تأثیر کانون توجه در فعالیت عضلات شانه هنگام ضربه فورهند درایو تنیس روى میز

Objective: The aim of this study was to evaluate the impact of the external focus of attention on the rotator cuff muscle activity for the timely hit forehand drive by table tennis players.

Methods: Twelve professional table tennis players with mean age of 26.5 years voluntarily participated in this study. The electrical activities of the muscles of the shoulder girdle using M.A 300 machine and bipolar electrodes surface under two conditions .First with external focus of attention and then without such attention were recorded, first without any guidance blows forehand drive was carried out by subjects (without focus). Then such subject was asked to focus their attention on the area marked for the ball landing (external focus of attention).

     Muscle activities in both preparation and tapping phases were analyzed the three –dimensional (200 Hz, Vicon, with four camera series T) motion analysis system was used to obtain the data. Data was analyzed by running reported measures ANOVA at a significance level of p<05.

Results: In without external attention situation, muscle activity did not change significantly compared with the external focus of attention situation (p>0.05) but the different between the intensity of muscle activity was meaningful. This suggests that there is a mutual influence between the two attention factors and muscles (p=0.03), that is, orientation can have a significant effect on the severity of muscle contraction. Intensities of muscle contraction in the preparation and tapping were different (p<0.05).

Conclusion: On the forehand drive technique, the anterior deltoid muscle has the most activity. The type of focus and attention had a significant impact on the change of activity of muscles relative to each other, and the greatest impact is on the reduction of activity of the infraspinatus muscle. This type of focus delays fatigue and results in an increase in the efficiency of neuromuscular in the activities of skills.