Kinematic and Electromyographic Analysis of Infront Curve Soccer Kick
Hiroki Ozaki and Kazuo Aoki
[Received September 25, 2007 ; Accepted December 4, 2007]
Two types of curve kicks are seen in football (soccer). One is a kick in which the player attempts to rub the ball with the toe trying to keep in contact with the ball as long as possible (hereafter called the Usual Curve Kick). This is frequently described in common tutorial manuals. The second is a kick in which the ball is spun by the angle of attack which is made by the swing direction of the kicking foot and the direction of the impact surface (hereafter called the Angle Curve Kick). No studies have examined the difference between these two types of kicking. The purpose of this study was to clarify these two types of curve kicks using kinematic and electromyographic analysis. Kick movements confined to the vicinity of impact were examined. The subjects were six male college football players. In order to observe the kicks from below, a platform with two plates of hardened glass on top was fabricated. Kicking movements were shot with a high speed camera (250 Hz). The subjects tried to kick a ball at their full strength five times for each type of kick, namely the Usual Curve Kick, the Angle Curve Kick and the Inside Kick which was included for the sake of comparison. The direction of the kicking foot, the swing direction, the initial ball velocity and the number of ball rotations were obtained using the images. Results indicate that there was no great difference in performance between the Usual Curve Kick and the Angle Curve Kick, though muscle discharge of the adductor muscle group showed greater values in the Usual Curve Kick. The impact point of the kick was nearest to the toe in the Usual Curve Kick. In the Usual Curve Kick, the direction of the kicking foot changed toward the right at the target suggesting that the hip joint could externally rotate. These findings led to the conclusion that in a comparison between the Usual Curve Kick and the Angle Curve Kick, the Angle Curve Kick was considered to impose less strain on the adductor muscle group in the case of similar performance level.
Keywords: Curve Kick, Angle of attack, EMG, impact
[Football Science Vol.5, 26-36, 2008]