Tine Sattler1, Damir Sekulic2, Michael R Esco3, Ifet Mahmutovic4, Vedran Hadzic1. 1. University of Ljubljana, Faculty of Sport, Slovenia. 2. University of Split, Faculty of Kinesiology, Croatia; University of Split, University Department of Health Care Studies, Croatia. Electronic address: dado@pmfst.hr. 3. University of Alabama, Department of Kinesiology, USA. 4. University of Sarajevo, Faculty of Physical Education and Sport, Bosnia and Herzegovina.
Abstract
OBJECTIVES: Isokinetic-knee-strength was hypothesized to be an important factor related to jumping performance. However, studies examining this relation among elite female athletes and sport-specific jumps are lacking. This investigation determined the influence of isokinetic-knee flexor/extensor strength measures on spike-jump (offensive) and block-jump (defensive) performance among high-level female volleyball players. DESIGN: Cross-sectional laboratory study. METHODS: Eighty-two female volleyball athletes (age = 21.3 ± 3.8 years, height = 175.4 ± 6.76 cm, and weight = 68.29 ± 8.53 kg) volunteered to participate in this study. The studied variables included spike-jump and block-jump performance and a set of isokinetic tests to evaluate the eccentric and concentric strength capacities of the knee extensors (quadriceps - Q), and flexors (hamstring - H) for both legs. Both jumping tests showed high intra-session reliability (ICC of 0.87 and 0.95 for spike-jump and block-jump, respectively). The athletes were clustered into three achievement-groups based on their spike-jump and block-jump performances. RESULTS: For the block-jump, ANOVA identified significant differences between achievement-groups for all isokinetic variables except the Right-Q-Eccentric-Strength. When observed for spike-jump, achievement-groups differed significantly in all tests but Right-H-Concentric-Strength. Discriminant canonical analysis showed that the isokinetic-strength variables were more associated with block-jump then spike-jump-performance. The eccentric isokinetic measures were relatively less important determinants of block-jump than for the spike-jump performance. CONCLUSIONS: Data support the hypothesis of the importance of isokinetic strength measures for the expression of rapid muscular performance in volleyball. The results point to the necessity of the differential approach in sport training for defensive and offensive duties.
OBJECTIVES: Isokinetic-knee-strength was hypothesized to be an important factor related to jumping performance. However, studies examining this relation among elite female athletes and sport-specific jumps are lacking. This investigation determined the influence of isokinetic-knee flexor/extensor strength measures on spike-jump (offensive) and block-jump (defensive) performance among high-level female volleyball players. DESIGN: Cross-sectional laboratory study. METHODS: Eighty-two female volleyball athletes (age = 21.3 ± 3.8 years, height = 175.4 ± 6.76 cm, and weight = 68.29 ± 8.53 kg) volunteered to participate in this study. The studied variables included spike-jump and block-jump performance and a set of isokinetic tests to evaluate the eccentric and concentric strength capacities of the knee extensors (quadriceps - Q), and flexors (hamstring - H) for both legs. Both jumping tests showed high intra-session reliability (ICC of 0.87 and 0.95 for spike-jump and block-jump, respectively). The athletes were clustered into three achievement-groups based on their spike-jump and block-jump performances. RESULTS: For the block-jump, ANOVA identified significant differences between achievement-groups for all isokinetic variables except the Right-Q-Eccentric-Strength. When observed for spike-jump, achievement-groups differed significantly in all tests but Right-H-Concentric-Strength. Discriminant canonical analysis showed that the isokinetic-strength variables were more associated with block-jump then spike-jump-performance. The eccentric isokinetic measures were relatively less important determinants of block-jump than for the spike-jump performance. CONCLUSIONS: Data support the hypothesis of the importance of isokinetic strength measures for the expression of rapid muscular performance in volleyball. The results point to the necessity of the differential approach in sport training for defensive and offensive duties.
Authors: Victor Coswig; Anselmo De Athayde Costa E Silva; Matheus Barbalho; Fernando Rosch De Faria; Claudio D Nogueira; Mariane Borges; Jéssica R Buratti; Ivaldo B Vieira; Francisco Javier López Román; José I Gorla Journal: JMIR Mhealth Uhealth Date: 2019-01-30 Impact factor: 4.773
Authors: Alexandre R M Pelegrinelli; Laís F Dela Bela; Mariana F Silva; Lucas C R Rodrigues; João P Batista; Leandro C Guenka; Josilainne M Dias; Lee E Brown; Rodrigo L Carregaro; Felipe A Moura; Jefferson R Cardoso Journal: S Afr J Physiother Date: 2019-06-11