Informace o publikaci
EVALUATION OF SPORT TECHNIQUE IN TENNIS BASED ON 3D KINEMATIC ANALYSIS
| Autoři | |
|---|---|
| Rok publikování | 2016 |
| Druh | Článek ve sborníku |
| Konference | 10th INTERNATIONAL CONFERENCE ON KINANTHROPOLOGY "Sport and Quality of Life" |
| Fakulta / Pracoviště MU | |
| Citace | |
| Obor | Sport a aktivity volného času |
| Klíčová slova | sport technique; tennis; 3D kinematic analysis |
| Popis | ABSTRACT Sport technique in tennis represents one of the most important factors of sport performance. This study deals with 3D kinematic analysis of tennis shots and with an evaluation of sport technique. The aim of this research was to use 3D kinematic analysis and obtain precise kinematic characteristics in chosen phases of tennis shots which are required for an evaluation of tennis technique. A male tennis player has been tested for the purposes of this case study in thirty attempts in standard conditions. Three most interesting forehand shots have been analysed in detail. The same ball velocity and the same place were generated by the tennis machine. The tested person A.P. was 15 years of age. We focused on key time moments in the performance of motion during repeated forehand strokes. The first moment was when the time of maximal acceleration of upper tennis racket occurred, the second moment was the time when maximal speed of upper tennis racket was recorded, the third moment occurred at the time of contact between the tennis racket and the ball, and finally the highest and lowest values of kinematic parameters of all segments of dominant upper extremity (right) were taken into the consideration. The following kinematic parameters have been chosen: velocity, acceleration of dominant upper extremity, centre of gravity and upper racket, height, lateral and forward-backward distance of centre of gravity, angles in both knees, elbows and body bending. The highest values of acceleration of upper racket during stroke are achieved when the whole kinematic chain of body segments are finished. The best attempt was represented by the highest values of velocity and acceleration of upper racket. The achieved values are: 19.744 m/s and 206.520 m/s2. The contact between the racket and the ball should happen a moment later. We believe that the most important segment of tennis player system is the upper racket location which is responsible for the quality of tennis shot. Many velocity, acceleration and angle parameters have been measured, but for the evaluation of tennis technique have been chosen only those which achieved required values and forehand shot was successful. However, the positive results of some of the shots parameters were achieved due to decelerations of some other segments of dominant upper extremity just before the contact with the ball. The moment of maximal velocity of upper racket occurred nearly at the same time as the contact of the racket with the ball. Acceleration of upper racket at this moment was lower than maximal acceleration recorded little bit sooner. Movement of the centre of gravity must be smooth enough and in a sufficient range. This study also brings specific values for classification of forehand shots and it confirms that optimal kinematic chain determines the quality of tennis techniques. These objective results can be helpful for tennis coaches and support their subjective expert evaluation. |