نشریه رشد و یادگیری حرکتی - ورزشی
پیاپی 14 (زمستان 1392)

The aim of this study was to compare the effects of random and blocked practices with respect to the changes in generalized motor program (GMP) and parameter on acquisition، retention and transfer of table tennis service. For this purpose، 32 subjects were randomly assigned to four groups (8 subjects each group). In the first two groups، GMP changed with blocked and random arrangements while in the last two groups، parameter changed with those arrangements. After pretest، participants completed 300 trials in each task (totally 900 trials) and then they participated in posttest، retention and two transfer tests with different aims. The data were analyzed by two-way ANOVA and ANOVA with repeated measures (P˂0. 05) and Bonferroni post hoc test was used to mark the differences of the groups. The findings showed that despite the type of changes، the random practice caused better performance than blocked practice and these advantages of random practice in GMP changes were greater. However، these effects not only were observed in the same situation but also were maintained in other contexts. In addition، these effects not only influenced performance but also caused the participants to perform the tasks with more efficiency، more cognitive effort and less attention.

The aim of the present research was to investigate the effect of emotional intelligence training on mental skills in athlete teenagers. For this purpose، 80 volunteer students (40 boys and 40 girls، mean age of 15±0. 53 years) were selected with simple random sampling method and divided into two experimental and control groups. Bradberry and Greaves emotional intelligence questionnaire was used to measure emotional intelligence and Ottawa Mental States Assessment Tool (OMSAT 3) to measure mental skills. Also، the questionnaires used in Iran were reliable and valid. The program of emotional intelligence skill training to teenager athletes lasted 10 sessions. Data were analyzed using consistency of variances، Kolmogorov Smirnov test and independent t test (the mean comparisons of the two groups based on the difference of scores between pretest and posttest) at P<0. 05. Results showed a significant difference between posttest means in the two groups in four components of emotional intelligence (self-awareness، self-management، social awareness and relationship management) and mental skills (P˂0. 05). Thus، it seems that the training of emotional intelligence skills is one of the important parts of mental preparation that is necessary to achieve optimum athletic performance.

Postural control has an important role in daily activities and motor independence. In recent years، conscious aspects of postural control such as attention and cognitive processes have received attention for balance optimization performance. Therefore، the present study designed to examine the age–related differences in postural control in the internal and external focus of attention. For this purpose، displacement of the anterior–posterior، middle–lateral and speed of center of pressure (cop)، 22 elderly subjects (mean+SD=59. 95±2. 12 year) and 22 young men (mean+SD=24. 16±2. 76 year) who were selected from Shahid Chamran University students and staff purposefully and by availability were measured in three 30–second trials in the internal focus and three 30-second trials in external focus using force platform. After the normality of data had been tested with Kolmogorov-Smirnov test and the equality of variance had been tested using the Levene test، data were analyzed using multivariable variance analysis، one–way variance analysis and MANOVA. Results showed that postural stability of both groups in external focus was more than internal focus. These results supported limited action hypotheses and conscious processes. Also، in both conditions، young group had more postural stability than the elderly. It seems that the weaker performance of the elderly in both external and internal conditions was due to the effects of aging on sensorimotor systems.

Coordination، body and limb designs are related to the environmental objects and events. The aim of this study was to investigate the necessity to implement rope jumping program in Iran schools and since one of the major problems in learning how to write is eye–hand coordination، the effect of a rope jumping training course on eye–hand coordination was investigated in the fourth grade elementary students. In this case، 60 male students from fourth grade of elementary schools in Baharestan city of Tehran (in 1390-91) were selected by stage sampling method and were divided into experimental and control groups. Experimental group performed the selected rope jumping program three sessions a week for 10 weeks. To evaluate the eye–hand coordination skill، the Vienna test was used in pretest and posttest. After the normality of data was tested by K-S test، they were analyzed using independent and dependent t tests at P˂0. 05. Results indicated significant improvements in the experimental group (P=0. 44 for the right hand and P=0. 009 for the left hand). Also، there was a significant difference in the posttest mean scores of eye–hand coordination between the experimental and control groups (P=0. 0009). The results showed that the rope jumping exercise program enhanced eye-hand coordination. So this research necessitated the implementation of the rope jumping program in Iran schools.

Aging has negative effects on motor and cognitive functions، so it is essential to identify appropriate strategies to prevent the decrease of motor and cognitive functions. The aim of this research was to investigate the effect of vitamin E supplement on motor activity and spatial learning in aged rats. 36 male Albino – Wistar aged rats were assigned to three groups of control، vitamin E and sham. E group received daily 100 mg (50 IU) of vitamin E per kg of body weight with 0. 5 ml sesame oil via gavage during 8 weeks. Sham group received daily 0. 5 ml sesame oil، but control group did not receive any treatment. After the end of the protocol، open – field and Morris water maze tests were used to respectively assess motor functions and spatial learning. Distance moved and movement speed was used to assess motor function and latency and distance moved to the find platform was used to assess spatial learning. Results showed that in motor function، there was no statistically significant difference among groups in distance moved and movement speed factors (P>0. 05). In addition، there was no statistically significant difference among groups in all factors of spatial learning and memory (P>0. 05). The results showed that vitamin E did not significantly influence motor and cognitive functions of aged rats. Vitamin E supplement appears not to be efficient in the aging period when antioxidant damages caused irreversible memory destruction.

Emotional intelligence is the ability to understand and manage self-emotions and others'' emotions and includes the intelligent use of emotions. This study aimed at investigating the emotional intelligence in male and female elite athletes in team and individual sport fields. The sample consisted of 62 female elite athletes and 74 male elite athletes selected from different individual and team sports. They filled out Schutte''s emotional intelligence scale. The obtained data were analyzed by two-way analysis of variance and independent t test at significance level of 0. 05. The results showed no significant difference in emotional intelligence between male and female elite athletes (P>0. 05). Findings also revealed no significant difference in emotional intelligence between individual and team sports (P>0. 05). The results showed that female athletes benefit from emotional intelligence in their sport performance and progress as much as male athletes and also both individual and team athletes need the same degree of improvement of emotional intelligence and use it in their sport، so it is suggested that special exercises should be planned regardless of gender or sport type to increase emotional intelligence of athletes.

It is possible that society and media attention to national athletes increase their narcissism. Based on this possibility، this study which was descriptive and field aimed at comparing narcissism between elite and non-elite athlete students and non-athlete students. The population consisted of students of physical education and sport sciences faculties of Tehran universities. 105 athlete students at national and regional levels from team sports (football، volleyball and basketball) (n=35) and individual sports (wrestling، Judo and track and field) (n=35) and non-athlete students (n=35) were selected by availability method as the sample of the study. Data were gathered by Narcissistic Personality Inventory (Raskin and Terry) and Eysenck personality questionnaire (EPQ) and analyzed by ANOVA and Newman-Keuls post hoc test. The results showed no significant difference between national athlete students and regional athlete students and non-athlete students in narcissism، nervousism and psychosism (P≤0. 05). But national athletes gained higher scores in extroversion compared with regional athlete students and non-athlete students (P≤0. 05).

Motor imagery is the ability to imagine performing a movement without any action. The time a movement is mentally rehearsed highly correlates with the actual time of motor action. In this study، the effect of voluntary changes in imagery speed on the duration of the actual performance and learning a complex unfamiliar skill، and also the difference between the effects of real-time and fast imagery were investigated. 32 male volunteers (mean age: 22. 23±2. 07 yr) participated in the pretest، imagery training period، posttest، and retention test. The motor task was a sequence of new skills involving coordinated movements of upper and lower extremities with body locomotion. During the training period and in the real time، they mentally rehearsed the sequence performed in the pretest faster and more slowly. Analysis of variance (ANOVA)، dependent and independent t tests were used to analyze the data. The findings revealed that the actual duration of real-time and fast imagery group decreased after training period (p<0. 05) and it did not change in the retention test compared with the posttest (p>0. 05). However، there was no difference between the effect of real-time and fast imagery (p>0. 05). Moreover، no significant differences were found in the subsequent performance and retention of control and slow imagery groups (p>0. 05). It is suggested that the duration of motor imagery should be close to the duration of physical performance in order to promote the performance and learning new tasks and individuals should be cautious about changes in mental image speed.