تأثير التعب على الدقة و بعض المتغيرات الكينماتيكية لتسديدة ركلة الجزاء لدى لاعبي أندية الدرجة الأولى لكرة القدم في شمال فلسطين

الملخص EN

The aim of this study was to identify the effect of fatigue on accuracy and some kinematic variables of penalty kick in football, as well as, to identify the most study variables are affected by fatigue.

In order, to achieve the goals of this study, the Quasi- experimental approach has been applied on (9) male football players.

In addition, the sample was selected in a deliberate manner.

Where each player kick (10) balls from the penalty point: (5) before starting the fatigue protocol and (5) balls after applying the protocol, so that the total number of attempts (90) shot.

Additionally, the researchers used tow camera to filmed the players while kick balls.

One placed vertically at the lateral level, the other placed vertically behind the player and on the front.

Furthermore, a total of (74) successful attempts were analyzed by using Kinovea kinetic analysis program.

The study examined the following variables: distance, time and speed of approach, the speed of the foot of the leg kick, the speed of the ball at the release moment, the Angular speed of the knee joint at the moment of kicking, the release angle of the ball, the angle of the knee of the leg at the touch moment of the ball, the angle of the trunk at the kick ball moment, maximum horizontal displacement of the foot of the kick leg, accuracy kick.

The results of the study showed statistically significant differences in the values of kinematic variables before and after the application of the fatigue protocol and for the benefit of post measurement.

There are also statistically significant differences in the level of accuracy of kicking and in favor of post measurement.

Furthermore, the results of the study showed that the accuracy of the kick variable was the most variable affected by fatigue by (29.3) % percentage.

The researchers recommend the need to kick penalties after the completion of the training unit and after the exercises that are characterized by high intensity