Effect of string vibration damper of tennis racket on myoelectric activity of wrist extensors

The purpose of this study was to investigate the effect of String Vibration Damper on the myoelectric activity of the wrist extensors during the impact phase of backhand stroke technique.15 elite and 15 novice tennis players with an age ranging from18-25 years volunteered to participate in this study. Only one racket was used and was impacted by a pressurized ball. That was subjected to a constant velocity. The ball impacts were directed the racket throat area with and without using the String Vibration Damper. The participants were not allowed to see the ball impacts, as stand was placed between the participant and the racket. The experiment was repeated three times at the same day with rest periods in-between. The wrist extensors EMG data were collected with and without using the String Vibration Damper. Results revealed that there was no significant effect of using String Vibration Damper on the mean values of maximum EMG activity of the examined muscles (P>0.05). But, the decrease in the myoelectric activity of tennis beginners is significant, indicated that it may be preferable to use the string vibration damper with tennis beginners to protect them against the occurrence of lateral elbow pain. In conclusion, the results of the study do not support the concept of using the String Vibration Damper to reduce the myoelectric activity of the wrist extensor during tennis playing.