(37) THE EFFECTS OF PLYOMETRIC TRAINING VOLUME ON JUMP PERFORMANCE USING 6-WEEK PLYOMETRIC TRAINING PROGRAM

Purpose: The purpose of this study was to compare the impact of plyometric training (PT) volume during a 6-week PT program on changes in horizontal and vertical lower body power by assessing changes in broad jump (BJ), squat jump (SJ), countermovement jump (CMJ), and approach jump (AJ) performance in physically active individuals (PAI). Methods: Twelve physically active males, with no formal PT experience, were randomly assigned to a moderate-volume (n = 6; age: 24.0 ± 6.0 yrs; body mass 77.7 ± 17.0 kg; height 1.7 ± 0.1 m) or high-volume (n = 6; age: 21.3 ± 2.5 yrs; body mass 78.5 ± 8.1 kg; height 1.8 ± 0.1 m) PT group. Before training, subjects underwent a 2-week accommodation period to familiarize themselves with the training protocol. Subjects then completed pre-testing which included the BJ, SJ, CMJ, and AJ. Trials continued until no further increase in jump height was observed. The highest jump height from each jump type was used for analyses. After pre-testing, subjects participated in a 6-week PT program (2 sessions per week). Both training groups completed the same PT program, however, the moderate-volume group completed 90-140 foot contacts per session, while the high-volume group completed 115-180 foot contacts per session, representing a 30% increase in volume. Post-testing was conducted following the completion of the PT program, using the same procedures as pre-testing. Four separate 2 (Volume: moderate and high) x 2 (Time: Pre-test and Post-test) repeated measures ANOVA were used to examine changes in the BJ, SJ, CMJ, and AJ jump height values. Effect sizes were reported as partial eta-squared ηp² for the ANOVAs and an alpha value of p ≤ 0.05 was considered statistically significant. Results: The results of the present study indicated that there were no significant 2-way interactions for the BJ, SJ, CMJ, and AJ, but, there were significant main effects for time (BJ: p < 0.001, ηp² = 0.69; CMJ: p = 0.020, ηp² = 0.43; AJ: p < 0.001, ηp² = 0.85). The main effect for time (collapsed across volume) indicated that the post-test values for the BJ, CMJ, and AJ (BJ = 248.2 ± 12.8 cm; CMJ = 65.5 ± 8.7 cm; AJ = 73.0 ± 8.5 cm) were greater than the pre-test values (BJ = 235.7 ± 14.9 cm; CMJ = 63.9 ± 8.3 cm; AJ = 68.1 ± 8.6 cm). In addition, there was a significant main effect for volume for the BJ (p = 0.050, ηp² = 0.33) where the high-volume group (collapsed across time) was greater (51.02 ± 6.46 cm) than the moderate-volume group (232.82 ± 6.65 cm). Conclusions: The results of this study indicated that both moderate-volume (1460 total foot contacts) and high-volume (1850 total foot contacts) PT for 6-weeks improved horizontal (BJ) and vertical (CMJ, AJ) lower body power in PAI. However, no changes in SJ performance were observed post-training for either group. These findings suggested that higher PT volume (as measured by foot contacts) does not lead to greater improvements in jumping performance, raising questions about the necessity of higher training volumes. Practical Applications: Coaches and trainers designing PT programs may benefit from individualizing training volume based on factors such as training status, training history, and injury status to optimize performance and minimize the risk of injury. Acknowledgements: None