Affiliations: [a] Department of Physical Education and Sport Sciences of
Trikala, University of Thessaly, Greece | [b] Department of Physical Education and Sport Sciences of
Serres, Aristotle University of Thessaloniki, Greece | [c] Department of Physical Education and Sport Sciences of
Thessaloniki, Aristotle University of Thessaloniki, Greece
Abstract: The purpose of this study was to examine the relationship between
vertical jumping performance and isokinetic moment of force of knee extensors,
hip extensors and ankle plantar flexors in adult males. Twenty-nine males
performed squat and counter movement jumps on an Egrojump device. The peak
jumping height and the total work (height × body mass) were used as
indicators of vertical jump performance. The subjects also performed three
submaximal and three maximal isokinetic efforts of the hip extensors, knee
extensors and ankle plantarflexors at angular velocities of 60, 120 and 180
°·s^{-1} on Cybex Norm Dynamometer. Pearson's
product correlation tests indicated that there was a significant (p<0.05)
positive relationship between vertical jumping height and total work with hip
and knee extension moments, whereas low correlation coefficients between
isokinetic moment of the ankle plantarflexors and jumping performance were
found p<0.05). Multiple regression analysis indicated that linear
combinations of isokinetic torques accounted for 38% countermovement and squat
jumping height variance, respectively. In contrast, regression models using
isokinetic torques could predict jumping work accounting for 75% (squat jump)
of the variance. The above results indicate that there is a moderate to high
relationship between isokinetic knee and hip extension torques and vertical
jump performance parameters, especially when jumping height is multiplied by
subject's body weight. Furthermore, it appears that when using a linear
combination of isokinetic torques from hip and knee joint muscle groups the
multiple relationship between isokinetic tests and jumping performance is
higher.
