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The purpose of the present study was to investigate Effect of self-regulation from biofeedback exercises on the learning of dart throwing skill under pressure conditions. Participants were 28 undergraduate male students of the University of Tehran who were selected in an accessible manner as they were right-handed and had no experience in dart throwing and working with biofeedback devices. These numbers were randomly divided into four groups of visual, auditory, combined and control biofeedback. The number of biofeedback training sessions was 4 sessions with pre-test, post-test and retention sessions in 4 weeks. The results of analysis of covariance and mixed analysis of variance with repeated measures showed that visual, auditory and combined biofeedback training had a significant effect on the learning of dart throwing skills under pressure (P <0/05). According to the research findings, it is suggested to use biofeedback of temperature and galvanic response of the skin, visually, audibly or in combination, to learn darts throwing skills and skills similar to and close to darts throwing skills, as well as feedback of biofeedback sessions. Prioritize the combination biofeedback to see the best results.

 

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Background and purpose: This study was conducted to determine Relationship between participation motivation and Social – Economic Status of youth in Tehran. Method: This study was cross-sectional and done by questionnaire. The analyses were based on data that collected from sports clubs in four Tehran regions (North, South, East and West), (n= 130) young people (65 male, 65 female) were selected randomly and completed the participation motivation questionnaire (PMQ) and socioeconomic status questionnaire. Result: results of Pearson’s correlation showed that there was a significant positive relationship between motivational component subscales of participation motivation in sport and socioeconomic status in young people (p ≤ 0.05). Conclusion: The present study determined there was a significant relationship between income statues, economic-class, parents’ education level and sport participation motivation.  The finding revealed that the families with high-and middle- economic class and income have a greater incentive to engage in physical activity. The education level of parents, especially fathers play an important role in encouraging their children to participate in physical activities.

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People need coordination to accomplish joint tasks and pursue the same goal. The aim of this study was to investigate the predictive mechanisms in interpersonal coordination among elite rope jumping players. The research strategy was descriptive and applied and the statistical community consisted of 24 elite rope jumping players (14 to 18 years old). Subjects practiced various rope jumping tasks (individual and joint rope jumping at the same or different distances with online landing) for eight weeks until they could do them properly and without online feedback. The researcher used a Vicon motion analysis device to record three-dimensional movements of players' feet and ropes whirling and examined spatial and temporal parameters. The results of independent t-test, repeated measures ANOVA and one-way ANOVA showed that people were similar each other in movement onset time, hand-foot deviation time, timing variation in rope whirling, and landing position (P> 0.05), while a significant difference was observed in their jump height and movement time. So, players simulate each other's movements to coordinate with each other in different tasks, and their efforts distribution doesn't related to task characteristics. In fact increasing difficulty as well demand of joint task, amount of interpersonal coordination and consequently prediction ability will increase.