Effects of volleyball plyometric intervention program on vertical jumping ability in male volleyball players

Effects of Combined Upper and Lower Limb Plyometric Training Interventions on Physical Fitness in Athletes: A Systematic Review with Meta-Analysis

Objective: We aimed to meta-analyze the effects of combined upper and lower limb plyometric training (ULLPT) on physical fitness attributes in athletes. Methods: A systematic literature search was conducted in Web of Science, SPORTDiscus, PubMed, and SCOPUS, for up to 13 August 2022. Controlled studies with baseline and follow-up measures were included if they examined the effects of ULLPT on at least one measure of physical fitness indices in athletes. A random effects meta-analysis was performed using the Comprehensive Meta-Analysis software. Results: Fifteen moderate-to-high-quality studies with 523 participants aged 12−22.4 years were included in the analyses. Small to large (ES = 0.42−1.66; p = 0.004 to <0.001) effects were noted for upper and lower body muscle power, linear sprint speed, upper and lower body muscle strength, agility, and flexibility, while no significant effects on static and dynamic balance were noted (ES = 0.44−0.10; all p > 0.05). Athletes’ sex, age, and training program variables had no modulator role on the effects of ULLPT in available data sets. Conclusions: ULLPT induces distinct neuro-muscular adaptations in the upper and lower body musculature and is an efficient method for enhancing athletes’ physical fitness.

Bilateral counter movement jump, squat, and drop jump performances in deaf and normal-hearing volleyball players: a comparative study

Since deaf athletes do not have any physical deficiencies, it is known that they can easily participate in sports competitions if their communication problems are resolved. This study aimed to compare the performances of olympic deaf and elite normal-hearing volleyball players in different jumping test protocols. A total of 26 male volleyball players participated in the study, comprised of 12 olympic level deaf and 14 elite level normal-hearing. Following anthropometric measurements, athletes performed bilateral counter movement, squat and drop jump tests on a force plate. Each test was performed 3 times with maximal effort separated by 45 seconds of passive recovery and the mean of the three trials was selected for analysis. Independent Samples t-test was used to compare the differences in mean values of jumping test parameters between the groups. Normal-hearing athletes are observed to have significantly better scores than deaf athletes in all test protocols. Considering that the number of studies on athletic performance in deaf athletes is limited, it can be said that our study will contribute to researchers and coaches in respect of detecting a key ability in volleyball, such as jumping, in different jump protocols.

Relationships of the 5-Jump Test (5JT) Performance of Youth Players With Volleyball Specific' Laboratory Tests for Explosive Power

Volleyball involves movements with and/or without horizontal approaches (i.e., spike jumps, jump setting, blocking). The 5-jump test (5JT) was suggested to assess lower limb explosive power of athletes competing in some disciplines (e.g., soccer, judo, running). It appears that no previous study has investigated the 5JT performance components in volleyball players. This study aimed to test the relationship between 5JT performance and two specific laboratory tests for explosive power (i.e., countermovement jump [CMJ] and squat jump [SJ]). Forty volleyball players (boys, mean age: 12.4 ± 0.8 years) were tested for 5JT, CMJ, and SJ tests. 5JT performance was expressed in absolute terms (m), and relative to leg length (5JT_LL) and body mass (5JT_BM). The SJ and CMJ tests were evaluated using the optojump photoelectric cells and the following data were collected: peak power (Pp) of jump (W, W.kg^-0.67), peak jumping force (F_peak, N), peak jumping velocity (V_peak, m/s), peak heights of CMJ and SJ (CMJ_H and SJ_H, respectively, cm). Only significant (p < .05) Pearson product-moment correlations (r) > 0.30 were considered. 5JT performance was significantly correlated with SJ, V_peak (r = 0.90), SJ_H (r = 0.88), Pp [W.kg^-0.67 (r = 0.86), W (r = 0.72)], F_peak (r = 0.45); and CMJ, V_peak (r = 0.82), CMJ_H (r = 0.80), Pp [W.kg^-0.67 (r = 0.89), W (r = 0.85)], F_peak (r = 0.73). 5JT_LL values were significantly related to SJ, Pp [W (r = 0.81), W.kg^-0.67 (r = 0.74)], V_peak (r = 0.82); and CMJ, Pp [W (r = 0.73), W.kg^-0.67 (r = 0.84)], V_peak (r = 0.75), F_peak (r = 0.67)]. 5JT_BM values were significantly related to SJ, Pp (W, r = −0.43). To conclude, in youth volleyball players, the 5JT may be viewed as an explosive strength diagnostic instrument under field circumstances.