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Background and Aims:

 Impaired balance and fear of falling in older adults can disrupt their daily activities and reduce their quality of life. Therefore, it is of great importance to use up-to-date and attractive exercises such as rock climbing in order to improve their balance and reduce the fear of falling. This study aims to investigate the effect of indoor rock climbing with and without environmental affordances on balance and fear of falling in older men.

Methods:

This quasi-experimental study was conducted on 36 older men aged 60-75, who were randomly divided into three groups of 12 people, including two experimental groups who performed indoor rock climbing with and without environmental affordances (educational and motivational instructions of the trainer, feedback, guidance, etc.) for eight weeks at two 40-minute sessions per week, and one control group who did not receive any training and performed routine daily activities. Three groups completed the berg balance scale (BBS) and fall efficacy scale-international (FES-I) in two pre-test and post-test phases. Paired t-test was used to examine within-group differences and the analysis of covariance was used for between-group comparisons.

Results:

Indoor rock climbing with and without affordances caused a significant increase in the BBS score (P<0.001) and a decrease in the FES-I score (P<0.001) in the post-test phase compared to the pre-test phase. Also, the BBS score of the group with affordances was significantly higher than that of the group without affordances (P=0.012), while the FES-I score in the group with affordances was lower than in the group without affordances (P=0.033). Also, the BBS and FES-I scores in the control group were lower and higher than in the experimental groups, respectively (P<0.001).

Conclusion:

Indoor rock climbing, with and without environmental affordances, can significantly increase balance and reduce the fear of falling in older men. These two techniques can be used to improve the balance and individual independence of older men.

The purpose of this cross-cultural study was to investigate the relationship between the level of physical activity and physical literacy among Iranian children. Descriptive-correlation was implemented in the current investigation. The study population consisted of 270 students from the centers of Khuzestan, Lorestan, Kurdistan, Tehran, East Azarbaijan, and Sistan and Baluchestan provinces in 2021, with an age range of 8 to 12 years (135 males, 135 girls). Using the cluster sampling method, they participated in this investigation. Data was collected using the Canadian Physical Literacy Test-2 and the International Child and Adolescent Physical Activity Questionnaire. Additionally, SPSS version 23 software was employed to conduct Pearson’s correlation coefficient test and two-way multivariate analysis of variance for data analysis. The results showed a positive and significant relationship between physical literacy and physical activity (P=0.001). The results of the geographical regions analysis indicated that the participants residing in Khorramabad, Sanandaj, and Zahedan exhibited significantly higher levels of physical activity and physical literacy than those residing in Tehran, Ahvaz, and Tabriz (P=0.001). The results of the study on the place of residence indicated that the children residing in the village exhibited a higher level of physical activity and physical literacy. Physical literacy (p=0.001) and physical activity (p=0.001) were significantly improved by gender. Based on the research findings, it seems that the physical literacy of children is influenced by a variety of factors, including gender, geographical regions, place of residence, and socio-cultural aspects. This is why it is advised that physical education programs implement decentralized planning.

Children with developmental coordination disorder (DCD) display slowness, inaccuracy, and insufficient coordination in the performance of motor skills. Compared to children with normal development, they generally have poorer performance in tasks that require visual-motor integration. We evaluated the effect of tDCS stimulation on visual-motor integration in children with DCD. In this quasi-experimental study, featuring a pre-test-post-test design, 40 students with DCD aged 7-10 years were selected according to the inclusion criteria and randomly assigned into two groups: tDCS stimulation and artificial stimulation. In the pre-test, participants took a visual-motor integration test. The intervention phase was administered for 5 consecutive days. Each day, the subjects underwent either electrical stimulation in the motor cortex (anode at C3 and cathode at Fp2) or artificial stimulation. The post-test was administered in the last session. Short-term and long-term follow-ups were performed 1 day and 42 days after the post-test, respectively. Repeated measures ANOVA was used to analyze the data. The results showed that electrical stimulation of the motor cortex significantly improves the visual-motor integration of children with DCD. The follow-up results supported the persistence of motor-visual integration in these children. In general, the results emphasized the effectiveness of tDCS exercises on motor-visual integration in children with DCD.

 Physical and mental disabilities and diseases increase with the onset of old age. On the other hand, the observation of older people who have considerably maintained their cognitive and physical abilities by changing their lifestyle rejects the belief that old age is always associated with profound physical and mental defects. In this regard, this study aimed to investigate the effectiveness of Tai Chi exercises on balance, fear of falling, working memory, and selective attention in older women.

 The present study is an applied study in which 47 older women with a mean age of 62.91±0.580 years from Tehran City, Iran, announced their readiness to cooperate after responding to a cyberspace call. Of them, 40 eligible women were selected. After performing the pretest (static and dynamic balance tests, working memory and selective attention, and falling efficiency questionnaire), they were randomly divided into experimental and control groups. Then, the experimental group participated in the Tai Chi training program online for 8 weeks, and the control group performed their daily activities. Finally, the post-test was performed, and the results were recorded. Data analysis was performed by statistical method of analysis of covariance and combined analysis of variance using SPSS software at the level of P≤0.05.

 The results of the analysis of covariance showed that the effect of Tai Chi exercises on static balance (P=0.001), dynamic balance (P=0.001), fear of falling (P=0.001), working memory (P=0.022), and selective attention (P=0.002) was significant. Comparing the groups, the results showed that in all components studied, the participants in the experimental group performed better than the control group (P=0.001).

 According to the findings, Tai Chi exercises are a useful way to improve balance, reduce fear of falling, enhance working memory, and increase selective attention in older women.

 Children have a very high ability to learn. With correct planning, we can provide conditions for them to perform various movement patterns to increase their motor skills and thus reduce the risk of skeletal injuries and obesity. This study aims to investigate the relationship between fundamental movement skills, body composition, and flat feet in children.

 This is a descriptive-correlational study on 50 healthy children (girls and boys) aged 3-6 (mean age: 5.13±0.831 years) who were selected using a convenience sampling method from Novak Kindergarten in Tehran, Iran. To evaluate the fundamental movement skills, Ulrich (2015)’s test of gross motor development was used. The InBody 270 device was used to examine the body composition, and a digital photo scanner was used to evaluate the flat feet deformity. Data analysis was performed by using the Pearson correlation test and multiple regression analysis in SPSS software, version 24. P≤.0.05 was considered statistically significant.

 The results showed a negative and significant relationship of body weight (P=0.001), body mass index (P=0.001), body fat percentage (P=0.001), and flat feet (P=0.009) with fundamental movement skills. Also, the relationship between musculoskeletal mass and fundamental movement skills was positive and significant (P=0.001), but its relationship with flat feet was negative and significant (P=0.004). The body weight had the highest power to predict fundamental movement skills, and musculoskeletal mass had the highest power to predict flat feet (P=0.001) in preschool children.

 It seems that, by improving fundamental movement skills and musculoskeletal mass index, the development of flat feet and overweight in preschool children can be prevented.

It has been shown in various researches that the focus of attention and quiet eye duration (QED) are effective variables on the performance of targeting tasks. However, the impact of these variables on motor skills in children needs more research; Therefore, the purpose of this study was to investigate the effect of different attentional focus instruction on QED and accuracy of children's darts throwing. Participants such as twelve right handed children (age: M=8.83, SD=0.79) without dart throwing experience participated in the study; while their eyes movements were recorded by an eye tracker system, participants performed 18 dart throws (6 blocks of 3 trials) under three different attentional conditions: 1) an external focus, 2) an internal focus, and 3) control conditions. The result showed that effect of focus of attention was significant neither for accuracy nor for QED. Therefore, in order to be aware of the optimal focus of children, more research is needed in various motor tasks.

The aim of this study was survey effect of perceptual motor training on motor praxis of children with developmental coordination disorder (DCD).

For this aim, 34 children (10 – 12 years old) selected as sample size and divided into two control and experimental group (20 people were in the control group and 14 people were in the experimental group) and participated in the current tests study. For recognize of DCD problem, Developmental Coordination Disorder Questionnaire- Edition 7 (DCDQ-7) and Bruininks– Oseretsky Test of motor Proficiency was performed. For investigating of motor praxis, the Dewey gesture production test, Praxis imagery questionnaire and knowledge of object use test was performed. The participants of experimental group participates in perceptual motor training for 8 weeks.

the results of MANCOVA test show that the performance of experimental group in relation to control group was improved significantly at gesture production test after perceptual motor training (P<0/05). On the other hands, in other tests (Praxis imagery test and knowledge of object use test) was no significant difference between pre and posttest in participants of experimental group (P> 0/05).

These results of current study show that perceptual motor training have significant effect on gesture production and performance of motor praxis, but this training skills haven’t effect on motor planning and programing of praxis actions in DCD children.

Balance ability is a crucial component of the independent daily activities among older adults. Balance impairment is one of the significant risk factors for falls and its related complications. Therefore, the purpose of the current study was to compare the effectiveness of neurofeedback training and training environment affordance on static balance in the elderly ‎men. This was a quasi-experimental study with a pretest-posttest control group design. The statistical population of the present study included the elderly men with an age range of 60 to 80 years living in nursing homes in Ilam, Iran, among whom 36 participants were selected using convenience sampling along with considering the inclusion and exclusion criteria, and assigned into three groups of neurofeedback, training environment affordance and control, each of which had 12 members. Participants performed a static balance task in three attempts in the pretest phase. In the intervention phase (practice), which lasted for eight weeks and included three 30-minute sessions per week, the member of two experimental groups performed the relevant exercises. It should be noted that during this period, the control group performed their usual daily activities. The posttest phase was conducted exactly after the last training session. Data were analyzed by univariate analysis of covariance (ANCOVA), the results of which indicated that neurofeedback training has a significant effect on improving static balance (anterior-posterior displacement and central-lateral displacement of the center of pressure) in the elderly men (P<0.01). Besides, training environment affordance had a significant effect on improving static balance (anterior-posterior displacement and central-lateral displacement of the center of pressure) in the elderly men (P<0.01). The results of LSD post-hoc test revealed that compared to neurofeedback training, training environment affordance had greater effect on improving static balance in the elderly men (P<0.01). According to the results of the present study, educators and geriatricians are recommended to pay attention to enriching the environment in order to improve the balance of the elderly.

The ability to walk and perform cognitive tasks simultaneously is a key aspect of daily life. Performance declines in these dual-tasks may be associated with early signs of neurodegenerative disease and increased risk of falls. Thus, interventions to improve dual-task walking performance are of great interest. The purpose of this study was to examine the effect of aerobic exercise on dual-task walking performance in in Man Schizophrenia patients with Depressive Disorder

This non-rMSE, score of depression) assigned to groups of intervention and control.  The aerobic exercise group participated in aerobic exercise program for 12 weeks, three sessions per week for one hour (totally, 36 sessions, 2160 minutes). Data of Pre-test and post-test resulting from the test of 10-meter gait speed under dual-task conditions were analyzed by Univariate analysis of covariance. Data of Pre-test and post-test resulting from the tests of N-back and Wisconsin card sorting analyzed by multiple analysis of covariance

Results showed that the two groups had significant differences in gait speed under dual-task conditions (p≤0.05). The Results of multiple analysis of covariance indicated that there was a significant difference between the aerobic exercise group and control group in post test scores of working memory and shifting attention.

According to the results of this study, aerobic exercise enhances executive functions and improves gait speed under dual task conditions. Therefore, it is recommended to include aerobic exercise in the rehabilitation programs of schizophrenic patients.

The aim of this study was to compare motor skills and body mass index of male students (7 to 10 years old) with and without internet addiction. Participants included 150 students with internet addiction and 150 students without internet addiction. After their parents filled out the consent forms and the students' personal information was recorded, the groups firstly were identified by the Kimberly Young Internet Addiction Questionnaire. Body mass index of participants were recorded by stadiometer and scale, and then their motor skills were assessed by the Bruininks - Oseretsky test. To classify the data, measures of central tendency and dispersion in the descriptive statistics were used. To analyze the data, the Kolmogorov-Smirnov test and independent t test were used in the inferential statistics. All research analysis was investigated at the significance level (P<0.05). The results showed significant differences in gross and fine motor skills, motor proficiency as well as body mass index between students with and without internet addiction, that is to say children with internet addiction showed poorer performance in gross and fine motor skills and motor proficiency. Also, they had more body mass index. Internet addiction may be accompanied with obesity and poor performance in gross motor skills. Therefore, it is recommended that the necessary steps should be taken to prevent these problems.

The elderly are one of the most vulnerable groups facing coronavirus. The aim of the present study was to evaluate the effect of green exercises on mental health and cognitive status of the elderly during the coronavirus.

This quasi-experimental and applied study was conducted on the elderly aged 60-75 years in Tabriz. The data were collected using General Health Questionnaire (GHQ) and Mini-Mental State Examination (MMSE). The experimental group performed green exercise based on the exercise program (three 60-minute sessions per week during 8 weeks). The data were analyzed using analysis of covariance (ANCOVA).

The results showed that green exercises had a significant effect on the mental health and cognitive status of the elderly. The results of this study indicated a significant improvement in general health and cognitive status of older men after a training period, which was significant compared to the control group.

Based on the results, green exercises can be used as a suitable strategy to increase the physical activity of the elderly as well as improve the mental health and cognitive status of the elderly.

Rehabilitation interventions contribute to the recovery of impaired postural control. A promising strategy to improve the efficacy of rehabilitation is transcranial direct current stimulation. We investigated whether stimulating the primary motor cortex using transcranial direct current stimulation could affect postural control in schizophrenia patients with depression.

21 men with schizophrenia and depression (mean age: 48±11/9) were selected based on inclusion and exclusion criteria and were homogeneously assigned to the stimulation and control groups. The transcranial direct current stimulation group received 2 mA stimulation for 15 min during 12 weeks over the right and left primary motor cortices. Data of the pre-and post-test studies of standing on the dominant leg with opened and closed eyes were collected.

Significant differences in static balance with opened and closed eyes and dynamic balance were observed between the experimental and control groups.

The results provide preliminary evidence indicating that transcranial direct current stimulation of the primary cortex is a safe non-invasive tool to improve static balance in schizophrenia patients with depression.

Numerous studies have examined the effects of focus of attention and quiet eye on motor performance, however the effects of these two variables in different load of task are ambiguous. Therefore, the purpose of the present study was to investigate the effect of the internal and external focus of attention instructions on quiet eye and accuracy of dart-throwing in two intensity of the secondary task. participants were 20 novice persons in dart-throwing that selected by convenience sampling; and in four dual-task conditions of internal attention-without tone estimation, external attention-without tone estimation, internal attention-with tone estimation, and external attention-with tone estimation performed dart throwing in counterbalance form that at the same time their gaze data recorded by binoculars eye tracking system. The result of accuracy showed that participants in external rather than internal attention condition and low- intensity rather than high-intensity condition had less radial error. The result of quiet eye showed that only the main effect of the secondary task was significant that participants in high-intensity of the secondary task rather low had more quiet eye duration. These results highlight the importance of external focus of attention in low and high secondary task load conditions for dart-throwing performance and direct the future research to explore more deeply the role of the quiet eye and attentional focus effects in dart-throwing performance.

Developmental Coordination Disorder is a Heterogeneous Disorder. The Purpose of this study was to determine the effect of Wii Fit training on metacognitive characteristics of children with developmental coordination disorder.

This was a applied and quasi-experimental study. The statistical population included male children (7-12 years old) with developmental coordination disorder living in Rafsanjan in 2018. Among them 30 children were conveniently recruited and randomly divided into two groups: experimental and control group (15 per each group). Then the experimentalgroup was equipped for 16 sessions (2 months and 2 sessions per week) and each session was 55 minutes in a well-equipped environment, with vigor and supervised by a medical expert to prevent the injuries of the subjects. The metacognitive questionnaire (MCQ-C) was used to assess metacognitive skills. The Kolmogorov-Smirnov test was used for normality of the data and the covariance analysis was used to compare the groups.

The results showed that Wii Fit training had a significant effect on the improvement of meta-cognitive characteristics in children with developmental coordination disorder (P˂0.05).

In general, using Wii Fit training to help people with developmental coordination disorder is likely to improve the vital aspect of psychological functioning.

  Developmental coordination disorder is a neurodevelopmental disorder that can interfere with motor coordination and that causes psychological problems. Research refer to the positive effects of training on sensory and motor functions, but could Wii Fit exercise be effective on clumsiness and quality of life these children? 

The present study aimed to investigate the effect of Wii Fit exercises on clumsiness and the quality of life in children with DCD.

The present research was a quasi-experimental study. Using  Willson (2007) developmental coordination disorder questionnaire, 30 children aged 7-12 years with DCD were selected through cluster sampling and placed randomly into two experimental and control groups. In order to evaluate the dependent variables, Bruininks-Oseretsky (1950) test of motor proficiency and Sebir et al. (2007) health related quality of life questionnaire were used. The experimental group received an intervention program for 8 weeks (2 sessions per week, 55 minutes per session). Statistical analysis was performed using multivariate analysis of covariance.

The results showed that there was a significant difference between the two experimental and control groups in the variables of clumsiness (F= 14/92, p≤0/001) and quality of life (F= 121/28, p≤0/001).

Wii Fit exercises can affect the clumsiness and quality of life of DCD children.

Introduction The aim of this study was to investigate the effect of age related differences on performance and consolidation of motor sequence learning. Method In this study, 96 healthy nervous system and right-handed boy with age range 18-6 years, were selected by available sampling. Serial Reaction Time Task was used to evaluate and compare the performance in two- component response time and accuracy. The intervention was consisted of 10 stages (8 blocks for acquisition and 2 blocks for consolidation) in which the performances of groups were compared. The data were analyzed with Mixed ANOVA in 2(type of learning) ×4(age groups) ×8(blocks) and Bonferroni was used for paired comparisons. Results In acquisition phase for response time, there was a significant main effect of block (P = 0/031) and age (P=0/001) but not learning conditions (0/431). For response accuracy, there was a significant main effect of block (P = 0/001), age (P=0/001) and learning conditions (0/003). In addition, the group's performance across the two first blocks of practice on Day 2 compare with two last blocks on Day 1 was better in response time (P=0/001) and accuracy(P=0/001) , which represents the consolidation of motor learning. Conclusion The findings showed that among different age groups, there was age-related functional changes in the acquisition and consolidation of response time and aquuracy for motor sequence task. Moreover, the various components of the movement (speed and accuracy) can be perform and consolidate in different ways. This matter should be considered in educational and rehabilitational interventions related to children and adolescents.

Motor skills in children reach to their maximum degree by going through stages of development; but this progress does not happen automatically. Being unable to reach advanced levels of these movements, decreases childhood activities and prevents reaching the ability of specialized movements. The aim of this study was to investigate the impact of badminton skills on compensating fundamental activities for children.
Girls, seven to twelve years old with lagging in movement, were participants of this study. Pretest and posttest were performed at the beginning and end of the study, using Test of Gross Motor Development (TGMD-2) method. The experiment group was trained badminton skills for 12 weeks. The control group took the same training after the tests.
There was a significantly higher performance in locomotor skills in the experimental group, compared with the control group which did not participated in any training (P = 0.001). Results were the same with the manipulation skills, indicating the impact of training (P = 0.001)
It is necessary to pay attention to compensating motor lag in the early ages, whereas training badminton skills has positive impact on this compensation of fundamental activities in children.

The aim of the current study was to investigate the effect of Paaryaad training program on the development of motor skills of children aged between 6 and 8 who suffered from high function autism (HFA). For this purpose, 30 girls with HFA (mean age 7.1 ± 0.6 yr) were randomly selected from special schools of Sanandaj city. Then, according to the pretest scores, were assigned to control and experimental groups. Pretest and posttest scores were measured by Bruininks-Oseretsky test. Motor intervention program included 16 sessions of Paaryaad training. The K-S test was used to determine data distribution and Levin and ANCOVA tests were used to compare means. The results showed that Paaryaad training program affected significantly the development of the subscales of running speed and agility, balance, bilateral coordination and strength (P0.05). According to these results, it could be argued that this training program may improve the fundamental skills of children with HFA.

This study aimed to investigate the effects of age-related changes and explicit and implicit knowledge on mixed motor sequence learning and its consolidation.
In this study, 96 right-handed boys who were healthy considering nervous system with age range of 6-18 years were selected via convenience sampling method. Serial reaction time task (SRTT) was used to evaluate and compare the performance in two components of response time and accuracy. The intervention was consisted of 10 stages (8 blocks for acquisition and 2 blocks for consolidation) in which the performances of groups were compared. The data were analyzed using mixed ANOVA test in 2 (type of learning) × 4 (age groups) × 8 (blocks) and Bonferroni test was used for paired comparisons.
In acquisition phase for response time, significant main effects were observed for block (P = 0.031) and age (P = 0.001), not learning conditions (P = 0.431). For response accuracy, significant main effects were observed for block (P = 0.001), age (P = 0.001) and learning conditions (P = 0.003). In addition, the performances of groups across the two first blocks of practice on the second day were better compared with the first day in response time (P = 0.001) and accuracy (P = 0.001), which represented the consolidation of motor learning.
The findings showed that among different age groups, there were age-related functional changes in the acquisition and consolidation of response time and accuracy for motor sequence task. Moreover, the various components of the movement (speed and accuracy) can be performed and consolidated in different ways. This matter should be considered in educational and rehabilitation interventions related to children and adolescents.

The purpose of this current study was to investigate the influence of perceptual-motor trainings on motor skills of girls with trainable mental retardation. so 20 girls with trainable mental retardation in the town of Marivan welfare organization with the average of 8/3 ±1/11 years and IQ of 39/14±6/84 with purposive sampling method were studied. All girls were pretested. Then samples based on sampling method divided into two 10 groups and considered as the control and experimental groups purposefully .In this research, for assessing the gross and fine motor skills we used sections of Bruininks _ oseretsky test . The experimental group did the perceptual-motor training for 24 sessions of practice, in a week .After 24 sessions of practice both groups were post‒test .In order to study the research hypothesis, nonparametric Wilcoxon and U Mann Whithney test were used. The results of the statistical tests showed significant difference on gross motor skills in training groups (p

Identification, prioritization and classification the factors affecting sport participation of young people for have better society is essential and this is a problem for related people with youth people. The purpose of this study was to identify main dimension of sport participation of young people and prioritization each factors. This study is applied research and In terms of data collection is types of descriptive - survey research. We use three types of questionnaire that contains: first indexes questionnaire, appointment main dimension questionnaire and a dual comparison questionnaire. After distribute questionnaires in two groups of specialist that contains 15, 10 persons and 239 young people data was collected for analysis. Finding demonstrates 4 main factors that contains 22 variables which each have prioritized than another. The result of this research in useful guideline for officials, instructors, university teacher and young people to have a better understanding of affecting factors on sport participators of young people and the importance of each variable.

The purpose of this study was to determine the effect of focus of attention and somato-sensory manipulation on postural control in older people. For this purpose 34 older men (mean of age = 70. 7) were selected and divided into 2 groups (external and internal) randomly. The task consists of performing balance task on Biodex system in three condition of normal، on foam، and on inflatable cushions. External group were instructed to focus on a picture located 6 meters from them and internal group were instructed to focus on their ankle muscles. Biodex Postural Stability System was used for measuring the subjects` balance. Overall، Medio-Lateral، and Anterior-Posterior indexes were recorded for each subject. Results demonstrated that the internal focus of attention had no significant effect on all postural indexes in three conditions (p>. 05); but External focus of attention had significant effect in conditions of standing on foam، and on inflatable cushions (p<. 01). Also external focus of attention was more effective in challenging condition (p<. 01). In total، this study showed that external focus of attention can reduce postural sway and improve balance consequently. These results are in line with Constrained Action Hypothesis. Due to this hypothesis external focus of attention results in more automatic movements and allows fast unconscious and reflective processes to control movement and improve performance and learning consequently.

The aim of this study was to determine the interactional effects of various video shows (skilled and self-model) and feedback type on performance and learning of dart throwing skill. 90 volunteers were randomly divided into 6 groups including self-control, experimenter control and yoked feedback that received either skilled model or self-model. Three groups who watched the skilled model observed dartthrowing by a member of dart national team at first and at rest intervals whereas self-model groups watched their own performance as a recorded movie. Selfcontrol groups requested feedback from the examiner during their performance. Yoked groups received feedback in those attempts on which self-control groups requested feedback and experimenter-control groups received feedback by examiner. Subjects trained for six days and then participated in the retention (after 48 hours) and transfer (immediately after retention) tests. The method of the study was semi-experimental and data were analyzed using analysis of variance with repeated measures, two-way analysis of variance and Bonferroni and Tukey post hoc tests. Results showed that all six groups improved from pretest to acquisition, retention and transfer. Regardless of the role of eedback, there was no difference between skilled and self-model in any stages. Experimenter control feedback had more efficiency than other feedbacks in the acquisition while self-control feedback was better in retention and transfer. Furthermore, results showed that those subjects who received self-control feedback had more learning when they observed self-model. The main reason why self-model-self-control feedback group was better than other groups could be the effect of motivational processes resulted from this interaction and more coordination of this feedback with subjects’ demands.

This research aimed to examine the effect of sequential stimuli technique on acquisition, retention and transfer of ocular motor sequence. First sequential stimuli, time record, response error software was designed. 60 right-handed novices (15-18 years) were divided into five groups (blocked – explicit, blocked – implicit, random – explicit, random-implicit and control). All groups performed a pretest and then (except control group) participated in five training sessions and in each session performed three blocks of ten trials with blocked and random methods. In explicit groups, participants were aware of the aim of task but in implicit groups, they were unaware. During the acquisition phase, control group were only in lab environment and the day after the acquisition, participants took part in retention and transfer tests. The data were analyzed using student-t, repeated measures and two-way analysis of variance tests. The finding showed that the subjects significantly improved in accuracy and time of response in the acquisition phase (P>0.05); but there was no significant different among groups. However, implicit learning groups progressed as much as the explicit learning groups; this finding explained the effectiveness of implicit knowledge in motor skills learning. The retention test showed that random practice was better than blocked practice in movement accuracy but the type of practice did not affect the retention of sequential reaction time. In transfer test, all groups showed transfer to the new sequence only in accuracy but not response time. However, findings showed blocked practice led to sensorimotor integration and timing, whereas random practice led to better stimulus-response association. Overall findings of this research supported this idea that learning that occurs in the context of interference can show retention and transfer to another task.

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.