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Introduction: Brain-derived neurotrophic factors (BDNF) play a role on induction and maintenance of memory and learning. The BDNF gene Val66Met polymorphism impairs expression of this protein. Due to difference between the neural principles operating during motor memory consolidation and the neural principles operating during practice (acquisition) and the effect of BDNF on both of these processes, the aim of the study was to study the effect of val66met polymorphism on acquisition and motor memory consolidation in the process of learning of throwing motor skill. Materials and Methods: We randomly selected one hundred university students of Kashan , Iran (mean age: 21.6±2.2 years). After blood sampling, extraction of genomic DNA, implementation of polymerase chain reaction, analyzing of PCR by 1.5 percent Electrophoresis Gel, and in the end sequencing by ABI PRISM 7000 Sequencing Analyzer, 46 participants were identified without val66met polymorphism, and 54 participants identified affected by the polymorphism (met-carriers). 10 participants of each genetic group (20 people) after pre-test practiced backhand baseball pitch for six sessions. After 48 and 96 hours they participated in two consecutive retention tests. Results: Our data showed no difference between met-carriers and people without the polymorphism in acquisition and the first retention test. However, met-carriers were significantly weaker than people without the polymorphism in the second retention test. Conclusion: These findings suggest that the BDNF val66met polymorphism has higher impact on motor learning in the consolidation phase than acquisition phase.

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Introduction: Since the people with developmental coordination disorder are weak in executive functions, the present study was aimed to investigate the effect of two different physical activity organizing methods on the executive functions of children with developmental coordination disorder. Materials and Methods: Among the children with developmental coordination disorder that were eligible to enter the study, 45 subjects were randomly selected and after completing Conner’s Executive Functioning Scale as pretest, randomly divided into three groups; random practice group (15 subjects), blocked practice group (15 subjects), and control group (15 subjects). Then, the two interventional groups performed physical practices with different underlying interactions for 8 weeks, with three 45-minute sessions each week. At the end, all the subjects underwent a posttest by executive functioning scale. Results: After the interventions, the results showed a significant improvement in the executive functions of the two intervention groups. However, no significant improvement was observed in the executive functions of the control group. In addition, a significant difference between random and blocked practice groups was observed. However, the random practice group had a greater improvement in the sensory-motor functions. Conclusion: According to our data, random physical practices can be considered as an ideal method to improve executive functions of the children with developmental coordination disorder.