Behrouz Abdoli, Alireza Farsi and Shaghayegh Modaberi
this research aimed to study the effect of visual Information and contextual interference on learning of underhand Volleyball serve and Exploring Specificity of Practice Hypothesis. Participants in this study were 80 healthy right handed female students that randomly divided into eight groups. The subjects practiced for five days, 30 attempt every day in random, serial, constant and specific in both vision and no vision conditions and finally participated in the transfer test. Results showed the performance dominant in visual condition. Results also showed that specific practice (According to specificity of practice hypothesis, People tends to practice in the conditions that the receiving sensory information and contextual characteristics are similar to the testing conditions) and random practice (motor programs recruitment in the new conditions) groups has better performance than other practice groups. Overall, results of current study revealed that despite the constant practice group has better performance compared to other groups in the acquisition phase, but random and specific practice groups was better that serialand constant groups in the transfer phase. Therefore the results of this study supported the theory of contextual interference and specificity of practice hypothesis.
