According to Specificity of practice hypothesis, availability of visual information

specially during performing tasks witch vision has an important role in improving

the accuracy, causes further performance decrements in No-vision transfer test.

The purpose of the current study was to examine the effects of vision and amount

of practice on accuracy and kinematic of dart throwing. 20 female students of righthanded

who were all novitiate in the skill selected voluntarily and randomly

assigned to full vision and No-vision groups.The subjects following participated in

pretest, performed acquisition phase that consisted two level of modest and

extensive practice (45 trials and 300 trials). 10 minutes after each level of practice,

participants completed transfer trials in a no-vision and no-KR condition. Overall,

Mixed ANOVA (2×3) in acquisition phase revealed that vision improved Dart

throwing accuracy performance. Kinematic analysis revealed no significant

difference between two groups in Wrist flexion, Angular displacement of elbow and

Angular displacement of shoulder. Whereas after 300 trials of practice, there was

significant difference between groups in throwing time and angular velocity of the

dart. After extensive practice, Mixed ANOVA (2×2) showed that, withdrawal of

vision resulted in specificity of practice effects on dart throwing accuracy, but

results of kinematic pattern, regardless of the amount of practice did not support

specificity of practice.