## 4 Discussion
### Speed and Strength  
Our study highlights significant relationships between strength parameters and performance outcomes in the assessed exercises--SQs, BPs, and DLs--specifically regarding their impact on maximum RP. These findings are crucial for optimizing volleyball training programs that emphasize both power and speed development. The SQ results demonstrated a notable correlation between minimum lifted weight and RP during the 10 m sprint test. These results suggest that athletes with increased strength relative to their body weight were likely to develop greater power in jumping and sprinting. Previousresearch supports these results. [PERSON] et al. [38] proved that lower body strength is important in sports requiring fast acceleration and vertical jumps. This insight is valuable for designing drills that improve not only strength but also explosive power, important for blocking and attacking, whereas the current statement is reinforced by the maximum RF (13.55 N/kg) monitored in our paper, which was related to the 10 m sprint test result. Therefore, incorporating multi-directional glyometrics, proprioceptive exercises, and sport-specific drills alongside strength training can mitigate potential declines in coordination while maintaining agility improvements. This balanced approach ensures that strength gains translate effectively to dynamic performance. Although the relationship between SQ performance and the best lap time was not significant (\(p>0.05\)), the median time of 2.10 s suggests that lower body strength still contributes to speed. This aligns with findings from studies emphasizing the importance of lower body strength in improving the sprint performance and agility of volleyball players [39]. However, targeted strength training, when carefully programmed, tends to enhance agility by improving neuromuscular efficiency and force application during rapid directional changes. Yet excessive emphasis on hypertrophy or unilateral strength development may disrupt coordination, particularly in complex volleyball actions. During the BPs, the minimum lifted weight showed a significant correlation with power (\(p=0.0413\), \(r=0.3283\)), indicating that upper body strength is linked to performance, particularly in movements requiring pushing force. This is essential for effective serving and hitting in volleyball, which, in practice, means that volleyball players can improve their hitting and serving power by focusing on upper body strength in their training programs. However, the correlations with best lap times were less important, particularly with a negative r value (\(-0.043\)) in maximum lifted weight, suggesting that while upper body strength is important, it may not be as critical for speed compared to lower body strength. Exploring the neurophysiological effects of strength training may reveal how alterations in motor unit recruitment or changes in muscle stiffness affect coordination. Understanding these mechanisms can guide training interventions to maximize both strength and coordination. Further on, these findings are consistent with previous studies in the literature that suggests upper body strength contributes to overall performance [40] but may have a less pronounced effect on speed performance in team sports, unlike sports that use upper body muscles to obtain speed [41]. Due to the DL performance, we obtained significant correlations between both minimum lifted weight (\(p=0.0001\), \(r=0.559\)), maximum lifted weight (\(p=0.0001\), \(r=0.468\)), and RP. These results highlight the importance of posterior chain strength for overall performance in volleyball, aligning with research that indicates the DL effectively develops strength in key muscle groups [42]. However, the relationships with best lap times were less pronounced, particularly with maximum power, showing a lack of correlation (\(p=0.907\), \(r=-0.017\)). This result suggests that while the DLs contribute to strength development, their direct impact on speed performance may be limited.