Effect of the Physical Effort Levels on the Angular Impact Kinematics When Performing Kicking Accuracy with Instep in the Soccer Junior

El-Sayed Abo Abda, Hassan; Ibrahim El-Agamy, Omaima; Al-Mangor, Abdulkareem

doi:10.21608/jass.2013.84844

Effect of the Physical Effort Levels on the Angular Impact Kinematics When Performing Kicking Accuracy with Instep in the Soccer Junior

Document Type : Original Article

Authors

Faculty of Physical Education for Boys, Alexandria University, Alexandria, Egypt

10.21608/jass.2013.84844

Abstract

Kicking in soccer with accuracy is influenced with a group of factors. It is noted the paucity of the scientific studies which addressed other variables related to the effect of the physical effort levels on the kicking performance. Most of the treatments have done on kicking from stationary situations without paying attention to study kicking performance skill in the moving play situations a simulation to what occurring during the actual practice(the game). Therefore the purpose of this study was to know the effect of the different physical effort levels on the change in the angular kinematics impact when performing kick accuracy of a moving ball with front instep of the foot in soccer players.(N=10) junior soccer players (varsity players) age: 16.8 ±0.55 years, height 173.4 ±7.41 cm., weight 66.7 ±8.65 kg. have completed five levels of physical effort according to Hoff Test(10 min. for each level). In this test the levels were determined based on: running distance(m.), lactic acid concentration in blood (mmol ⁄L), heart rate during the test and on kicking performance(b ⁄min.) and perceiving exertion scale(deg.). The best trial(the most accurate) from four front instep kick trials of a complex skill ending with shooting were analysed by using Motion Track program 3.D. and by using 3 camera(25 HZ). The first camera to the side of the player, the second to the side of the goal, the third behind the player and in front of the goal. The first and third cameras were used to analyze the angular kinematic variables of the impact phase(impact between foot and ball). Second and third cameras to define accuracy level. The results revealed that there were statistical significant differences (P<0.05) between the different physical effort levels in the kinematic variables related to the angular distance variables: angle of knee and hip joints of both kicking and supporting legs and ball release angle and angle of the knee extension and hip flexion of the kicking leg, also to know the kinematic variables relevant to the angular velocity of the variable of: angular velocity of foot and shank of both kicking and supporting legs and ball velocity. It was found a great effect size of these variables in favor of the low and moderate physical effort levels comparing to the high sub-maximum and maximum levels. The present results suggested that Hoff Test protocol which simulate the actual practice(the game)lead to an impairment of kicking performance in soccer because there were functional and physiological changes which in turn changed kicking performance mechanics in soccer.

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