Supervisors info:
Αναστασιάδης Μ., Καθηγητής, ΤΕΦΑΑ, ΕΚΠΑ
Μπουντόλος Κ.,Καθηγητής, ΤΕΦΑΑ, ΕΚΠΑ
Μπάγιος Ι., Επίκουρος Καθηγητής, ΤΕΦΑΑ, ΕΚΠΑ
Summary:
One aspect that affects the direction, velocity and distance of the soccer ball is the placement of the supporting foot. The purpose of this study was to examine Ground Reaction Forces (GRF)on the supporting foot in the full instep kick, inside instep kick and outside instep kick, in two different approach angles (………) in correlation to the ball velocity (BV).
The subjects volunteering for this study were nine professional soccer players from the National Division. The subjects performed on specifically constructed floor three maximal effort instep soccer kicks on each condition (six conditions: three kicking types multiplied by two approach angles) to a 9,15 meters away goal (penalty). GRF were measured with a Kistler mobile forceplate (model 9286AA), while a specifically constructed digital electronic device (Bayios, 1998) was used to measure BV. Data of GRF were analyzed with Kistler’s BioWare software system. Regressions, one-way Anova (with six conditions) and post-hoc comparisons (Tukey, HSD), were included in the statistical analysis.
Ball Velocity. No significant differences were found for BV among the six conditions. Furthermore, during straight approach angle performance, the BV was significantly correlated to the second maximal vertical force (Fz2).
Time Variables: No significant differences were found for time variables among the six conditions.
Force Variables. Significant differences were found among the six conditions for the second maximal vertical force, minimum -between two maximal- vertical force, maximal medio-lateral force and maximal anterior-posterior force.
GRF generated on the supporting foot during instep kick can vary, according to the approach angle and the kicking type. On contrary, BV is not changed, while it is not affected by the most GRF time and force variables. A further search of the relation between the ball velocity and the second maximal vertical force is suggested.
