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The primary objective of this study was to design a digging agility system that was used to analyze the effectiveness of 6 weeks of plyometric training on volleyball players. A total of 24 highly trained college male volleyball players were recruited for this study. The players were equally divided into a plyometric training group and a control group. The agility T-test, peak power output test, 10-meter sprint, and digging agility test were used to examine the effects of plyometric training on the digging agility of volleyball players. One-way analysis of covariance was conducted to examine the differences in the variables between groups. The results reveal that after 6 weeks of plyometric training, the plyometric training group had significant improvements on the agility T-test, digging agility test, and peak power output tests, with statistical power values all greater than 90%. The plyometric training group significantly improved by 2.68% on the agility T-test, 2.35% on the digging agility test, and 7.32% on the peak power output test. The results indicated that appropriate plyometric training can enhance the agility of lateral movements and peak output of vertical jumps, as well as enable players to rapidly complete movements during a moving defense.

Whole body vibration (WBV) has been suggested to improve athletes’ neuromuscular strength and power. This study investigated the effect of single WBV stimulation on volleyball-specific performance. The participants were 20 elite male volleyball players who performed a 1-min warm-up exercise on a vibration platform at a frequency of 30 Hz and peak-to-peak displacement of 2 mm. After the warm-up exercise, the participants performed a blocking agility test (BAT), 10-m sprinting test, agility T-test, and counter movement jump test. We compared the participants’ performance at four time points (Pretest, Post 0, Post 1, and Post 2). The results revealed that the participants’ BAT performance and maximum rate of force development improved significantly 1 min after the vibration stimulation (p

The agility T-test and countermovement jump test have long been used to examine the agility of athletes. However, for some sports, newer systems of evaluation are being designed for specific movements. The goal of this study was to design a blocking agility system and apply it to analyzing the efficiency of 6 weeks of plyometric training on volleyball players. A total of 26 male volleyball players in Taiwan participated in the study. The participants were divided into a plyometric training group and a control group. The agility T -test, countermovement jump test, and blocking agility test were used to examine the influence of plyometric training on the blocking agility of volleyball players. A single-factor analysis of covariance was applied to obtain the variables for the two groups. There was no significant difference between the groups on the agility T -test. On the countermovement jump test and blocking agility test, the plyometric training group performed significantly better than the control group. Also, the power values of blocking agility were higher than 90%, which demonstrated very good validity. The results of this study indicate that appropriate plyometric training can increase the rate of force development for vertical jumps and significantly enhance the combined agility of volleyball players in terms of lateral-movement speed and quickness, which enable players to rapidly perform blocking actions.

In volleyball matches, there are three minute intervals between sets. Therefore, the improvement of the muscle output ratio is one of the most import foundational physical elements for the players. The purpose of this study was to investigate the effects of plyometric training on the changes in electrical signals in the lower limb muscles of male college volleyball players during continuous blocking and to examine the benefits of plyometric training on blocking agility and maximum vertical jump height. In this study, twenty elite male college volleyball players were recruited and divided into a plyometric training group (PTG) and a control group (CG). The wireless electromyography was used for data acquisition, and the electrodes were applied to the left and right rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius. The median frequency was used as the measurement of the electromyographic signals during the jumping blocks. This study used covariate analysis methods, with previously measured results used as covariates to perform a two-way analysis of covariance for the independent samples. Based on the results of this study, after 6 weeks of training, the median frequency of the rectus femoris (2.13% to 4.75% improved) and that of the tibialis anterior muscles (4.14% to 7.71% improved) were significantly lower in the PTG than in the CG. Additionally, the blocking agility increased by 6.26% and the maximum vertical jump height increased by 3.33% in the PTG compared to the CG. The findings provide important insights on the neuromuscular status for volleyball players during continuous blocking jumps. Six weeks of appropriate plyometric training can facilitate the performance of volleyball players.

The objectives of this study were to assess volleyball speed and impact force and to analyse the differences between these properties. Three types of volleyballs were used in this study: MVA200, weighing 270 ± 10 g; Prototype Ball A (Type A), weighing 270 ± 10 g; and Prototype Ball B (Type B), weighing 340 ± 10 g. Vertically downward 3-m impact tests were conducted using a serving machine, force plate, and radar speed gun. Contact time, ball speed, mean force, peak force, total impulse, initial momentum, incident impulse, and lost momentum were calculated. Intraclass correlation coefficients were calculated to evaluate the reliability of the data, and one-way analysis of covariance and Scheffe’s post hoc analysis were used to analyse the variables of the three ball types. The paired samples t-test was used to compare the difference between initial momentum and incident impulse. The results indicated that the intraclass correlation coefficients of the three ball types were 0.998 (MVA200), 0.997 (Type A), and 0.999 (Type B). Type B considerably surpassed Type A and MVA200 in mechanical factors, and Type A was significantly superior to MVA200 in incident impulse and lost momentum. The results indicated that different volleyballs of the same size, weight, and internal air pressure have dissimilar mechanical features and implied that slight adjustment to ball structure can cause substantial changes in the specific characteristics. In addition, the mass increased the lost momentum, which might cause the ball to bounce unpredictably.