A three-dimensional study of the maximum linear velocity results for parts and center of gravity of body and the racket and the ball when performing the backhand (straight - diagonal) in tennis

Abstract

The backstroke in tennis is characterized by its difficulty and because of its less use. It is a defensive and offensive skill alike. It is performed in two types (straight and diagonal). This skill lacks a lot of information and studies are almost devoid of it, and the information we receive in the direction of biomechanics is very little. Knowing the behavior of the kinematic variables from the three directions is very important, as the availability of this new information will lead to the new horizons about this skill.

The lack of three-dimensional analytical studies with modern and more accurate programs to include all the variables of this strike led us to carry out a study using the three-dimensional analysis in the international (APAS) program, because the analysis in this program is close to the truth, and the movement is studied in its real space, which helps the trainers In rationing their work, this is because the three dimensions determine all the paths of the parts of the body or the ball in space in terms of approach, height, and distance, and give the variables their value more accurately. And the comparison between the two types, and the sample included two players from Al-Kufa Club in Al-Najaf Governorate, and they represent the Iraqi national team. It is noted that the left foot is the late foot, and it is noted that the speed it exerted in the diagonal type was greater, because the player directs the ball in a way that contradicts its true direction, which requires more pushing with this foot. Likewise, the right hip is the hip on which the body will rotate in the diagonal type because the right foot It is the pivot foot, and the instantaneous velocity was greater in the diagonal backhand kick in order to deliver the ball to an area farther than the straight backhand kick accuracy area.