Motor Development and Learning
Behzad Mohammadi Orangi; mehdi shahbazi; behnaz bakhshinezhad
Abstract
Introduction: The aim of this study was to compare linear, nonlinear, and differential and TGFU methods on individual and team creativity and decision-making in combination with inclusive education.
Methods: To achieve this goal, 64 male children (10.22±1.73) were selected as available samples. For ...
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Introduction: The aim of this study was to compare linear, nonlinear, and differential and TGFU methods on individual and team creativity and decision-making in combination with inclusive education.
Methods: To achieve this goal, 64 male children (10.22±1.73) were selected as available samples. For two months, children practiced futsal skills two sessions every week and each session lasted 90 minutes in four groups (12 normal children, two hyperactive children and two DCD children in each group). The number of observed actions was recorded and analyzed for each variable: individual creativity, team creativity, and decision-making creativity. Part of the data was analyzed descriptively and the rest with 2 (time)*4 (group) ANOVA test.
Results: The results of this study indicate that the linear method has less impact on individual, team, and decision-making creativity compared to the nonlinear, TGFU, and differential methods. The nonlinear group outperformed the others in original and creative actions, team creativity, and decision-making. In the inclusive education section, individuals with disabilities showed better performance in post-tests for creative actions, original actions, team creativity, and decision-making in the nonlinear, differential, and TGFU groups compared to the linear method.
Conclusion: The results of this study emphasize the importance of integrating inclusive education with non-linear methods, in which the manipulation of constraints can cover the weaknesses of children with problems. These results can be used in schools.
Mehdi Rahim zadeh; Shahzad Tahmasebi; Mehdi Shahbazi
Abstract
Background: In previous studies, the effect of arousal on performance has been investigated. However, whether arousal during learning stages affects bimanual coordination has not been investigated. Therefore, the present research aimed to investigate the effect of arousal levels during different learning ...
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Background: In previous studies, the effect of arousal on performance has been investigated. However, whether arousal during learning stages affects bimanual coordination has not been investigated. Therefore, the present research aimed to investigate the effect of arousal levels during different learning stages on the performance of the hand-eye coordination task.Methods: For this purpose, 36 male physical education students aged 20-35 were conveniently selected and based on normal IQ, normal trait anxiety, and right-handedness, were matched into three Low Arousal, Normal Arousal, and High Arousal groups. The study involved pre-test, post-test, retention, and transfer stages. In the pre-test stage, the participants performed 10 trials of the eye-hand coordination task. The training period consisted of 10 sessions and 50 trials per session, in which at the end of each session 10 trials were recorded as performance. The retention and transfer tests were performed 24 hours after the last training session. The data were analyzed using repeated measure analysis of variance, one-way analysis of variance, and Tukey's post hoc tests.Results: The results of the present study showed that high, normal, and low arousal levels have a significant effect on the duration of the eye-hand coordination task during the cognitive, association, and automatic stages, and also the time of the eye-hand coordination task was improved.Conclusion: According to the results of the study, it is suggested that educators use these arousal stimulation effects to improve the performance and learning of athletes in pursuit tasks.
Mohammadali Esmaeilzadeh; Mehdi Shahbazi; Ali Akbar Jaberimoghaddam; Shahzad Tahmasebi; Elham Shirzad
Abstract
Behavioral studies in team sports are typically constrained by dynamic factors, such as positioning of defenders for interception. Handball player have to coordinate their steps when running to throw a ball on goal from a different positions. In this study were analyzed the movement patterns during locomotors ...
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Behavioral studies in team sports are typically constrained by dynamic factors, such as positioning of defenders for interception. Handball player have to coordinate their steps when running to throw a ball on goal from a different positions. In this study were analyzed the movement patterns during locomotors pointing, throwing velocity and accuracy of 12 succesful elite handball players under defensive constraints (defender- absent, defender-far, defender-near, or defender pairing). It was captured data from the locomotors patterns of the attacking participant by speed camera with 120Hz, throwing speed by sports radar gun and throwing accuracy by camera. ANOVA with repeated measures and Bonferroni post hoc test and Friedman test was used to analyze effects of these constraints on gait and throwing parameters. In addition to Pearson and Spearman correlation coefficient test was used to analyze speed-accuracy trade off (P<0.05). The results revealed significant differences in overall mean movement velocity, first and second step mean velocity, first and second step mean length. For the mean foot/gate area distance variability was shown pattern of ascending/descending variability in all defense conditions. Since regulation of offensive players was continuous and based on perception of current and required behaviors, results supported from perception-action coupling and prospective control models of locomotors pointing. Also it is suggested that the technical aspects of the running and throwing in handball can affect by nested tasks constraints.
Mohammad Bagher Aali; Mehdi Shahbazi; – Mohammad Sohbatiha
Abstract
Self-talk is one of the psychological factors influencing the improvement and success of motor performance. The present research aimed to investigate the effect of motivational self-talk on bimanual coordination of university students. 24 students of physical education (12 females and 12 males, mean ...
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Self-talk is one of the psychological factors influencing the improvement and success of motor performance. The present research aimed to investigate the effect of motivational self-talk on bimanual coordination of university students. 24 students of physical education (12 females and 12 males, mean age = 22.62 and SD = 2.081) were selected by convenience sampling method. After the pretest, subjects were divided into two homogeneous groups of motivational self-talk and no self-talk using bimanual coordination tester. For data analysis, descriptive and inferential statistics including independent t test and paired t test were used at 0.05 significance level. Results showed that self-talk improved the coordination performance significantly (p < 0.05). Also, the female group had a significantly better precision in bimanual coordination (p < 0.05) and the male group had a significantly better speed in bimanual coordination (p < 0.05). But, there was a significant difference between boys and girls in self-talk group in the posttest (p < 0.05). According to these findings, it is suggested that motivational self-talk should be used to improve and promote bimanual coordination performance.
Negin Nazarifar; shahzad Tahmasebi; Mehdi Shahbazi
Abstract
Cognitive constrain of individual constrains which can be created with imagery and is a factor in many tasks affecting the performance has been investigated. Thus, the aim of the present study was to investigate the effect of PETTLEP imagery on the accuracy and speed basketball pass skill. 44 female ...
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Cognitive constrain of individual constrains which can be created with imagery and is a factor in many tasks affecting the performance has been investigated. Thus, the aim of the present study was to investigate the effect of PETTLEP imagery on the accuracy and speed basketball pass skill. 44 female students of Faculty of Physical Education, University of Tehran (mean age of 22.45±2.3 years) were selected by convenience sampling method and participated in this study. In pretest, participants performed 2 blocks of 10 trials of accuracy and speed basketball pass. Then, they were assigned to one of the four groups homogeneously: accuracy pass PETTLEP imagery, speed pass PETTLEP imagery, accuracy control, and speed control. Two groups of imagery listened to the imagery audio during 3 days for 8 minutes per day. Then, subjects participated in posttest, retention and transfer tests. For data analysis, mixed ANOVA was used. In case of significance, independent t test was used for intergroup comparisons and analysis of variance with repeated measures was used for within-group comparisons with significance level of α=0.05. The results of analysis of variance indicated no significant differences between imagery and control groups in pretest. However, there were significant differences in posttest, retention and transfer tests between imagery and control groups (P≤0.05). Also, PETTLEP imagery of accuracy and speed pass improved accuracy and speed pass performance from pretest to retention test; however, there was no such process in transfer test (P≥0.05).
Leila Ghandehari Alavijeh; Shahzad Tahmasebi Boroujeni; Mehdi Shahbazi
Abstract
Theoretically, skill presentation will change behavior through processes such as imitation and motor repetition. If we want learning to happen, we need a process called training. Training can be delivered by the instructor through verbal and non–verbal instructions to the learner. One type of non–verbal ...
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Theoretically, skill presentation will change behavior through processes such as imitation and motor repetition. If we want learning to happen, we need a process called training. Training can be delivered by the instructor through verbal and non–verbal instructions to the learner. One type of non–verbal instruction is pattern representation in which learner can learn through observation. The purpose of this model is to use the pattern representation as a means of transmitting information. Thus, the aim of this study was to evaluate the effect of three training methods: immediate, interspersed and combined imitation on Juno kata form performance. Therefore, 45 girls (9-12 years old) in Tehran city voluntarily participated in this study and were divided into three groups (each group 15 subjects) based on the type of intervention. Groups of immediate, interspersed and combined imitation had special imitation training programs with specific repetitions. In order to quantify data, 10-point Kata scale was used. As the data distribution and variance homogeneity were obtained, the result of analysis of variance with repeated measures showed that all three observational methods helped to improve the performance and this progress remained stable in the retention and transfer tests (P≤0.05). Also, the results of multivariate analysis of variance showed the priority of immediate imitation group on interspersed (P=0.0005) and combined (P=0.0005) imitation groups. The combined imitation group gained better scores than interspersed group (P=0.0005) and this differences was stable in retention and transfer tests.
Faranak Poorhosseini; Mehdi Shahbazi; Shahzad Tahmasebi Boroujeni
Abstract
The aim of this study was to investigate the emergence of special skill in basketball free throw at different skill levels based on Newell's model of learning stages. Participants were assigned to three skill groups (n=10): coordination group, coordination control group, and optimization group. They ...
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The aim of this study was to investigate the emergence of special skill in basketball free throw at different skill levels based on Newell's model of learning stages. Participants were assigned to three skill groups (n=10): coordination group, coordination control group, and optimization group. They threw 350 fixed shots from 7 parametric points (2.74, 3.35, 3.96, 4.57, 5.18, 5.79, 6.4), carrying out 50 shots in each point. Regression analysis showed that the accuracy of those who were in the third stage of Newell's model in 4.57 m point, which is the same line of penalty, was significantly higher than the anticipated regression equation and supported the emergence of special skill (P>0.05), but the rest of the points did not follow the principles of force variability and performance accuracy decreased by increasing distance parameter. Moreover, multiple regression analysis showed that the rest of the points had no contribution to the emergence of special skill and this conclusion may be the reason for rejecting generalized theory in the creation of special skill.
Akbar Bohloul; Mehdi Shahbazi; Shahzad Tahmasebi Boroujeni
Abstract
Coordination is an important part of successful movements in daily life and sports. The aim of this study was to investigate the effect of different levels of cognitive activities on intrapersonal and interpersonal motor coordination in taekwondo athletes (Poomsae). The population consisted of Poomsae ...
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Coordination is an important part of successful movements in daily life and sports. The aim of this study was to investigate the effect of different levels of cognitive activities on intrapersonal and interpersonal motor coordination in taekwondo athletes (Poomsae). The population consisted of Poomsae male athletes in Tehran city. 30 individual Poomsae athletes and 30 team Poomsae athletes (age range: 17 - 30 years old) were selected by convenience sampling method. The sample was divided into 3 groups: control, easy cognitive activities and difficult cognitive activities. The control group only performed the motor coordination task whereas the cognitive groups performed the dual task. The results of one-way ANOVA test showed a significant difference for two handed (P=0.003) and two legged (P=0.04) coordination in total time factor (speed). Also, there was a significant difference in the error percentage factor for interpersonal motor coordination (P=0.02). In a two by two group analysis, the easy (P=0.003) and difficult (P=0.001) cognitive activities groups in two handed motor coordination and the difficult cognitive activities group in two legged (P=0.02) and interpersonal (P=0.01) motor coordination performed better than the control group. It is suggested that difficult activities should be used in addition to regular physical activities.
Sajjad Tarshizi Bargoei; Mehdi Shahbazi; Abuzar Darabi
Abstract
The present study aimed at investigating the effect of rich environment athome on the speed of acquisition progress in football dribbling skill of boys.The statistical population included children aged between 6 and 13 in district1, Tehran city. The present study was semi-experimental with pretestposttestdesign. ...
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The present study aimed at investigating the effect of rich environment athome on the speed of acquisition progress in football dribbling skill of boys.The statistical population included children aged between 6 and 13 in district1, Tehran city. The present study was semi-experimental with pretestposttestdesign. Based on the results of the distributed questionnaires, 30subjects were selected as the sample and were divided into two groups: richand non-rich. Firstly, both groups participated in football dribbling test as thepretest. Then, both rich and non-rich groups received training for 9 days andone session per day. At the end of each training session, both groupscompleted football dribbling test again. To compare the groups, the 2 × 9mixed analysis of covariance was used, and dependent t test was applied toexamine intragroup changes. Wilks Lambda index indicated that the effect ofenvironment on the speed of learning progress was significant(F(9&19)=3.27), P<0.014, correlation ratio=0.608). The rich group had ahigher speed of learning progress than the non-rich group. The comparisonof the training days of both groups showed that the rich group wassignificantly better than the non-rich group for all days except for day 4. Theresults of dependent t test showed a significant difference between pretestand day 9 in rich (P<0.001) and non-rich (P<0.001) groups. Overall, theseresults show that enriched home environment significantly improves thespeed of learning progress.
Bahram Ghafari; Mehdi Shahbazi; Mehdi Aghapour; Elham Shirzad
Abstract
Meta-stability is a relatively stable region in which system components tend to cooperate to reach performance goals of movement while maintaining their separate and flexible characters. Participants were assigned to 3 skill groups: coordination (n=10), coordination control (n=10), and optimized ...
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Meta-stability is a relatively stable region in which system components tend to cooperate to reach performance goals of movement while maintaining their separate and flexible characters. Participants were assigned to 3 skill groups: coordination (n=10), coordination control (n=10), and optimized control (n=10). Each two fencers fought in each group. Results of cluster analysis and empirical density indicated the emergence of a metastable region in coordination control group (between 1.689276- 2.270372), two metastable regions in optimized control group (between 0.9824658- 1.00113699 and 1.843131-2.333738) and no metastable region in coordination group. Moreover, the binomial test showed that the proportion of using modes of actions in metastable regions in coordination control and optimized control groups had no significant difference (P=0.4888). But the extent of metastable region in the coordination control group was significantly greater. Findings of this study showed that fencers' motor system is metastable depending on their skill level and the extent of metastable regions was different in each level. To design learning and organizing practice, sport coaches can lead the athletes to metastable regions to emerge the most functional motor responses.
Ali Zahiri; Mehdi Shahbazi; Mohammad Reza Kordi; Jamal Fazel Kalkhoran
Abstract
The aim of this study was to investigate the effect of central and peripheral fatigue on motor coordination in collegiate athletes. The population consisted of all the students of Faculty of Physical Education and Sports Sciences of University of Tehran and 24 subjects were selected by convenience sampling ...
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The aim of this study was to investigate the effect of central and peripheral fatigue on motor coordination in collegiate athletes. The population consisted of all the students of Faculty of Physical Education and Sports Sciences of University of Tehran and 24 subjects were selected by convenience sampling method. They were randomly divided into two groups (central and peripheral fatigue) depending on the type of fatigue after a bimanual motor coordination pretest. Bimanual motor coordination posttest was performed after the intervention for 12 hours. In order to investigate the differences between the groups, independent t test and to determine differences within a group, dependent t test were used with the significance level of P≤0.05. Results showed that the mean time to complete the task and the timing error in central (P=0.004) and peripheral (P=0.0001) fatigue groups significantly increased compared with the pretest. Also, a significant difference in bimanual motor coordination between the two groups was observed in posttest (P=0.006). According to the results, it is suggested that athletes' training and working programs should be planned so that they include exercises to increase mental stamina along with physical exercises and that the athletes can provide their optimal performance in different conditions.
Reyhaneh Rahdar Beik Qomi; Mehdi Shahbazi
Abstract
Decision making plays an important role in sport activities and is directly associated with sporting success or failure. On the other hand, one of the key issues in psychology of sports and behavioral sciences is sport orientation. The aim of this study was to investigate the relationship of ...
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Decision making plays an important role in sport activities and is directly associated with sporting success or failure. On the other hand, one of the key issues in psychology of sports and behavioral sciences is sport orientation. The aim of this study was to investigate the relationship of action and state orientation with decision making behavior of expert female football players. 27 players who attended competitions for at least 8 years participated in the present study. Action Control Scale (ACS-90) was used to specify action or state orientation of players. Then, to evaluate the performance of decision making of players, the images of real football situations were used. The players were required to respond correctly to one of the existing options (shooting, dribbling, passing). K-S test was applied to examine normal data distribution and multiple regression and Pearson correlation coefficient were used to analyze data at significance level of 0.05. Results showed a significance correlation between action orientation and accuracy and decision making behavior of action players (P<0.05); however, this correlation was not significant between action orientation and speed of decision making (P>0.05). Moreover, results indicated no significant relationships between state orientation and variables (accuracy, speed and decision making behavior) of state players (P>0.05). Finally, it can be inferred that action orientation in expert players has a correlation with accuracy in decision making and risk taking choices and it can facilitate reaching their goals.
Somayeh Tabatabai; Mehdi Shahbazi; Fazlolah Bagherzadeh
Abstract
The term autistic refers to the individuals who have a set of development disorders relevant to the central nervous system. These children are known to have deficiency in social interaction, language and communication. The aim of this study was to investigate the relationship between motor development ...
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The term autistic refers to the individuals who have a set of development disorders relevant to the central nervous system. These children are known to have deficiency in social interaction, language and communication. The aim of this study was to investigate the relationship between motor development and social development of 6-10-year-old autistic children of Mashhad city. The statistical sample involved 41 students with high–functioning autism (31 boys and 10 girls). The researcher calculated the students' social development scores using SCQ questionnaire. Using Lincoln-Oseretsky Motor Development Scale, the level of motor development was determined. In descriptive section, mean and standard deviation were used and in inferential section, Pearson correlation coefficient was applied with 95% confidence level. The results showed a significant relationship between students' motor development and their social development (P<0.05). Also, there was a significant relationship between the boys' gross motor skills, fine motor skills, hand-eye coordination and their social development (P<0.05). The girls' fine motor skills and hand-eye coordination were significantly related to their social development (P<0.05), but there was no significant relationship between the agility of fingers and social development in both groups (P>0.05). These results of the relationship between motor development and social development showed that motor skills can affect the improvement of autistic students.
Bahram Ghafari; Mehdi Shahbazi
Abstract
The aim of this research was to investigate the ability of arousal control in male and female athletes using mental imagery and biofeedback methods. Participants were 30 male and female athlete students of Tehran University (mean aged 23) who were assigned into two homogeneous groups based on Vividness ...
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The aim of this research was to investigate the ability of arousal control in male and female athletes using mental imagery and biofeedback methods. Participants were 30 male and female athlete students of Tehran University (mean aged 23) who were assigned into two homogeneous groups based on Vividness of Movement Imagery Questionnaire 2. Participants were given acoustic biofeedback during three stages of pretest, posttest, and follow-up test while their scores in arousal indexes such as heart rate, body temperature, and galvanic skin response were recorded. In posttest, they were asked to mentally imagine their performance under competition circumstance and in follow-up test they had to attempt to lower their arousal level using deep breathing and acoustic biofeedback technique. Results of analysis of variance with repeated measures and independent t test indicated that there is a significant difference between groups mean scores in follow-up test in three indexes of heart rate, body temperature, and galvanic skin response (p≤0/05). This finding suggests that male students have higher ability in arousal control compared with female students.
Mehdi Shahbazi; Aboalfazl Shayan; Ali Samadi; Zahra Nemati
Abstract
There are evidences in both animal and human studies which show that exercise has beneficial effects on the central nervous system and cognition. So, the aim of this study was to investigate the effect of resistance exercise on memory and probable mechanisms of this effect (i.e. neurotrophic factors) ...
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There are evidences in both animal and human studies which show that exercise has beneficial effects on the central nervous system and cognition. So, the aim of this study was to investigate the effect of resistance exercise on memory and probable mechanisms of this effect (i.e. neurotrophic factors) in sedentary students. 30 sedentary students (mean age, 23.8±1.6 yr) were randomly divided into two groups: control and resistance. After blood sampling and memory test, they continued their exercises for 5 weeks based on the resistance training protocol. In the end, at least 48 hours after the last training session, the memory test and blood samples were collected in order to eliminate the temporary effects of exercises. For analysis of the data, Covariance test and Pearson correlation coefficient were used (P≥0.05). Results showed that resistance exercises significantly increased memory score (P<0.05). Although BDNF significantly increased after the exercises, the exercises did not influence the expression of any neurotrophic factors (P˂0.05). Furthermore, there was no significant correlation between variations of memory scores and variations of expression of neurotrophic factors (P˂0.05). The findings indicated that exercise can improve memory.
Amir Abbas Gholipoor; Mehdi Shahbazi; Fazlollah Bagherzadeh
Abstract
Attribution theory is one of the psychological dynamic theories that explainsand describes people's perception of facts. Therefore, the aim of this research wasto study success and failure attributions in athletes and coaches. The population ofthis study consisted of athletes and coaches of national ...
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Attribution theory is one of the psychological dynamic theories that explainsand describes people's perception of facts. Therefore, the aim of this research wasto study success and failure attributions in athletes and coaches. The population ofthis study consisted of athletes and coaches of national teams (elite) and clubteams (sub–elite) in swimming, badminton, karate, taekwondo, table tennis andwrestling. 120 male players and 12 coaches were selected through multistageconvenience sampling method. Then, data were collected by attribution stylesquestionnaire (ASQ). The data were analyzed by multivariate ANOVA at P˂0.05.The findings showed that elite athletes expressed more unstable and specificattributions in failure conditions. In contrast, sub–elite athletes expressed morestable and general attributions in failure conditions (P≤0.0001). As well, thecoaches of elite athletes expressed more stable and specific attributions than thecoaches of sub–elite athletes in success dimension (P≤0.0001). The results showedthat the casual attribution of athletes (elite and sub-elite) and their coaches (eliteand sub-elite) expressed elite athletes and coaches' privilege as elite athletesexpressed that most of the reasons for their success were internal, stable andgeneral. Also, athletes and coaches stated different attributions in the samesituation. It is recommended that coaches encourage their athletes to attempt moreto express all of their competencies in the competitions.
Fatemeh Rezaei; Mahdi Shahbazi; Fazollah Bagherzadeh
Abstract
Skillful performance in soccer requires not only sound techniques but also quickand accurate decision making. These decisions are usually made in variousintensities of practice and performance. The main aim of this study was toinvestigate the effect of different levels of arousal and training intensity ...
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Skillful performance in soccer requires not only sound techniques but also quickand accurate decision making. These decisions are usually made in variousintensities of practice and performance. The main aim of this study was toinvestigate the effect of different levels of arousal and training intensity on decisionmaking (speed and accuracy) of expert female soccer players. For this purpose, 16expert female soccer players (mean age 22.4±3.8 yr) with 8 or more years ofcompetitive experience were voluntarily selected from Tehran women's premierleague. Soccer related photographs on a computer monitor were used to evaluatethe decision making task; participants had to decide which action they wouldundertake (shoot, pass, dribble). Three different levels of arousal (low: with nospectators, medium: with silent spectators and high: with cheering spectators) inthree different levels of intensity (resting, 40% of HRmax, 80% of HRmax) weredesigned. To measure the accuracy and speed of decision making, parametricmethod of MANOVA, 3(training intensity levels) in 3 (arousal levels), was used. Tototally compare the groups, one-way analysis of variance, ANOVA with repeatedmeasures and Tukey post hoc test were used at α=95%. The results showed nosignificant difference in the speed of decision making among different arousallevels (P>0.05) while a significant difference was observed in the accuracy ofdecision making among different arousal levels (P˂0.05). The speed of decisionmaking improved in the low and medium arousal levels through an increase intraining intensity while no significant difference was observed in the speed ofdecision making in high arousal level among different intensity levels (P>0.05).Furthermore, the accuracy of decision making showed no significant difference inlow and high arousal levels among different intensity levels (P>0.05). Theaccuracy of decision making improved in low arousal level through an increase intraining intensity. These finding showed that training intensity and arousalseparately influenced each decision making component.
Mehdi Shahbazi; Ali Pashabadi; Hossein Abedini Parizi
Volume 3, Issue 2 , October 2012, , Pages 65-80
Abstract
Reaction time (RT) is one of the psychomotor skills that determine athletes’ results and also in daily life. RT effective factors are divided into inherent (genetic) and environmental. Among those factors, psychological factors and mental abilities are more important due to the cognitive nature of ...
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Reaction time (RT) is one of the psychomotor skills that determine athletes’ results and also in daily life. RT effective factors are divided into inherent (genetic) and environmental. Among those factors, psychological factors and mental abilities are more important due to the cognitive nature of RT. The aim of this research was to study the relationship between RT, anxiety and IQ of athletes in different skill levels. This relationship was investigated in 85 subjects (in elite and sub elite athletes and no athletes groups) by correlation method. To measure RT, Y1000 devise was used; Spielberger state / trait anxiety inventory (STAI) was used to evaluate anxiety and Raven’s progressive matrices to evaluate IQ. One-way analysis of variance and Pearson correlation coefficient were used to analyze the data. Results showed that there was a negative significant correlation between choice RT and IQ, and between CRT and state anxiety. Findings supported inverted U hypothesis and it proved the greater influence of IQ with higher complexity of task
Amir Vazinitaher; Mehdi Shahbazi; Fazlolah Bagherzadeh
Volume 3, Issue 1 , June 2011, , Pages 103-128
Abstract
Talent identification is a process through which those with the highest chance to succeed in the future will be determined. The purpose of the present study was to investigate the application of a multivariate approach in talent identification of adolescent soccer players. The research population consisted ...
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Talent identification is a process through which those with the highest chance to succeed in the future will be determined. The purpose of the present study was to investigate the application of a multivariate approach in talent identification of adolescent soccer players. The research population consisted of all soccer players in Tehran province aged between 12 and 16 years old. A battery of tests was applied to measure the psychological, technical, physiological and anthropometric factors in adolescent soccer players in two levels of elite (N=26) and sub-elite (N=35). Participants were divided into four age groups: U16, U15, U14, and U13. The OMSAT – 3 was used to evaluate the mental skills. Furthermore, technical skills were measured by six soccer skills tests of Football Association of England. Physiological measurements consisted of vertical jump, sit up, 10m sprint, 40m sprint and 280m shuttle run. Anthropometric characteristics were height, weight, body mass index, length of lower and upper leg, skin folds in four regions and body fat percentage. Statistical method to analyze the findings was MANOVA. The results showed that among four groups of factors, the physiological measures were statistically more capable of distinguishing the levels. The results of the present study showed a significant difference between elite and sub-elite soccer players in physiological, technical and psychological characteristics, but there was no significant difference in anthropometric attributes. There was a significant difference between elite and sub-elite soccer players in sit up, shuttle run, 10m sprint, 40m sprint, running with ball, turning, speed, dribbling, shooting, goal setting, relaxation, coping with stress, activation, focus, refocus and competition plan (P
Mehdi Shahbazi; Amir Vazini; Navid Hadadi
Volume 2, Issue 2 , July 2010
Abstract
The purpose of the present study was to determine the effect of increasing arousal and its effect on athletes' depth perception. Participants of this study included the students of Faculty of Physical Education and Sport Sciences. 58 students (23 female and 35 male, mean age: 23.3 and SD: 2.16) were ...
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The purpose of the present study was to determine the effect of increasing arousal and its effect on athletes' depth perception. Participants of this study included the students of Faculty of Physical Education and Sport Sciences. 58 students (23 female and 35 male, mean age: 23.3 and SD: 2.16) were selected randomly. Participants performed the study tests under two motivational conditions (with viewer and without viewer). The sport competitive anxiety test (SCAT) was performed to test the level of participants' arousal. Moreover, the instrument to test depth perception was the electrical set of depth perception (122B). Results of paired t-test showed a significant difference in scores of depth perception test between the two motivational conditions at 0.05. In other words, participants in high arousal condition (i.e. with viewer) had an inaccurate estimation of depth perception. This effect was the same in both sexes. The results of this study indicated that novice athletes in high arousal condition pay attention to different information resources or different peripheral cues which lead to inaccurate estimation of depth.
Mahmoud Sheikh; Mehdi Shahbazi; Ashraf Amini; Reza Gholamalizadeh
Volume 2, Issue 1 , April 2010, , Pages 45-56
Abstract
The aim of this research was to investigate the situation of talent identification process and to collect Karate related indexes in Iran. For this purpose, 63 karate subjects, male (N=31) and female (N=32), participated and filled in 3 special questionnaires to identify present and optimal situation ...
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The aim of this research was to investigate the situation of talent identification process and to collect Karate related indexes in Iran. For this purpose, 63 karate subjects, male (N=31) and female (N=32), participated and filled in 3 special questionnaires to identify present and optimal situation of talent identification and most important aspects of biometric, motor capabilities, psychological capacity and skill indexes. The data were analyzed by Pearson coefficient correlation (P?0.05). The results showed that although the reaction time of hand and foot, flexibility, coordination, hand and foot length, agility and sergeant jump were the most important anthropometrical factors related to successful performance, but the reaction time of hand and foot, flexibility and coordination were significant predicators of discriminating athletes. In motor capabilities, the endurance of cardiovascular system played the main role and was an important predictor. In psychological capacity, two factors of concentration and self-confidence had a critical role and only concentration was a significant predictor. The results of this study showed no pattern for talent identification in Iran from coaches and athletes’ viewpoints.
Shahzad Tahmasbi; Ahmad Farokhi; Naser Naghdi; Fazlolah Bagherzade; Anoushirvan Kazemnejad; Mehdi Shahbazi
Volume 1, Issue 2 , October 2009, , Pages 21-46
Abstract
The purpose of this study was to evaluate the effect of two regimes during rats' gestation and lactation on learning, memory and motor function of their offspring. For this purpose, female rats (Albino-Wistar) were obtained from Pasteur Institute, Iran. After mating, 12 pregnant rats were divided into ...
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The purpose of this study was to evaluate the effect of two regimes during rats' gestation and lactation on learning, memory and motor function of their offspring. For this purpose, female rats (Albino-Wistar) were obtained from Pasteur Institute, Iran. After mating, 12 pregnant rats were divided into three groups and they had their special regimes during their last week of pregnancy as well as their lactation. Control group used a standard diet, the zinc deficient (ZnD) group a diet deficient in zinc and the zinc supplement (ZnS) group a standard diet and enhanced zinc (10ppm) in their drinking water. 12 male offspring in each group were selected as the statistical sample and they were tested for learning and memory in MWM on their 56th natal day (ND) and were tested for motor activity in open-field on their 66th natal day. One-way ANOVA, post hoc Tukey test and repeated measures ANOVA were used to analyze the data (P
Mehdi Shahbazi; Mahmud Sheikh; Naser Naghdi; A Farokhi; Anoushirvan Kazem nejad; Shazad Tahmasbi
Volume 1, Issue 1 , July 2009, , Pages 5-25
Abstract
The purpose of this research was to determine the effect of two kinds of diet (zinc deficiency and iron deficiency) on some anthropometrical indexes (body weight and crown-rump length), brain growth and motor function in young rats. Adult male and female albino wistar rats were obtained from the breeding ...
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The purpose of this research was to determine the effect of two kinds of diet (zinc deficiency and iron deficiency) on some anthropometrical indexes (body weight and crown-rump length), brain growth and motor function in young rats. Adult male and female albino wistar rats were obtained from the breeding colony of Pasteur Institute, Iran. The female albino rats were mated with normal male rats. After delivery, 40 male rats per group were selected. In order to measure physical and brain growth a special caliper (0.01 mm) and electronic balances (0.0001 g) were used. The instruments for motor function evaluation were Morris Water Maze and Open Field Arena. The data were analyzed by one-way ANOVA and post-hoc analyses were carried out by Tukey’s test (P?0.05). There were significant effects of iron and zinc deficiency on serum iron and zinc level. The results showed that serum iron and zinc concentration after the diet (contrary to the condition before diet) in ZnD and FeD groups were significant. There was a significant difference in some anthropometrical indexes (body weight, crown-rump length) and motor function between ZnD, FeD and control groups but there was no significant difference in brain weight between ZnD, FeD and control groups. The results of this study suggest that sufficient zinc and iron affect motor function as well as physical and brain growth.
Shahzad Tahmasebi; Mehdi Shahbazi; Naser Naghdi
Volume 1, Issue 3 , January 2009, , Pages 99-116
Abstract
The purpose of this study was to evaluate the effect of dietary zinc levels during gestation on physical development of offspring. The statistical population consisted of adult male and female rats (Albino-Wistar) which were obtained from Pasteur Institute, Iran. After mating, 9 pregnant female rats ...
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The purpose of this study was to evaluate the effect of dietary zinc levels during gestation on physical development of offspring. The statistical population consisted of adult male and female rats (Albino-Wistar) which were obtained from Pasteur Institute, Iran. After mating, 9 pregnant female rats were divided into 3 groups: 1) Zinc deficient group (0.05
