A kinematical study of Read and Commit block in Volleyball Introduction Two tactic systems are used for blocking in volleyball: the Read Block System (RBS) or the Commit-Option Block System (CBS). In the RBS, the blocker starts close to the net looking to the opponent’s setter, ready to react to different types of set. In the CBS, the blockers has to follow the approach of the specific opposite hitter without worrying about the set. In both cases the key point for the effectiveness of the block is the lateral movement before the jump. Two types of footwork techniques are normally used: the Cross-over (CO) and the Slide Step (SS) 1,2. Previous studies jumping vertically showed significant differences between systems3. It’s the same after a lateral movement? Methods Subjects: 4 males elite level players were acquired by means of stereo-photogrammetry (6 cameras, 100 Hz frequency 16 markers). Simulating the RBS, players had to carry out block exercises as answer to a stimulus: an operator on the other side of the net moved a 2 markers stick up, right or left in order to simulate the possible sets in zone 2, 3 or 4. The player was prompt to react, reading the coach miming of the opponent set in all the three possible directions (left, right, or up) and then moved or jumped consequently. In the CBS, the player decided by himself when start. Three trials for each type of block were acquired. The best trials were identified from the maximum jump height reached. The following variables were selected: temporal phases of steps, elevation, knee flexion angles (at the countermovement). The non-parametric Wilcoxon test was performed to compare the two type of blocking techniques (α=0.05). Results No significant differences were found between the two tactic systems. Discussion/Conclusion Footwork techniques can be trained at the same time in order to be applied in both tactics. Thus, the difference in blocking performance seems to depend mostly by the decision making process and in the control of arms and hands when contacting the ball. References 1. Cox R. H., Noble, L., & Johnson, R. E. (1982). RQES, 53 (2), pp. 101-107. 2. Buekers, M. J. (1991). RQES, 62 (2), 232-2 3. Lobietti R., Fantozzi S., Merni F. (2006) In: XXIV ISBS Congress Vol.1 pp. 151-154
Read and Commit block in Volleyball / Lobietti R.; Fantozzi S.; Stagni R.; Merni F.. - In: COACHING & SPORT SCIENCE JOURNAL. - ISSN 1590-7880. - STAMPA. - 3 (2):(2008), pp. 46-46. (Intervento presentato al convegno Verona-Ghirada Team Sport Conference tenutosi a Treviso nel 7-8 giugno 2009).
Read and Commit block in Volleyball
LOBIETTI, ROBERTO;FANTOZZI, SILVIA;STAGNI, RITA;MERNI, FRANCO
2008
Abstract
A kinematical study of Read and Commit block in Volleyball Introduction Two tactic systems are used for blocking in volleyball: the Read Block System (RBS) or the Commit-Option Block System (CBS). In the RBS, the blocker starts close to the net looking to the opponent’s setter, ready to react to different types of set. In the CBS, the blockers has to follow the approach of the specific opposite hitter without worrying about the set. In both cases the key point for the effectiveness of the block is the lateral movement before the jump. Two types of footwork techniques are normally used: the Cross-over (CO) and the Slide Step (SS) 1,2. Previous studies jumping vertically showed significant differences between systems3. It’s the same after a lateral movement? Methods Subjects: 4 males elite level players were acquired by means of stereo-photogrammetry (6 cameras, 100 Hz frequency 16 markers). Simulating the RBS, players had to carry out block exercises as answer to a stimulus: an operator on the other side of the net moved a 2 markers stick up, right or left in order to simulate the possible sets in zone 2, 3 or 4. The player was prompt to react, reading the coach miming of the opponent set in all the three possible directions (left, right, or up) and then moved or jumped consequently. In the CBS, the player decided by himself when start. Three trials for each type of block were acquired. The best trials were identified from the maximum jump height reached. The following variables were selected: temporal phases of steps, elevation, knee flexion angles (at the countermovement). The non-parametric Wilcoxon test was performed to compare the two type of blocking techniques (α=0.05). Results No significant differences were found between the two tactic systems. Discussion/Conclusion Footwork techniques can be trained at the same time in order to be applied in both tactics. Thus, the difference in blocking performance seems to depend mostly by the decision making process and in the control of arms and hands when contacting the ball. References 1. Cox R. H., Noble, L., & Johnson, R. E. (1982). RQES, 53 (2), pp. 101-107. 2. Buekers, M. J. (1991). RQES, 62 (2), 232-2 3. Lobietti R., Fantozzi S., Merni F. (2006) In: XXIV ISBS Congress Vol.1 pp. 151-154I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
