## 2 Methods
### Procedures  
Observational and Validated Data Collection  
We gathered data through direct systematic observations during the tournament group stage. The observed variables are detailed in Table 1 and Figure 1, following [PERSON] et al. [4], who codified variable recommendations. Two volleyball experts, each with a decade of technical experience in volleyball and specialized training in performance analysis, conducted observations. They used standardized and validated tools to accurately code each observed motor action to ensure reliable data collection. To minimize observational bias and ensure optimal game coverage, observers were strategically placed in stands on opposite sides of the court, six meters above the court level. This height was determined through extensive preliminary testing, which proved ideal for capturing both individual player actions and the overall team dynamics. This strategic placement, combined with an unobstructed view of the court, allowed for the complete, interference-free observation of all serves and subsequent gameplay actions. In addition to direct observations, physical data on each player's attack reach were collected throughout the tournament. To complement live observations and enable more detailed post-game analysis, we implemented a high-quality recording system. Each match \begin{table}
\begin{tabular}{c c} \hline
**Variables Study** & **Description Variables** \\ \hline Serving Technique & Powerful Jump Serve: A serve executed overhead, a spin power serve. \\ Floating Jump Serve: A serve delivered floating, without spin, over the head. \\ \hline \multirow{4}{*}{Serve Location} & Zone 1: Serve executed from a three-meter-wide area along the right sideline, \\  & behind the baseline. \\  & Zone 6: Serve from the center, three meters from the sideline, behind the baseline. \\  & Zone 5: Serve from a three-meter-wide area along the left sideline, behind \\  & the baseline. \\ \hline \multirow{4}{*}{Destination of Serve} & Zone 1: Reception inside a rectangle, located in the back of the court, on the right side of the court, 3 m from the back line and 4.5 m from the right sideline, 4.5 m from zone 6, and 3 m from zone 2. \\  & Zone 2: Reception inside a rectangle, located in the front area of the court, on the right side of the court, corresponds to 3 m from zone 1, 4.5 m from the right sideline, 3 m from the center line, and 4.5 m from zone 3. \\  & Zone 3: Reception inside a rectangle, located in the front area of the court, at the center of the court, corresponds to 3 m from zone 6 and 4.5 m from zone 2, 3 m from the center line, and 4.5 m from zone 4. \\  & Zone 4: Reception inside a rectangle, located in the front area of the court, on the left side of the court, corresponds to 3 m from zone 5, 4.5 m from zone 3, 3 m from the center line, and 4.5 m from the left sideline. \\  & Zone 5: Reception inside a rectangle, located at the back of the court, on the left side of the court, corresponds to 3 m from the baseline, 4.5 m from zone 6, 3 m from zone 4, and 4.5 m from the left sideline. \\  & Zone 6: Reception inside a rectangle, located at the back of the court, at the center of the court, corresponds to 3 m from the baseline, 4.5 m from zone 1, 3 m from zone 3, and 4.5 m from zone 5. \\ \hline \multirow{4}{*}{Result of Serve} & Inside the System: Reception directs the ball within the attacking zone. \\  & Outside the System: Reception directs the ball outside the attacking zone. \\  & Direct Point: Serve scores a point directly. \\ \hline Serving Error & Occurs when the serve fails to land within the opponent’s court or goes out \\  & of bounds. \\ \hline \end{tabular}
\end{table} 
Table 1: Codes for variables of female volleyball players. was recorded using Canon EOS 80D cameras (Canon Inc., Tokyo, Japan), which are known for their high image quality and reliability in sports.