فهرست مطالب کیمیا صدری

Age may limit the effect of contextual interference, but the accurate effect of age on contextual interference is not completely identified. Therefore, the purpose of the study was the effect of contextual interference practice orders on acquisition and learning of badminton skills of 45 female students aged from 10 to 12. Participants were randomly assigned to one of the three groups of blocked, random, and systematically increasing contextual interference. They trained three skills of badminton long serves, short serves, and forehand strokes for 10 sessions after pre-test. The tests consist of Acquisition, immediate retention, and delayed retention were taken after the fifth session, one hour after the end of the tenth session, and 48 hours after the last practice session, respectively. According to the findings of the study, in acquisition test, the blocked group achieved better scores than the random and systematically increasing groups. Although the three groups performed significantly better than pre-test scores in retention test, there was no difference among groups, meaning that contextual interference did not have positive results for children in learning badminton skills. Seemingly, due to the limitations in strategy, our participants were probably confused among the abundant information from the random practices and were not able to use the advantages of contextual interference. So, the benefits of random practice based on forgetting and elaborating hypotheses in this age group, especially regarding discrete motor skill in badminton is in doubt. The authors carefully suggest that elementary school physical education teachers should use blocked practice methods for badminton practice to help children build a suitable motor skills scheme and encourage them to repeat the desired skills because of the motivational feedback of blocked practice as a result of greater success in practice sessions.

It is necessary to understand the effective factors in participation in physical activity in order to increase this activity in school students. The aim of the present study was to compare the level of physical activity between field dependent/ independent students in guidance schools of Kharame city of Fars province. At first 150 male students were randomly selected and after Frame and Rod test, 100 subjects were divided into two groups: field dependent group (mean age of 12.82±0.96 years, height 155.9±6.65 cm, weight 47.5±12.27 Kg) and field independent group (mean age of 13.32±0.89 years, height 158.1±8.61 cm, weight 51±15.74 Kg). Frame and Rod test was used to measure dependence and independence and Self-assessed Physical Activity Checklist was used to evaluate physical activity. Kolmogorov-Smirnov test was used to check the normality of the data. Independent t test was used for statistical analysis in SPSS Version 17 (α=0.05). There was a significant difference in duration of physical activity between students with field dependent/independent cognitive styles (p=0.000). There was a significant difference in duration of moderate to burst physical activity between students with field dependent/independent cognitive styles (p=0.018). There was a significant difference in MET scores between students with field dependent/independent cognitive styles (p=0.000). There was a significant difference in MET of moderate to burst physical activity between students with field dependent/independent cognitive styles (p=0.012). The results of this study showed that students with field independent cognitive styles had more physical activity and energy expenditure than field independent students. It was concluded that the field dependent students may have more motor impairments and this claim needs more studies to be approved. Moreover, since cognitive style, as one of the variables which are the result of the interaction between the environment and individual and can be changed and developed, can be interfered, it is suggested that cognitive styles of the students change and encourage them in physical activity and healthier life through educational strategies.