Hanieh Mohammadi; Shahzad Tahmasebi Boroujeni; Jamal Fazel Kalkhoran
Abstract
The aim of the present study was to investigate the effect of contextual interference on balance of mentally retarded people. For this purpose, 40 educable and mentally retarded boys in Qazvin city (mean age 24.45 ± 3.120) were randomly divided into two groups: blocked and random practice. After ...
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The aim of the present study was to investigate the effect of contextual interference on balance of mentally retarded people. For this purpose, 40 educable and mentally retarded boys in Qazvin city (mean age 24.45 ± 3.120) were randomly divided into two groups: blocked and random practice. After the pretest, given their practice arrangement, subjects in each group performed their workout for 4 weeks (3 sessions per week) as the acquisition phase. Acquisition test was conducted in the last session, and then retention and transfer tests were performed after 48 hours. After Kolmogorov-Smirnov test verified normal data distribution and Leven test examined the homogeneity of variances, analysis of variance with repeated measures showed that the intervention was effective and the groups significantly improved (P=0.0005). The results of the independent t test (to compare two groups in static balance) showed that random practice group performed better in retention test (P=0.007) whereas no significant differences were observed between the groups in transfer test (P=0.061). In addition, dynamic balance results showed that random practice group performed better than the blocked practice group and it had a significant difference in retention and transfer tests (respectively P=0.001, P=0.002). So, mentally retarded people can use the beneficial effects of random practice.
Shiler Ghasem Karimi; Hasan Mohammadzadeh Jahatlo; Fateme Hosseni
Abstract
Contextual Interference is defined as interference in performance and learning that arise from practicing one task in the context of other tasks. Transitional practice is a kind of practice sequence that starts out with trials of large blocks; then moves to smaller random blocks, and eventually finishes ...
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Contextual Interference is defined as interference in performance and learning that arise from practicing one task in the context of other tasks. Transitional practice is a kind of practice sequence that starts out with trials of large blocks; then moves to smaller random blocks, and eventually finishes with complete randomization. The aim of this study was to investigate the effect of ‘transitional practice schedule’ on contextual interference in learning three badminton skills. The research was quasi-experimental with three experimental groups. The subjects were 30 female students of physical education (age: 19±1.3) from Urmia University who voluntarily participated in the study. They practiced three badminton skills (long service, forehand toss and backhand toss strokes) for ten sessions. In each session, each subject practiced 15 trials for each skill and totally 45 trials. The blocked group practiced in a blocked format. The random group practiced all three skills randomly in a way that no two similar skills would be repeated one after the other in each sequence. The transitional practice group practiced the first three sessions in a blocked format, the next three sessions with five random trials, the next three sessions with three random trials and the last session in an entirely random format. The groups' performances were recorded in each session. After the ten sessions, the immediate retention test and after 48 hours with no practice, the delayed retention test was conducted. The data were analyzed by one-way analysis of variance with repeated measures (ANOVA). The results showed that in the acquisition stage, group differences were not significant (p=0.48), but the mutual reaction (practice sessions x groups) was significant (p=0.001). In immediate retention test, only the difference between the block and random groups was significant (p=0.005) and the blocked group performed better than the random group. In delayed retention test, both random and transitional groups performed significantly better than the block group (p=0.001). Transitional group performed better than the random group and this difference was significant (p=0.043).
