Assessing the Maximal Mechanical Capacities Through the Load-Velocity Relationship in Elite Versus Junior Male Volleyball Players

Background: Physical testing is crucial for athlete monitoring, talent identification, optimizing training, and tailoring programs to enhance game-performance in elite competitions. Hypothesis: Load-velocity (L-V) relationship variables discriminate between elite and junior volleyball players, correlate with volleyball-specific performance, and are generalizable across lower- and upper-body exercises. Study Design: Cross-sectional study. Level of Evidence: Level 3. Methods: A total of 9 elite and 11 junior volleyball players were assessed for the L-V relationship (load-axis intercept [L-0], velocity-axis intercept [v(0)], and area under the L-V relationship line [A(line)]) during the countermovement jump (CMJ) and bench press throw (BPT) exercises. Block and spike jump height, as well as standing and jumping spike speed were assessed 24 hours later. Results: Elite players presented greater magnitude in the L-V variables (P <= 0.03; effect size [ES] >= 1.06) and higher volleyball-specific performance (P <= 0.03; ES >= 1.09) than juniors (except for CMJ v(0) and A(line)). The L-V relationship variables were significantly associated with the block and spike jump height and jumping spike speed only in elite players (r >= 0.703 and P <= 0.04 in 11 out of 18 correlations). No significant associations were observed between CMJ and BPT for any L-V relationship variable (r <= 581; P >= 0.08, except for A(line) in junior players). Conclusion: The L-V relationship is a practical procedure to assess volleyball players' maximal mechanical capacities, which are associated with volleyball-specific performance in elite players. However, these data should not be used interchangeably between playing standards or exercises.