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Jumping performance and take-off efficiency in two different age categories of female volleyball players

Jandova Sona, Janura Miroslav

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 2

55--61

EN

Vertical jump height is recognised as a determinant factor in elite volleyball performance. In previous studies there are different opinions on whether vertical jump height performance improves during maturation or not. The aim of this study was to assess the differences in jumping abilities in two different age groups of female volleyball players and to determine the take-off efficiency during repeated jumps. Methods: Seventeen female volleyball players from two different age categories – adults and under 16 years – participated in this study. Quattro Jump 9290BA force platform (Kistler, Winterthur, Switzerland) was used to assess the jumping performance during squat jumps, counter movement jumps, and 45-second continuous jumps. Results: Jumping performance did not differ significantly between the two groups. The main efficiency of the conversion of mechanical work into mechanical energy was only 24% and it decreased during the test. Conclusions: The influence of age on the jumping performance in a group of female volleyball players was not confirmed. Take-off efficiency was in both groups quite low and it did not improve during the test.

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Somatotype variables related to strength and power output in male basketball players

Buśko K., Pastuszak A., Lipińska M., Gryko K.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 2

161--167

EN

The purpose of this study was to investigate the relationship between somatotype, muscular strength, power output measured in maximal cycle ergometer exercise bouts, and maximal power output and height of rise of the body mass centre (jump height) measured in akimbo counter movement jump (ACMJ), counter movement jump (CMJ) and spike jump (SPJ), in male basketball players. Methods: Thirteen male basketball players (second division, age 19.4±0.8 years, body height 192.9±5.6 cm, body mass 88.8±8.6 kg, training experience 9.3±0.8 years) participated in the study. Somatotype was determined using the Heath-Carter method. Maximal joint torques were measured under static conditions. Power output was measured in 2 maximal cycle ergometer exercise bouts, 10 s each, with increasing external loads equal to 7.5 and 10.0% of the body weight (BW). All jump trials (ACMJ, CMJ and SPJ) were performed on a force plate. Results: The mean somatotype of basketball players amounted to: 2.8-4.2-3.2. Sum of the joint torques for left and right lower extremities (0.613), trunk (0.631) and all six measured muscle groups (0.647) were significantly correlated (p<0.05) with mesomorphy and ectomorphy. Conclusion: It can be assumed that basketball players’ anthropometric characteristics can influence their level of performance but it is not a decisive factor.

3

Balance disorders caused by running and jumping occurring in young basketball players

Struzik A., Zawadzki J., Pietraszewski B.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 2

103--109

EN

Purpose: Body balance, as one of the coordination abilities,is a desirable variable for basketball players as regards the necessity of efficient responses in constantly changing situations on a basketball court. The aim of this study was to check whether physical activity in the form of running and jumping influences variables characterizing the process of keeping body balance of a basketball player in the standing position. Methods: The research was conducted on 11 young basketball players. The measurements were taken with a Kistler force plate. Apart from commonly registered COP displacements, an additional variable describing the process of keeping body balance by a basketball player was ankle joint stiffness on the basis of which an “Index of Balance–Stiffness” (IB-S) was created. Results: Statistically significant differences were obtained for the maximum COP displacements and ankle joint stiffness between measurements of balance in the standing position before and after the employed movement tasks whereas there were no statistically significant differences for the aforementioned variables describing the process of keeping balance between measurements after running and after jumping. Conclusions: The research results indicate that the employed movement activities brought about significant changes in the process of keeping balance of basketball player in the standing position which, after the run performed, remain on a similar level to the series of jumps being performed. The authors attempted to establish an index based on the stiffness which yields a possibility to perceive each basketball player as an individual person in the process of keeping balance.

4

Evaluation of selected biomechanical parameters in female team sports players

Pietraszewski B., Struzik A.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 4

103--108

EN

The aim of this research was to evaluate the biomechanical parameters of lower limbs and their influence on height of vertical jump. The research was conducted on a group of females practicing basketball and volleyball. The following equipment was used during the experiment: a force plate by Kistler, a Biometrics electrogoniometer and a specially designed chair to measure static torque by OPIW Opole. The results indicated that the jumping abilities of the examined athletes were poor. No statistically significant correlations were observed between knee static torque and heights of vertical jumps: CMJ and DJ. The authors suggest modification of the McClymont index (RSI) to evaluate the selection of platform height during plyometric training. Such modification would enable better choice of loads and better training control of the subject.