(4) DROP LANDING AS A NEUROMUSCULAR FATIGUE ASSESSMENT: A SUBMAXIMAL ALTERNATIVE TO TRADITIONAL MONITORING METHODS

Purpose: The purpose of this study was to investigate whether drop landing metrics (i.e., fall height, landing phase duration, and landing performance index) can serve as reliable indicators of neuromuscular fatigue in volleyball players following a fatiguing training session. Methods: Fourteen elite male volleyball players (age: 29.18 ± 6.24 years; height: 1.95 ± 0.08 m; body mass: 95.17 ± 7.80 kg) participated in this study. On Day 1, athletes performed three countermovement jumps (CMJ) to determine their maximal jump height, which was used to establish individualized drop landing heights. On Day 2, athletes completed six drop landings from three different box heights (70%, 85%, and 100% of CMJ max height; two trials per height). Following this pre-training assessment, athletes participated in an 82.48-minute volleyball training session. Athletes repeated drop landings post-training. Test-retest reliability was assessed using intraclass correlation coefficients (ICC 3,1) with absolute agreement and coefficient of variation (CV%). Paired samples t-tests compared pre- and post-training drop landing metrics, and Cohen’s d effect sizes were calculated. The level of statistical significance was set at p < 0.05. Results: Test-retest reliability demonstrated good to excellent reliability across all drop landing metrics (ICC = 0.71–0.98, 95% CI; CV < 6%). Pre- and post-training comparisons (Table 1) revealed a significant decrease in fall height at 70% (p = 0.027, d = 0.13) and 100% (p = 0.003, d = 0.33) drop heights. Landing phase duration significantly increased at 100% drop height (p = 0.015, d = 0.75), while landing performance index significantly decreased at 85% (p = 0.019, d = 0.40) and 100% (p = 0.002, d = 0.61) drop heights. Conclusions: The findings indicate that drop landing metrics are sensitive to neuromuscular fatigue following an elite volleyball training session, with fall height, landing phase duration, and landing performance index demonstrating significant changes at specific drop heights. The observed increase in landing phase duration at 100% drop height suggests that athletes adopt a more compliant landing strategy under fatigue, likely to reduce mechanical stress. Additionally, the observed changes in landing performance index highlight the importance of evaluating landing efficiency rather than relying solely on single-component metrics such as fall height. Practical Applications: Drop landing tests may provide a submaximal alternative for assessing neuromuscular fatigue, offering reliable insights into an athlete’s readiness. Strength and conditioning practitioners can use drop landing assessments to monitor fatigue trends over time, particularly in elite sports environments where motivation and load management play key roles in performance optimization. Future research should explore how individual movement strategies influence landing adaptations and whether drop landing assessments can be effectively integrated into routine fatigue monitoring protocols in high-performance settings. Acknowledgements: None.