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The purpose of this study was to investigate the possible arm swing effect on the biomechanical parameters of vertical counter movement jump due to differences of the compliance of the take-off surface. Fifteen elite male beach-volleyball players (26.2 ± 5.9 years; 1.87 ± 0.05 m; 83.4 ± 6.0 kg; mean ± standard deviation, respectively) performed counter movement jumps on sand and on a rigid surface with and without an arm swing. Results showed significant (p < .05) surface effects on the jump height, the ankle joint angle at the lowest height of the body center of mass and the ankle angular velocity. Also, significant arm swing effects were found on jump height, maximum power output, temporal parameters, range of motion and angular velocity of the hip. These findings could be attributed to the instability of the sand, which resulted in reduced peak power output due to the differences of body configuration at the lowest body position and lower limb joints' range of motion. The combined effect of the backward arm swing and the recoil of the sand that resulted in decreased resistance at ankle plantar flexion should be controlled at the preparation of selected jumping tasks in beach-volleyball.

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Giatsis, G., Lopez Martinez, A.B., & Gea García, G.M. (2015). The efficacy of the attack and block in game phases on male fivb and cev beach volleyball. A review. J. Hum. Sport Exerc., 10(2), pp.537-549. The aim of this study was to investigate the efficacy and differences of the attack, block, and reception in side out and counter-attack phases during beach volleyball games. A total of 80 games of FIVB World Tour and European Championships were analyzed. The technical skills analyzed were the type and efficacy of the attack, the type of block, and the efficacy of reception. The sample included 13.939 rallies, including attack (n=7.090), block (n=7.090), and serve reception (n=5.161). Descriptive statistics were applied in order to obtain frequencies and percentages. Inferential statistics were calculated (p<.05) through chi square tests. The results showed that the spikes were more frequent values than shots at both side out and counterattack phases. Attack errors and kills were the more frequent values in both phases. Perfect receptions showed a kill percentage similar to situations when the reception was limited. It was concluded that players should make fewer errors when spiking, and coaches should pay more attention to fake blocks during both side out and counter-attack phases.

The purpose of this investigation was to detect whether differences exist concerning the dynamic and kinematic parameters of vertical squat jump (SJ) on rigid (RS) and sand (SS) surface. Fifteen elite male beach volleyball players (age: 25.6 +/- 6.2 years; height: 188.0 +/- 3.5 cm; body mass: 83.2 +/- 6.0 kg; mean +/- SD, respectively) performed SJ. Force platform and kinematic analyses were used with paired sample T-tests to evaluate the differences. Vertical jump height was significantly smaller (p < .001) on SS than RS. Maximal force and maximal power were significantly higher on RS than SS (p < .05 and p < .01 respectively). Impulse time was larger in SS but with no significant difference (p = .286). Kinematic analysis revealed significant differences between the values of ankle joint during starting posture (p < .01) and of hip joint at the moment of take-off (p < .05). Ankle joint range of motion and angular velocity was larger in SS (p < .05). In conclusion, SJ height on SS was smaller than on RS because of the compliance and the instability of the sand. This resulted in a reduction in maximum force and take-off velocity. Furthermore, the compliance of SS made it hard for the ankle to push along the vertical axis of the movement of the body and as a result it slipped behind in an attempt to maximize propulsion. As a result, the body tries to balance and equalise this movement and move the hip to larger extension.