141) & 166 (109) & 148 (51) & 131 (112) \\ \(p\)-value & 0.97 & & 0.77 & & 0.77 & 0.77 & \\ Precision score & 11.0 (2.8) & & 13.0 (5.3) & 9.0 (4.8) & 11.0 (3.0) & 11.0 (4.0) & 11.0 (1.0) \\ \(p\)-value & & 0.72 & & 0.05 & & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Comparison of the biomechanical parameters. Median and interquartile range (IQR) are reported for each parameter, before (_Pre_) and after (_Post_) the training, as well as the \(p\)-values obtained from the _Pre_–_Post_ comparison. Statistically significant \(p\)-values are highlighted in bold. PS: penalty shot; PSS: passing-spontaneous shot; PFS: passing-feint shot. Figure 4: Boxplots showing the median and IQR of the shoulder (**A**) and elbow (**B**) angles calculated before and after the training program. PS: penalty shot; PSS: passing-spontaneous shot; PFS: passing-feint shot. Statistically significant differences between the _Pre_ and _Post_ conditions are highlighted with asterisks (** represents a \(p\)-value \(<\) 0.01). Figure 6 shows the regression analysis between the shoulder and elbow angles and between each of these angles and the maximum velocity (along the \(y\)-axis), before and after training. The R values of correlation are reported in Table 2. The analysis of the Shoulder-Elbow kinematic correlation revealed a positive R value (R = 0.47 before training; R = 0.51 after the training), while negative R values resulted in the correlation between kinematic angles and maximum velocity. In particular, a moderate correlation was found between the elbow angle and the velocity (R = \(-\)0.56, both before and after the training), while a weak correlation was found between the shoulder angle and the velocity (R = \(-\)0.36 before the training, R = \(-\)0.24 after the training). No statistical differences were found between regression lines before and after the training program. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Correlation Coefficient R**} \\ \hline Shoulder angle–Elbow angle & Shoulder angle–Vmax\({}_{y}\) & \multicolumn{2}{c}{Elbow angle–Vmax\({}_{y}\)} \\ _Pre_ & _Post_ & _Pre_ & _Post_ & _Pre_ & _Post_ \\
0.47 & 0.51 & \(-\)0.36 & \(-\)0.24 & \(-\)0.56 & \(-\)0.55 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Spearman correlation coefficient R among joint kinematic angles and velocity.