PURPOSE: 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.

Palacký University Faculty of Phsical Culture Olomouc Czech Republic

Technical University of Liberec Faculty of Mechanical Engineering Lieberec Czech Republic Palacký University Faculty of Phsical Culture Olomouc Czech Republic