# Effects of Post-Activation Performance Enhancement on Jump Performance in Elite Volleyball Players
## 3 Results  
According to analysis of the mean data for all volleyball players, the CA used in this study was not effective to induce an increase in jump height. No significant effects between conditions in time changes (baseline vs. post measurements) and interactions between analyzed factors were observed for either CMJ or SJ (Table 1). Taking into consideration mean values only for participants who positively responded to the CA, significant interactions between factors were noted for all measured variables. Post hoc analysis indicated significant time changes in all parameters only in association with the PAPE condition, both for SJ and CMJ; the control condition resulted in no significant change in baseline vs. post measurement. A larger effect size was observed for SJ than CMJ. Individual analysis showed that more participants positively responded to a CA in SJ (8 of 11; 73%) than CMJ (6 of 12; 50%) (Table 2). According to analysis of mean values for non-responders, there were no statistically significant differences between conditions, time change and interactions in any parameter of CMJ or SJ (Table 3). \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & & & & **CMJ** & & & \\ \hline \multirow{2}{*}{**Variable**} & \multirow{2}{*}{**Condition**} & \multirow{2}{*}{**Baseline**} & \multirow{2}{*}{**Post**} & \multirow{2}{*}{**Effect: Condition F(p)**} & \multirow{2}{*}{**Effect: Time F(p)**} & \multirow{2}{*}{**Interaction F(p)**} & **P: Post Hoc Pre-Post ([PERSON]’s d)** \\ \cline{3-8}  & & & & & & & **NS** \\ \hline \multirow{2}{*}{JH (cm)} & CNTR & 45.1 \(\pm\) 6.2 & 44.7 \(\pm\) 6.4 & \multirow{2}{*}{0.024 (0.88)} & \multirow{2}{*}{0.118 (0.73)} & \multirow{2}{*}{1.62 (0.21)} & NS \\ \cline{2-8}  & PAPE & 44.9 \(\pm\) 4.3 & 45.3 \(\pm\) 4.6 & & & & NS \\ \hline \multirow{2}{*}{FT (s)} & CNTR & 0.605 \(\pm\) 0.040 & 0.602 \(\pm\) 0.041 & \multirow{2}{*}{0.04 (0.84)} & \multirow{2}{*}{0.10 (0.75)} & NS \\ \cline{2-8}  & PAPE & 0.604 \(\pm\) 0.028 & 0.609 \(\pm\) 0.03 & & & NS \\ \hline \multirow{2}{*}{E (J)} & CNTR & 396.6 \(\pm\) 63.4 & 392.8 \(\pm\) 61.1 & \multirow{2}{*}{0.02 (0.88)} & \multirow{2}{*}{0.01 (0.92)} & \multirow{2}{*}{1.4 (0.24)} & NS \\ \cline{2-8}  & PAPE & 396.1 \(\pm\) 59.2 & 400.6 \(\pm\) 60.6 & & & NS \\ \hline \multirow{2}{*}{AP (W)} & CNTR & 2082.6 \(\pm\) 350.7 & 2065.8 \(\pm\) 334.7 & \multirow{2}{*}{0.01 (0.91)} & \multirow{2}{*}{0.11 (0.73)} & \multirow{2}{*}{1.62 (0.21)} & NS \\ \cline{2-8}  & PAPE & 2074.5 \(\pm\) 330.9 & 2103.7 \(\pm\) 340.2 & & & NS \\ \hline \multirow{2}{*}{RAP (W/kg)} & CNTR & 23.2 \(\pm\) 3.1 & 23 \(\pm\) 3.1 & \multirow{2}{*}{0.01 (0.92)} & \multirow{2}{*}{0.16 (0.69)} & \multirow{2}{*}{1.40 (0.24)} & NS \\ \cline{2-8}  & PAPE & 23 \(\pm\) 2.2 & 23.4 \(\pm\) 2.4 & & & NS \\ \hline \multirow{2}{*}{PP (W)} & CNTR & 5987.1 \(\pm\) 664.8 & 5957 \(\pm\) 635.1 & \multirow{2}{*}{0.01 (0.91)} & \multirow{2}{*}{0.12 (0.73)} & \multirow{2}{*}{1.62 (0.21)} & NS \\ \cline{2-8}  & PAPE & 5972.7 \(\pm\) 645.1 & 6025.1 \(\pm\) 659.8 & & & NS \\ \hline \multirow{2}{*}{RPP (W/kg)} & CNTR & 66.8 \(\pm\) 5.6 & 66.5 \(\pm\) 5.8 & \multirow{2}{*}{0.00 (0.98)} & \multirow{2}{*}{0.26 (0.61)} & \multirow{2}{*}{1.02 (0.32)} & NS \\ \cline{2-8}  & PAPE & 66.5 \(\pm\) 3.6 & 67.1 \(\pm\) 3.8 & & & NS \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Results of jumping tests for all participants at the baseline and after CA (presented as mean \(\pm\) SD).