The discriminating factors of winning and losing in elite wheelchair tennis

Abstract

Technology is being used more and more to aid elite athletes in improving their performance. Recently there have been promising developments in the research using IMUs regarding wheelchair rugby and basketball. Applying this same measurement setup to wheelchair tennis could give better insight in the wheelchair mobility of wheelchair tennis athletes. This knowledge could aid the athletes in causing less sport related injuries, altering the focus of their training or even training entirely new aspects of the sport. This is why this research will be answering the research question: “What is/are the most influential factor(s) regarding the mobility of wheelchair tennis athletes to discriminate between the winning and losing player?”. We define the wheelchair mobility performance as all the measurable parameters related to the movements of the athlete. These mainly consist of the velocities and accelerations reached by the athletes. The measurements resulted in three different ways to output variables. Match statistics, these include information about the distance travelled, turns made and points played during the match. This was chosen to give general insight into the match. The wheelchair mobility performance (WMP), shows information about the velocities and accelerations during the match. This was chosen to compare the velocities and accelerations of athletes, they are plotted against the average value of the entire database of all measurements, this will be a standardized baseline to compare the results to. Lastly the speed zone plots, the plots give an indication of how long the athlete has been driving within a certain velocity range. To give better insight in the dynamic of the match all outputs also includes the constraints of winning/losing and serving/receiving. It is therefore possible to compare the differences between won and lost points and served and received points. There was also experimented with the possibility of making a plot that shows the location of the athlete on the field as a heatmap. However, because the IMUs only record accelerations the cumulative error to distance had to be manually adjusted for, therefore this was only done for one match as a pilot case. The match statistics, WMP plots and speed zone plots showed no significant differences between winning and losing points. Therefore, this study found that the mobility performance has no deciding effect on the outcome of a tennis match. The technique used to hit the ball and place it on the right spot in the field will probably be the determining factor here. This said, the mobility does however have to be above a certain threshold for the player to compete at a certain level of play, so neglecting it completely is not recommended, however the focus should be on the technique that involves hitting the ball. The heatmap case shows that the winning player plays more aggressive, but whether he is playing aggressive because he is winning or winning because he is playing aggressive cannot be concluded by this research.