(55) THE EFFECTS OF SURFACE COMPOSITION DURING A 6-WEEK PLYOMETRIC TRAINING PROGRAM ON VERTICAL JUMP PERFORMANCE

Plyometric training programs may be performed on a hard surface or a soft surface to target specific training adaptations and enhance jump performance. However, it is unknown how surface compliance impacts jump performance. PURPOSE: The purpose of this study was to compare the effects of a 6-week plyometric training program on a hard surface or soft surface on squat jump (SJ), countermovement jump (CMJ), and approach jump (AJ) performance. METHODS: Eighteen physically active university students (males = 9, females = 9; age: 20.3 ± 1.7 yrs; height 170.0 ± 70.0 cm; body mass: 67.1 ± 7.2 kg) volunteered to participate. Prior to training, the subjects completed a 2-week accommodation period to become familiarized with the training protocol. Following the accommodation period, pre-testing was performed which included the SJ, CMJ, and AJ. All jump trials were performed on a hard surface and measured using a Vertec until there was no increase in jump height. The trial with the greatest jump height from each jump was used for analyses. Subjects then completed a 6-week plyometric training program on either a hard surface or soft surface. Following training, post-testing was performed identical to the pre-testing. A 2 (Surface: Hard and Soft) x 2 (Time: Pre-test and Post-test) repeated measures ANOVA was used to examine the mean differences in jump height values for the SJ, CMJ, and AJ. RESULTS: The results of the present study indicated that there were no significant 2-way interactions (SJ: p = .708, ηp2 = .02; CMJ: p = .483, ηp2 = .06; AJ: p = .330, ηp2 = .12) or main effects for Surface (SJ: p = .457, ηp2 = .07; CMJ: p = .477,ηp2 = .07; AJ: p = .373,  ηp2= .10), but there were significant main effects for Time (SJ: p < .001, ηp2 = .85; CMJ: p < .001, ηp2 = .85; AJ: p = .001, ηp2 = .74). For the SJ, CMJ, and AJ, the post-test values (SJ = 55.02 ± 8.77 cm; CMJ = 59.12 ± 9.41 cm; AJ = 62.05 ± 10.49 cm) were greater than the pre-test values (SJ = 50.59 ± 8.09 cm; CMJ = 56.03 ± 9.17 cm; AJ = 58.45 ± 9.75 cm). CONCLUSIONS: For the SJ, CMJ, and AJ, the current findings indicated that there were similar increases in jump height regardless of surface area. These findings suggested that there is a minimum intensity threshold, determined by the training surface area, necessary to induce training adaptations. Thus, professionals can tailor plyometric training programs to target either fast or slow stretch-shortening cycles by modifying the intensity via changes in surface area. PRACTICAL APPLICATIONS: Practitioners designing plyometric training programs to increase lower body vertical power may perform the training sessions on a soft surface or a hard surface and see similar improvements in vertical jump performance.

Acknowledgements: None