فهرست مطالب hadis kavianipoor

The present study aimed to develop a model of the relationship between trait anxiety and the components of attentional styles in athlete students.

The current research strategy was descriptive and correlational, with the approach of developing a correlational model. In three stages, the attentional styles questionnaire was translated into Persian and was evaluated psychometrically. Its process consisted of the French version translation into Persian, re-translation into French, and the final translation. In this study, 245 athletes were selected conveniently from the student population of Shahid Beheshti University. Participants completed attentional styles and trait anxiety questionnaires. Data were analyzed using Confirmatory Factor Analysis, Cronbach's alpha coefficient, and Structural Equation Modeling (SEM).

Cronbach's alpha coefficient for two factors of top-down and bottom-up attention was 0.70 and 0.72, respectively. The confirmatory factor analysis results showed that the factor loadings of five items (items 2 and 4 of the top-down attention factor, and items 3, 8, and 9 of the bottom-up attention factor) were less than 0.4, so they were removed. SEM results showed that trait anxiety has an inverse and significant relationship with top-down attention and a direct and significant relationship with bottom-up attention.

The results of the present study highlighted the importance and necessity of paying attention to the relationship between trait anxiety and the components of attentional styles in athletes. Therefore, in planning training programs and improving sports performance, taking this relationship into account can be an effective step in preventing adverse outcomes in sports competitions.

The purpose of present study was to determine the effect of different levels of balance task difficulty and visual feedback on EMG activity of selected muscles in elderly women.

Fourteen healthy elderly women )mean age 57/65 yr( were voluntarily selected. The task consisted of performing balance task on Biodex Balance System. Participants were asked to stand still on a stability platform under two conditions (with and without visual feedback) in three levels of difficulty (6, 8 &10). Megawin EMG system was used for recording electromyography of rectus femoris, gastrocnemius, preroneus longus and biceps femoris muscles and RMS of EMG signals was obtained. Duration of each test was 20 seconds and rest times were 20 seconds.

Results showed that with increasing task difficulty, preroneus longus (p= 0/01), biceps femoris (p= 0/028), rectus femoris (p< 0/001) and gastrocnemius (p= 0/01) EMG activity increased significantly. In addition, there was a significant increase in preroneus longus (p= 0/01), biceps femoris (p< 0/001) and rectus femoris (p< 0/001) EMG activity in visual feedback condition compared with without feedback condition.

As task difficulty increased and with visual feedback, the elderly did not choose between two postural strategies but tend to combine movements in continuous behavior and they use the body stiffness strategy to improve balance.