Examination of mechanical force-velocity profiles according to maturation periods in volleyball players and investigation of the relationship with spike jump performance

This study aimed to compare vertical mechanical force-velocity (F-V) profiles of volleyball players based on their maturity status and investigate the relationship between F-V profile parameters and spike jump performance. The research included 42 volleyball players who had received a minimum of 1 year of volleyball training. A cross-sectional research design was employed, and participants' anthropometric measurements along with biological maturity status were calculated using the Mirwald method. Biological maturity statuses were determined according to the "peak height velocity" (PHV) (pre-PHV n=9, during PHV n=14, post-PHV n=19). The mechanical F-V profile was determined using Samozino's method through unloaded and loaded countermovement jumps. ANOVA was used to detect intergroup differences, with Bonferroni test used for pairwise comparisons. Correlation analysis was conducted to examine the relationships between vertical mechanical F-V profile parameters and spike jump height. Significant differences were observed between vertical mechanical F-V profile parameters (force: F0 (N), F0 (N/kg); velocity: V0 (m/s); power: Pmax (W), Pmax (W/kg), force-velocity imbalance: FVimb) and spike jump height, with significant variations in F0 (N), F0 (N/kg), V0 (m/s), Pmax (W/kg), FVimb, and spike jump height values (p<0.05, η2=0.19-0.69). Weak correlations were found between spike jump height and F0 (N), F0 (N/kg), and Pmax (W) parameters (p<0.05, r=0.31-0.39). In conclusion, the results of this study demonstrate that the vertical mechanical F-V profile varies based on the maturity status. Biologically more mature volleyball players possess higher force parameters and lower velocity values. Moreover, weak relationships were identified between vertical mechanical F-V profile parameters and spike jump height. Keywords: Force, Velocity, Force-velocity profile, maturity, countermovement jump, spike jump.