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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.

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The aim of this study was to investigate simultaneous changes in EMG pattern during learning dart skill in dominant and non-dominant hands. The samples consisted of 10 non-athlete students with an average age of 23±2.5, which were divided into two group dominant hand (5) and non-dominant hand (5). Repeated measures ANOVA were used to measure data at the execution level and changes in EMG activity. The results showed a significant decrease in the absolute error of dart throwing at the performance level and an increase in EMG activity at the muscle level along with a decrease in muscle co-contraction in the acquisition and retention stages in both groups (P<.05). Also, there was no significant difference between EMG activity in the dominant and non-dominant hand groups after skill acquisition (P>.05). Generally, the results of this study showed that along with relatively constant changes in performance during dart skill learning, relatively constant changes in EMG patterns also occur, so that the concept of motor learning is also observed at the muscle level. Also, the results of this study supported the existence of the same motor program for dominant and non-dominant hand control, even in the conditions of bilateral transfer control.

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The purpose of present study was to investigate the role of motor learning strategies (linear, non-linear, and differential) in the experience of flow and clutch in beginner footballers. Participants (66, M age= 27.49 and SD =2.68) participated in this study voluntarily and based on inclusion and exclusion criteria. Participants practiced in three groups: linear, nonlinear, and differential, for three months, two sessions each week and each session one and a half hours. The study method was quantitative and qualitative. In the quantitative part, flow and clutch questionnaire was used and in the qualitative part a semi-structured interview was used. The results of Tukey showed nonlinear pedagogy was effective in flow experience and linear method in clutch experience (p<0.05). In the differential learning, flow was experienced more than linear method (p<0.05) and less than non-linear method (p>0.05). In the qualitative part, four factors of purpose, pleasure, effort and exploration are identified that support the results of the quantitative part. Based on the results of this study, nonlinear and differential methods are effective in the flow experience and linear method are effective in the clutch experience.

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Using auditory concurrent feedback with the goal of gaze path learning is one of the novelty methods in the attention field. The present study aimed to determine the effect of bisensory feedback using eye movement sonification on the decision-making of the badminton clear shot direction. In a Semi experimental strategy, with pre-post design without a control group and clinical method, participants performed recognizing the direction of the shot under unisensory and bisensory training conditions. Response accuracy, response time, and fixation duration were measured in the pre-test, immediate retention, and delayed retention. The results showed that in the immediate and delayed retention, the bisensory group had higher response accuracy and shorter response time than the unisensory group. The bisensory group had a longer fixation duration in key areas than the unisensory group in both times. The use of auditory feedback can probably be considered as a way to improve decision-making skills at the novice level.

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The aim of this study was to compare the effect of training type (full-error and error-less) and skill level on the development of mental representation of putt golf skill. For this purpose, 44 undergraduate physical education students (22 women, 22 men; mean age 22.34 and standard deviation 4.37) were randomly divided into two groups: error-less (near-to-far) and full-error (far-to-near). The two groups practiced in the one-day acquisition phase of 3 blocks of 10 attempts for throwing distances (25, 50, 75, 100, 125, 150 and 200 cm). The error-less group started training from the closest distance to the goal and reached the farthest distance, respectively, but the full-error group started training from the farthest distance and finally reached the closest distance. At the end, they were tested immediately. One day after the acquisition phase, delayed retention tests, single task transfer (from a distance of 225 cm) and dual task transfer (from a distance of 200 cm simultaneously with audio playback) were performed. To compare the effect of error-less and full-error training on the acquisition, retention and transfer of putt golf skills, data analysis of the acquisition stage was analyzed by repeated measures analysis of variance (2×8). SDA-M test was used to measure the structure of mental representations formed in the two groups before and after the acquisition period, and hierarchical cluster analysis  0.05) was used to analyze the mental representations.  Our Findings showed significant functional changes in the post-exercise mental representation structure, suggesting that motor skills are associated with functional adaptation of action-related knowledge in long-term memory.

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Video feedback is a type of augmented feedback that includes showing an athlete or performing a skill with a video clip of oneself or another person performing a particular skill. The aim of the present study was to determine the effectiveness of dyad training with video feedback on learning crawl swimming. For this purpose, 24 male students ranging in age from 11 to 17 years, who had no previous experience in learning crawl swimming, formed two groups of 12 people in dual practice and dyad training with video feedback. Both groups were first justified by the instructor, then in the double exercise group, one of the trainees entered the water and the other watched him perform out of the water, and after trying, they reviewed the mistakes and movements with their friend. in the dyad rehearsal group, one of the friends filmed another performance and showed it to him. The training intervention lasted for 8 sessions and 10 training attempts in each session. After the end of the eighth session, the 10-meter breast crawl swimming acquisition test was performed, and then a reminder test was performed again one week later and filmed. The results showed that the two groups had significant differences in both acquisition and retention, and the dyad training group with video feedback performed better overall. Based on the results, it can be concluded that the dyad training with video feedback method, in addition to being cost-effective in terms of energy consumption and training space, is also more effective than dyad training in swimming training.

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The purpose of this study was to investigate the effect of practice variability in physical compared with observational practice on golf putting performance. To this end, 50 male right-handed students (25±3.7 years) of the Ferdowsi University of Mashhad participated in this study. Participants were randomly divided into 5 groups (physical constant, physical variable, observational constant, observational variable, and control). During acquisition, the physical variable group randomly performed 50 trials from 5 different starting points to 2 different targets, but the physical constant group performed 50 trials from one starting point to one predetermined target. The observational variable and constant groups observed the performance of the physical variable and constant groups, respectively. The control group just participated in pre-and post-tests and did not practice any trial. Participants performed a test just like the pre-test 10 minutes and also 24 hours after practice. Putting accuracy was measured as the dependent measure. Results showed that variability of practice had a positive effect on participants’ performance than constant practice in physical and observational conditions (all P<0.05). Maybe the similar underlying mechanisms and also the similar feedback effects resulted in the higher performance of the variable group than the constant group in physical performance and action observation.

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Coaching is a dynamic and multidimensional process that involves the interaction between the coach, the athlete, the environment and the task, in order to enhance the athlete's performance. Based on the evidence, the coaching method can affect the behavioral aspects of the athlete. In this study, the effectiveness of student-based and coach-based coaching styles on sport self-efficacy and athletic performance of female gymnasts was studied. The research method was quasi-experimental and a pre-test-post-test design was used. The statistical population was female semi-professional gymnasts aged 11-14 in Tehran. The sampling method is one-stage cluster and the research sample was 40 female gymnasts. Variable assessment tools included Sport Self-Efficacy Questionnaire and a researcher-made sports performance Checklist. After the pre-test, the groups performed the athlete- based and coach- based exercises protocol separately for two months and two days a week in one-and-a-half-hour sessions. Covariance analysis was used to test the hypothese. Findings in the post-test stage showed that sport self-efficacy (P <0.001) and athletic performance (P <0.001) of female gymnasts in the student-based group were significantly higher than the coach-based group. It is concluded that student-based exercises style is more effective in increasing Gymnasts' sports self-efficacy and athletic performance compared to coach-based, and coaches are suggested to pay special attention to student-centered exercises in the training program for semi-professional gymnasts.

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The aim of this study was to investigate the effect of a pilates exercise period on public health and anxiety in young women during the coronavirus quarantine. This research was a semi-experimental with pre-test and post-test design and control group. For this purpose, 50 girls were randomly divided into experimental and control groups. The experimental group practiced Pilates online for 3 sessions per week at home and the control group did not receive any intervention during this period. Dependent variables were measured using the Public Health Questionnaire the Coronavirus Anxiety Scale. The results of MIX showed that Pilates exercises during quarantine had a positive effect on public health and anxiety of young women in the experimental group compared to the control group, so that probably 31% of changes in public health and 68% of changes in anxiety were affected by their pilates exercise. Therefore, based on the findings of this study, it can be concluded that Pilates improves public health and anxiety in young women, and since physical activity is an important motivational force to overcome the disease, it is necessary measures to take advantage of it.

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The effect of relative and chronological ages on the motor abilities of 7 to 12 year old students
Abstract
The aim of this study was to investigate the effect of relative and chronological age on the motor abilities of students aged 7-12 years. 600 male and female students were selected in three age categories: 7-8 years, 9-10 years, and 11-12 years. To determine the relative age, the date of birth was collected. Then, the months of their birth were determined and it was converted into months and years. The motor ability test was used to assess motor ability. Results showed that the chronological age was significant for the variable of motor abilities. Also, the relative age was significant for the variable of motor abilities. Comparison of means showed that the students born in the first and second quarters have a higher mean motor ability than students born in the third and fourth quarters. Also, students born in the fourth quarter have the lowest average motor ability. Results showed that the relative age on chronological age was significant. Therefore, female students for each of the age groups in the first and second quarters of the year have the highest score of motor ability, and female students in the age groups of 7-8 years, 9-10 years.
Keywords: Relative age, Students, Motor Ability, Chronological Age

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One of the most important issues for the elderly is the issue of physical health and cognitive problems. The aim of this study was to compare the activity of dual resistance-cognitive task with different intensities on fatigue, balance and cognitive function of elderly women. The present study is an applied and quasi-experimental method with the presence of 20 elderly women aged 60 to 70 years, which was done as a one-session test and getting answers. Subjects performed exhausting tests of foot press with machine and shoulder press with dumbbell with combined cognitive load with two different intensities (70% 1RM with low cognitive load and 30% 1RM with high cognitive load) in two days with an interval of 48 hours and the results were recorded. Balance test, upper and lower torso muscle activity and Stroop test were measured. The results of fatigue time, cognitive test and balance were significantly different between the two intensities (p <0.05). But in relation to the middle spectrum of muscle frequency, no significant difference was observed between the two intensities (p> 0.05).  Using low-intensity, high-cognitive exercise is more effective in treating upper body fatigue, which puts more pressure, which may need further investigation to evaluate the long-term success of these programs.

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The aim of the present study was to investigate the effect of auditory focus with high and low cognitive load on adolescent sports performance and working memory. The present study was conducted quasi-experimentally and Its statistical population included adolescent primary and secondary school students in Koohnani. The statistical sample was 20 students with an age range of 11-13 years. Participants were randomly divided into two groups of auditory attention focus with high and low cognitive load and in the pre-test performed working memory task with N-BACK software and 6 football chip hits towards the target. The acquisition stage was performed in 4 days.. 7 days after the final acquisition session, N-BACK working memory test, delay retention and transfer test  were taken from the participants. The results of combined analysis of variance test with repeated measures showed that the effect of auditory focus with high cognitive load on sports performance and working memory was significant (p <0.05) and the other group showed improvement only in working memory (p <0.05). Based on the results of the present, cognitive load manipulation affects work memory and athletic performance.

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 So far, there has been a lot of scattered research on various aspects of the benefits of physical activity for women in various disciplines, but there has been no coherent analysis and theorizing. Therefore, the aim of the present study was to identify, categorize and examine the types of benefits of physical activity for Iranian women at different stages of life and to theorize about the process and impact of experiencing the benefits of physical activity on primary motivations. The research method was Grounded Theory, systematic approach. Sampling was theoretical. Data analysis was performed through continuous "questioning" and "comparison". In-order-to achieve saturation while reviewing specialized texts, semi-structured interviews were conducted with 136 Iranian-women aged 7-78 who were regularly participate in physical-activity in addition to 17 mothers and 6 fathers. The findings of the present study show that the benefits of physical activity for Iranian women can be classified into six general categories: (1) "health development", (2) "motor development", (3) "socio-behavioral development", (4) "enrichment of leisure time", (5) "Beauty" and (6) "Prevention and Treatment". Findings also showed that experiencing the benefits of physical activity strongly influences the modulation of initial motivations and the formation of strong and lasting motivations. According to the research findings; Cultural-sports managers should include all the important benefits of physical activity experienced by women at different stages of life in the content of Iranian women's physical activity promotion programs and do not suffice to provide general and specialized intangible content.

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This study aimed to investigate the effectiveness of basic taekwondo exercises on the executive functions of children with a learning disorder. For this purpose, 20 boys aged 10 to 12 years with learning disorder in Mashhad were selected and randomly assigned to training and control groups. The training group practiced Taekwondo for 12 sessions, each session lasting 50 minutes, repeating three days a week. The control group also engaged in their normal daily activities during this period. Changes in subjects' cognitive functions were measured before and after the training period by the N-back and the Tower of London tests. Analysis of variance with repeated measures was used for statistical analysis. The results showed that basic taekwondo exercises improve executive functions in the training group; All these changes were significant compared to the control group (p<0/05). Therefore, based on the results of the present study, it can be concluded that basic taekwondo exercises help to improve the executive functions of children with learning disorder by affecting brain areas related to executive functions.
 

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Our understanding of the effectiveness of small-sided games compared to other training methods is limited. Therefore, the aim of this study was to compare the role of small side games (SSG) and traditional teaching method on individual and team creativity of 11-12 year old soccer players. To conduct this study, among all the 11-12-year-old children of Iraq who were enrolled in football classes, 30 learners were selected by the available method and were randomly divided into two groups of traditional and SSG education. At first, the pre-test was taken by the video analysis method, and then the participants practiced football skills on the 7x7 field for 16 weeks and 4 one-hour sessions every week. Finally, the post-test was evaluated according to the pre-test. The analysis of the film was done based on the opinion of two experts and according to the previously identified practices. The results were analyzed by descriptive method and 2x2 ANOVA analysis in SPSS 24. The results of the study in the descriptive part showed that appropriate actions, creative and original actions have grown more in the SSG group compared to the traditional group. In this regard, inappropriate actions have shown a further decrease. In the section of inferential tests, the results showed that the effect of the test and test*group is significant for appropriate actions and the effect of the test for total actions showed the same result. In this regard, small side games can be played by placing the player in a small environment, allowing the player to have more opportunities to perform and less time to make decisions, which leads to the improvement of creativity in team sports such as football.
 

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The present study aims to investigate the variables of social networks in different positions in basketball. These variables were applied in two levels of analysis: micro (individual) and macro (global interaction of the team). 24 official Chemidoor Club competitions in the 2020 men's Iranian Premier League were selected by available sampling. This research analyzed the network properties of Degree, Betweenness, Closeness, Eigenvector, and Density centrality across teams and positions. The one-way ANOVA for the factor position in the micro-level found statistical differences between the game positions in the dependent variables of  Dc: (F(4,15)= 61/29, p= 0/000), Bc: (F(4,15)= 210/11, p= 0/000), Cc: (F(4,15)= 78/55, p= 0/000). However, no significant difference was observed in the Eig: (F (4, 15) = 1/58, p= 0/184). Results of post hoc test indices were significantly different between position 1 (point guard) and other positions.  Macro-level team density analysis showed a significant difference between performance results in successful and unsuccessful. The guard player role was observed as the situation that establishes the most interactions with teammates during the competition. Therefore, players with higher degrees were not the ones assisting the most shots. The other players with higher degrees were not the ones assisting the most shots. These results may be used as a tool for coaching to improve their teams’ strategies in concrete, measurable ways.
 

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The literature on self-controlled motor learning includes efforts that compare a group of learners who have choices about some aspect of their practice environment with a group who are dependent on those choices. Therefore, several studies have shown that self-control practices have benefits. In the present study, using the self-control approach, the choice order during golf practices, the level of skill accuracy, autonomy, and self-efficacy were investigated. The present research is of a semi-experimental type and was carried out during the 24-hour follow-up period. Twenty-four beginner students were available and randomly placed in the experimental group (n=12) or yoked group (n=12). In the pre-test, the participants took the golf putting test. Then the yoked group used the practicum devices in the order of choice of the experimental group. On the first day, skill accuracy, autonomy, and self-efficacy were measured in the pre-test and acquisition, and then with the retention test. The results of the repeated Measurements analysis test showed that self-control has a significant effect on golf putting skill, autonomy, and self-efficacy. Therefore, a small choice such as the order of practice in the self-control approach can be effective on motor performance and learning, and the psychological components related to them.
 

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The aim of the present study was to investigate the effect of inducing positive stereotypes on perceived competence, interest and motor learning in adolescent girls. Therefore, among all of the adolescent girls in Shiraz, 30 adolescent with the age range of 10-13 years were selected by convenience sampling. Participants performed 10 trials as a pre-test and afterward, they were randomly divided into two groups  . The acquisition phase consisted of 50 trials (5 blocks of 10 trials), and the task required participants to perform inside kicks at targets area attached to a wall and touching the ground. Twenty-four hours after the acquisition phase, participants attended retention test (with 10 trials) to check learning effects on them. The participants were asked to answer the questions related to perceived competence and interest before pre-test, after the acquisition phase, and before the retention test. To analyzing data, one way and Mix ANOVAs analysis and Independent T test were conducted using SPSS21 at significance level P≤0.05. The results showed that in the acquisition phase, all groups significantly increased their accuracy, though difference among groups was not significant. Also, the results showed that the induction of positive stereotypes led to higher perceived competence and motor learning in adolescent girls

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The aim of this study was to comparison of the effectiveness of linear and non-linear pedagogy on locomotor motor skills Performance and movement motivation in children with developmental coordination disorder. The statistical population was all children with developmental coordination disorder in Urmia. The statistical sample consisted of 30 boys (age = 9.35 ± 1.37) who were selected from Urmia schools using the available method. MABC-2 test was used to diagnose developmental coordination disorder, TGMD- test was used to evaluate locomotor skills, and motor motivation test was used to evaluate movement motivation. To carry out this study, the participants practiced two 50-minute sessions of motor skills interventions in two linear methods (15 people) and task manipulation (15 people) for eight weeks. Variables were measured before and after the interventions. The results of covariance analysis showed that non-linear training compared to linear training significantly improved both in movement skills (p=0.04) and motor motivation (p=0.000) than the linear group. According to these results, non-linear methods considering the individual characteristics of each child are helpful for helping children with movement disorders. Considering the unique characteristics of each child helps to improve motor skills and to have enough motivation to continue the activity. Therefore, the use of non-linear methods is suggested for children with developmental coordination disorder.