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Background and aim: Muscles are involved in complex and three dimensional activities. Timing and response to onset of external trigger need to perception and processing of data in central nervous system. The propose of this study is to determine reaction time, pre motor time and motor time with and without external load in healthy subjects. 

Material and methods: Twenty healthy subjects contributed in this study. Isoinertial dynamometer was used to assess complicated motions in sagital, frontal and transverse planes from full flexion, rotation and lateral flexion to right side to opposite direction inclusive full extension, rotation and lateral flexion to left side without and with 25 and 50% MVE. Reaction time, pre motor time, motor time, and maximum torque were also measured.

Results: Following combined motions,  reaction time and pre motor time were increased by external load (25 and 50% MVE). Lateral flexion showed more changes than extension (P<0.001). By increasing load, particularly in extension time and maximum torque were changed (P<0.001).

 Conclusion: Reaction time and pre motor time in combined motions are affected under extension and lateral flexion motions. Rotation has less effect on combined motions. Motions occur in sagital and frontal plane more than transverse plane. 

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Background and Aim: Whole Body Vibration (WBV), as a new exercise modality, can improve neuromuscular performance but, there is no study to assess the effects of WBV on the reaction time as an indicator of muscular performance especially in upper extremity muscles. Therefore, the aim of the present study is to investigate the immediate effects of WBV on timing parameters of upper extremity muscles. 

Materials and Methods: Forty healthy young women were randomly assigned in two groups of intervention (with WBV) and control (without WBV). In the intervention group, timing parameters (Reaction time (RT), Premotor time (PMT), Motor time (MT)) were measured by using EMG before and after the vibration (5 sets of 30seconds at 5 mm amplitude and 30 Hz frequency) session. The same protocol but without vibration was used for control group.

Results: Whole body vibration did not alter the RT significantly (P=0.253). Premotor time was increased significantly only in the triceps muscle (P=0.006). There was also a significant difference (P=0.003) in MT of the serattus anterior muscle between two groups.

Conclusion: It seems that WBV can induce different effects on upper extremity muscles. Whole body vibration has not any significant effects on the total RT 

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Background and Aim: Measurement of reaction time and anticipation skill are used widely in therapeutic exercises or sport programs. Improvement of anticipation skill  and reaction time in any exercise or activity that need fast and correct reaction time for deciding and doing a suitable movement, can improve the motor control and its strategies as well as central processing. There is a need for an easy-to-use program that can run reaction time tasks and anticipation skills with no special experiments. There is no system for objective measurement of above variables in our country, so designing and construction of a system for reaction time test and anticipation skill estimation was carried out.

 Materials and Methods: A system that consist of software, lap top, LCD and key board was designed. The software of the system had two subsystems for measuring reaction time and estimating anticipation skill.

Results: By use of the above equipments, 6 tests of video choice reaction time, audio choice reaction time, video complex choice reaction time, audio complex choice reaction time, high speed anticipation skill and low speed anticipation skill were performed. Structural and content validity of the system was estimated very high.

 Conclusion: Current system can use in many therapeutic and sport centers simply and provide basic data about motor control strategies. By use of it, there is a better judgment about effectiveness of various treatments and sport-men selection, too.

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Background and Aim: Perceptual abilities (reaction time and anticipatory skill) are essential for successful performance in daily activities. Training in dynamic and unpredicted sport domains such as volleyball might make changes in perceptual abilities of athletes compared to non-athletes. Therefore, the aim of this study was to compare reaction time and anticipatory skill of volleyball players versus non-athletes.

 Materials and Methods: Eleven female volleyball players and 11 female non-athletes participated in this study. Auditory choice reaction time, auditory complex choice reaction time, visual choice reaction time, visual complex choice reaction time, anticipatory skill of the high speed of the ball and anticipatory skill of the low speed of ball of both groups were analyzed by a software (Speed Anticipation Reaction Test (SART)).

Results: Statistical analysis did not show any significant differences between two groups in both auditory reaction time tests (P> 0.05). However, volleyball players showed better results in visual choice reaction time, visual complex choice reaction time, anticipatory skill of the high speed of the ball and anticipatory skill of the low speed of ball tests (P> 0.05).

Conclusion: Volleyball players acquire extensive knowledge of sport specific patterns of perceptual abilities due to experiences within the volleyball domain and due to the efficient extraction of this knowledge in similar conditions such as, computerized neurocognitive tests, they have superior perceptual skills than non-athletes.

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Background and Aim: Physical and cognitive performance changes such as impairment in balance and reaction time occur with aging. In according to some studies, these disorders may be delayed by systematic physical activities. This study aimed to investigate the effect of Pilates training on the improvement of balance and reaction time of sedentary adulthood men in Kermanshah city.

  

Materials and Methods: In this study, 40 sedentary adulthood men, aged (72.15±6.74), selected and divided into two equal groups randomly. These old men lived in Elderly centers in Kermanshah. In order to measure the participants’ balance and reaction time, static balance test stork, timed up and go test and reaction time system was used. Participants participated in a course of 8-week Pilates exercise program such as stretching movements in the muscular joints balance practicing of legs, standing on one foot and deep breathing. After assurance of normality using K-S test, independent t-test was used

  for data analysis.

  

Results : The results showed in comparison with control group, participation in Pilates protocol, could improve balance and reaction time in elderly men significantly (p<.0.05).

  

Conclusion: According to results of this study , Pilates training can improve balance and reaction time of the elderly . So to improve the cognitive and motor functions of the elderly , it can be recommended to participate in physical activities such as Pilates training .

  

Key Words: Pilates training, Elderly, Static balance, Dynamic balance, Reaction time

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Background and Aim: The purpose of this study was to investigate the effects of sensory-motor integration on Balance and Reaction time in children with Developmental Coordination Disorder( DCD). Motor developmental coordination disorder (DCD) is a statement that the American Psychiatric Association was described for children who have difficulty in implementing some of the skills and competencies necessary to deal with the needs of the motor suffering their everyday lives, proposed locomotors.

Materials and Methods: This study was a semi-experimental study. Twenty patients (mean age, 8.5years old) were randomly divided into two groups of experimental and control groups from the DCD children rehabilitation center in Kermanshah. Continuous performance test, test improved stork and test walk heel to toe were used. After the pretest, the experimental group had a protocol for 8 weeks, three sessions per week of 120 minutes exercise (Swinging, jumping on Trampoline, baby turn around, turn around and coach children). To investigate the differences between the groups and the effect of exercise, ANOVA with repeated measures design with 2 × 2 (two with double measurement) were used. Post hoc t-test and t-test was used to analyze differences within groups and between groups.

Results: The results showed that the experimental group showed a significant improvement in reaction time, dynamic and static balance. There was a significant difference at post-test in experimental group due to the extent of the practice.

Conclusion: Improvement in balance is more likely due to the increased proprioception and stability. It is also likely to reduce the reaction time of integrated activities due to the pre-movement or speed up of the processing of perceptual or cognitive.

Keywords:  Sensory-motor integration, Balance , Reaction time, DCD