Journal of Sports and Motor Development and Learning
Year:2010 | Volume:- | Issue:3|Papers Count:10

The purpose of this research was to compare block, random and randomized block training on the acquisition, retention and transfer of volleyball serves. For this purpose, 34 students of Shomal university were selected randomly and after primary rules of volleyball were explained and instructed and pretest was performed, they were divided into 3 groups (block, random and randomized block training). The subjects participated in 15 practice sessions (5 weeks, 3 sessions each week). After the training sessions, posttests including acquisition test (exactly at the end of the last session), retention and transfer tests (after one week) were performed. Kolmogorov – Smirnov (K-S) test, one-way ANOVA, and post hoc Tukey test were used to analyze the data. The results showed that in the acquisition stage, the block group significantly had better performance than the others. But in the retention test, there was no significant difference among groups. Meanwhile, the randomized-block group had significantly better performance in the transfer test.

The aim of this study was to compare the effect of self-control, frequent and reduced feedback of KR on children's learning skill of throw targeting in Aleshtar city. For this purpose, 60 subjects were selected and assigned through step-by-step random method to three groups of self-control, frequent, and reduced. They performed the task of targeting through throwing in two steps of acquisition and retention with a delayed interval of 24 hours. The self-control group was divided into two groups of high (more than 30%) and low frequency (lower than 18%) after the acquisition phase. In both phases of acquisition and retention, inferential and descriptive statistics were used. In descriptive statistics, central indexes and dispersion of variables, in inferential statistics in acquisition phase, analysis of variance (series of practical efforts) 6 × 4 (how to present feedback) and in retention phase, one-variable analysis of variance and Tukey post hoc test as well as SPSS 11.5 software were used (P≤0.05). The results indicated no significant difference among these groups in acquisition phase. In retention phase, frequent group had better performance than other groups. The comparison between coach-oriented and subject-oriented practice methods shows that frequent coach- oriented practice method leads to better results for children.

The aim of this study was to determine the effectiveness of physical practices on the reduction of slow-pace children's aggression. For this purpose, 20 guidance school students with slow pace were selected through simple random sampling. They were divided into experiment (10 persons) and control (10 persons) groups. Rosenzweig frustration scale was administered to both groups as the pretest. Experiment group exercised physical practices for one month. Then, Rosenzweig frustration scale was administered to the two groups again. Covariance analysis results showed significant differences (F=40.65, P>0.001) between the two groups. Results indicated a reduction in aggression and an increase in conformity of experimental group. Therefore, regular physical practices can reduce aggression and increase conformity in slow-pace students.

The purpose of this research was to study growth hormone (GH) response to a session of maximal exercise in active adolescents. For this purpose, 15 subjects (8 females: age 13± 0.5 yrs, height 153.25± 3.73 cm, weight 43± 5.10 kg and 7 males: age 14± 0.5 yrs, height 166.86± 6.07 cm, weight 52.86± 5.61 kg) performed an incremental exercise protocol on a treadmill with an increasing grade until volitional exhaustion. Blood samples were collected from venous blood of the subjects before and immediately after the exercise. T-test and Pearson correlation were used to analyze the data. The results showed a significant increase in serum GH concentration after exercise in both boys and girls (P<0.05). Also, no significant difference was found before exercise in both groups (1.99 vs. 1.12 ng/ml; P>0.05). But GH response was significantly higher in girls than boys (12.39 ng/ml, 4.23 ng/ml respectively). Regression analysis revealed no significant correlation between BMI and GH responses before exercise in girls and boys. Results from the present investigation indicated an increase in GH concentration after exercise and that women had greater GH release.

The aim of this study was to compare the effect of audience and music on learning and performance of basketball free throw. Subjects were 36 healthy non-athlete girls (age: 22.8±1.59 years, height: 163.1± 5.63 cm and weight: 54.5±7.06) who were randomly divided into three groups of audience (n=12), music (n=12) and control (n=12). Protocol of acquisition phase included basketball free throw for 6 weeks, 3 sessions per week, and 15 trails each session with the presence of motivational factors in separate groups. Score of free throw test was recorded per session. Then, posttest was carried out and finally after 2 weeks of detraining, retention test was performed in the same condition for all groups. Transfer test in a new condition (different from training condition) was performed 24 hours later. Heart rate index was used to asses the level of arousal of subjects at rest and during training. To analyze data, one-way ANOVA test, analysis of variance with repeated measures and Bonferroni post hoc test were used. Results showed that all groups improved in the acquisition phase and there was no significant difference in free throw scores among the three groups in the acquisition test (P=0.145). But in the retention test, music group achieved highest scores and in transfer test, music and audience groups were significantly higher than the control group (P=0.000).

The purpose of this study was to investigate general health condition, outbreak of depression and body mass index (BMI) in athlete and non-athlete students of Tehran University. Both female and male junior students participated in this study and 200 students, 50 athletes and 50 non-athletes were selected. In order to determine general health and outbreak of depression, questionnaires of general health and Beck's depression test were used, and in order to determine BMI, height and weight of the subjects were measured. In order to analyze the data, two-way ANOVA test and Pearson correlation coefficient were used. The results of this study showed no significant difference in the average value of BMI between athlete and non-athlete students based on their gender (P=0.09), but there was a significant difference in BMI between female and male students. No significant interaction was observed between gender and physical activity in BMI index. There was a significant difference in general health between athlete and non-athlete students based on their gender (P=0.007). There were no significant differences among general health subscales, BMI and Beck scores of students based on their gender and physical activity. However, there was a significant relationship between GHQ28 subscales and Beck scores based on gender and physical activity.

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<ZN<1.5 ppm); 2) Control group (Zn=40 ppm); 3) Zinc supplement group (Zn=50 ppm). A special diet was imposed on the mother during the last three months of her pregnancy. After delivery, 14 offspring were selected by random sampling in each group and some of their anthropometric indexes (height and weight) and brain growth (brain weight, head width and head length) were measured. The statistical analysis were t-test and one-way ANOVA (P<0.05). Post hoc analysis was made by Tukey test. The results showed a significant decrease in some anthropometric parameters (body weight, crown-rump length, tail length) and brain growth (head length) in zinc deficient group as compared to the control group (P<0.05), but there were no significant differences in head width and brain weight between zinc deficient and control groups (P>0.05). There was a significant decrease in crown-rump length in zinc supplement as compared to control group (P<0.05), but there was no significant difference in brain growth (P>0.05). These findings suggest that zinc deficiency during the last three months of pregnancy impairs brain and physical growth of offspring and to impose enhanced zinc supplement during the last three months of pregnancy has negative effects on physical development.

The purpose of this study was to show types and extent of offensive behaviors at soccer stadiums and to test the relationship between personal factors, spectators, verbal behavior of stadium executives and staff, sport media biases, modeling from famous team spectators, refereeing the matches, and win-oriented spectators with offensive behavior of the spectators. A total of 727 researcher-made questionnaires were randomly distributed and collected in last 10 sensitive matches of Iran soccer premier league using cluster sampling. Correlation coefficient and multi regression analysis were used to analyze the data. Results showed that verbally offensive behaviors such as motto against players and fans of competitors and trumpet on streets were more prevalent than violence. Causes of spectators' offensive behaviors were analyzed and discussed.