STARTERS VERSUS NON-STARTERS: COUNTERMOVEMENT JUMP DERIVED NEUROMUSCULAR PERFORMANCE IN FEMALE COLLEGIATE VOLLEYBALL PLAYERS

Several studies from our laboratory demonstrated that NCAA Division III soccer players underperform anaerobically at the beginning of the playing season. Further examination of the data shows a large variability in performance measures between players. Such data has not been examined in NCAA Division III women's volleyball players. PURPOSE: This study aimed to utilize countermovement jump (CMJ) to provide insight into neuromuscular function and to compare starters and non-starters' performance. METHODS: Seventeen NCAA Division III women's volleyball team members (mean ± SD; age = 19.0 ± 0.4 years) volunteered to participate in this study. CMJ neuromuscular performance testing included jump height, peak eccentric and concentric force, peak eccentric and concentric power, and eccentric and concentric impulse. All performance testing occurred before the start of the regular season. The athletes were divided into starters (S) and non-starters (NS). RESULTS: Participants height (S: 1.73 ± 0.84; NS: 1.68 ± 0.73 m), weight (S: 71.31 ± 16.84; NS: 70.40 ± 9.65 kg), BMI (S: 23.85 ± 5.80; NS: 24.91 ± 3.59 kg·m2), CMJ height (S: 28.28 ± 5.36; NS: 27.10 ± 5.24 cm), peak eccentric force (S: 21.98 ± 2.32; NS: 22.50 ± 2.10 N × kg-1) peak concentric force (S: 22.12 ± 2.01; NS: 22.43 ± 3.25 N × kg-1), peak eccentric power (S: 15.61 ± 4.57; NS: 15.54 ± 4.12 W × kg-1) peak concentric power (S: 44.36 ± 5.46; NS: 43.17 ± 7.04 W × kg-1), eccentric impulse (S: 204.36 ± 71.67; NS: 201.05 ± 37.47 Ns) and concentric impulse (S: 367.74 ± 92.30; NS: 371.66 ± 63.50 Ns) were not significantly different (p > 0.05) between S and NS, and displayed medium, medium, small, small, trivial, trivial, trivial, trivial, small and small effect sizes (d), respectively, and between the groups. CONCLUSIONS: The study's results suggest that differentiating between starters and non-starters is not attributed to jump performance, but more likely to other factors such as sport specific skill, communication, and teamwork.