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Background and aim: The lateral scapular slide test (LSST) is used to determine scapular position and scapular asymmetry with the arm abducted 0, 45, and 90 degrees in the coronal plane. This test was introduced by Kibler. Assessment of scapular position is based on the derived difference measurement of bilateral scapular distances and the distance of inferior angle of scapula to spinous process of T7 vertebra. The purpose of this study was to assess the reliability of measurements (intra rater, inter rater, sensitivity and specificity) of LSST in assessment of scapular asymmetry and scapular dysfunction in patients with shoulder impairments.

Materials and Methods: Subjects:  Fifty-seven subjects participated in this cross sectional study.

Twenty seven subjects in shoulder impairment group (X=47.66, SD=11.64) and thirty subjects in normal group(X=33.53, SD=11.72). Three examiners measured the distance of inferior angle of scapula to spinous process of T7 vertebra at two sides in three different positions by a caliper verneer (accuracy: 0.01 mm). Position 1 involves of the shoulder in glenohumeral joint neutral. In position 2, the humerus is placed in a position of medial rotation with 45 degrees of shoulder abduction. In position 3, the upper extremity is placed in a position of maximal medial rotation with 90 degrees of shoulder abduction. The data were analyzed with SPSS (version: 11.5). ICCs and SEMs were calculated.

Results: The ICCs for intra-rater reliability were 0.87 to 0.97 for subjects without and with shoulder impairments and 0.63 to 0.79 for inter-rater reliability in subjects with shoulder pathology (involved side). The SEMs ranged from 0.57 to 0.86 cm for intra-rater reliability and from 0.79 to 1.20 cm for inter-rater reliability. Sensitivity of the test was high(80% to 100%) but specificity  was low (4% to 26%).

Conclusion : The lateral scapular slide test has high sensitivity and good to high level of intra rater reliability at three different test positions. The test showed low specificity and poor to fair inter rater reliability at three different test positions particularly at position 3.

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Background and aim: Muscle flexibility is an important component of physical fitness and injury prevention.

Passive Stretch can be effective in lengthening and making hamstring more flexible. Popliteal angle measurement is one of the most simple method in studying the efficiency of these methods however, in goniometry measurement, there is not any data about muscle tension and any proper judgment about flexibility.  The goal of this study is to evaluate length and stiffness of the hamstrings by Quick Release Movement before and after the passive stretch.

Materials and methods:14 men (20-30 years old) with shorted hamstring (20 degree or more ext lack in passive knee ext test by popliteal angle measurement) participated in this study. Before and after exercises, popliteal angle  and muscle stiffness  were evaluated with digital goniometer and  Quick Release Movement technique respectively. Evaluation of stiffness was performed in flexion and extension positions.

Results: A significant increase in hamstring length was observed. (P<0.05) There was decrease in stiffness in both position of flex and ext but it was significant when in extension state.(P<0.05)

Conclusion: Findings of this study demonstrate passive stretch's effectiveness in increase muscle length and lessening muscle stiffness. In addition Quick Release Movement can be a suitable method for measuring muscle stiffness.

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Background and aim: Active straight leg raise test in patients with sacroiliac joint dysfunction (SIJ ) is accompanied by feeling pain on joint or heaviness and inability to lift the leg. This test has been advocated as reliable and valid test for the quality of load transfer through the lumbo-pelvic region. With respect to the important role of muscles, in pelvic stability and with respect to patients with SIJ dysfunction can not do this test easily. There is no study has been done about assessment and comparison  of changes in muscle timing of pelvic stabilizer muscles and duration of ramping time during ASLR between healthy and patients with SIJ dysfunction 

Materials and methods:Eleven female subjects with clinical diagnosis of sacroiliac joint pain and 15 match healthy female subjects were tested in the supine resting position with the ASLR. Surface electromyography of rectus abdominus , oblique externus , oblique internus  , adductor longus , biceps femoris , gluteus maximus and  erector spine muscles  were recorded during ASLR test. Timing of muscles and ramp time during ASLR  test were acquired and measured in MATLAB software . 

Results: No statistically significance were found in ramp time between two groups. The onset timing of activation of adductor longus (A.L) was delayed on symptomatic side in subject with SIJ pain (P=0.006).

Conclusion: Delayed onset of A.L suggests an alteration in strategy for lumbopelvic stabilization that may disrupt load transfer through the pelvis.

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Background and aim: The shoulder area is the most complex region of the body and inherently unstable that motions are produced and controlled by sequenced activation of muscles in force couple patterns. It seems that investigating of shoulder muscle activation pattern is essential in the various tasks in healthy subjects due to the unstable structure of the shoulder and vital role of muscles in the stability. In order to evaluate motor control changes in the various movement, designing the therapeutic programs suitable to the shoulder pain and to evaluate effects of physiotherapy and preventing of side effects, this study was conducted. Up to now, it has not been evaluated in the D1flex & D1ext patterns yet.

Materials and methods: Thirteen female healthy volunteers participated in the experiment. Dependent variables of muscle activation such as onset and offset as well as sequencing of muscles (upper trapezius, lower trapezius, serratus anterior, pectoralis major, anterior deltoid and posterior deltoid) of dominant side were calculated during D1flex & D1ext patterns by surface EMG and Data log software in the standing position with speed movement of 25 degree/second.

Results: Special patterns of muscle activation were observed during D1flex & D1ext. Sequencing of muscle activation was different in the both movement patterns. Also, significant differences were found in the latency time of all muscles (p<0.05) except upper fibers of trapezius related to flex/ext goniometer (p=0.33) between both movement patterns.

Conclusion: This study demonstrated that there are special patterns of activation of muscles around the scapulohumeral articulation in the normal subjects. Rehabilitation and conditioning programs should be designed to restore and optimize the activation sequences and task specific functions of these muscles.

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Background and aim: Muscles that contribute in production of sound have an important role in specific language. Knowledge of normal activities of these muscles is very important in language dysfunction and pathologic conditions. Needle electromyography is complementary approach in clinical evaluations of above conditions but it is a painful method for evaluating of the patient. Surface electromyography can be used to neurophysiological behaviors and effect of treatment interventions and is accepted by scientific academies. The purpose of this study is appointment of new approach in this area.

 Materials and methods: Sixty eight healthy subjects (34 female and 34 male) in range of 20-30 years old were contributed after supplement of questioner form in this study. Subjects sat in a chair with arm rest and recording electrodes placed on muscles of Thyroarytenoid and Cricothyroid of both side (right and left) at middle and lower parts of throat, near of 1 cm from midline.  Silent activity and fricative voice (z-zh) and voiceless (s-sh) activities recorded randomly at 10 second with interval rest between them for 5 repetition. All of signals processed and then compared in time, frequency and non linear measurements.

 Results: Non linear values such as Percent of recurrence, Entropy were reduced significantly in fricative voice (P<0.05).

 Conclusion:  Surface activity recording of Thyroarytenoid and Cricothyroid muscles is possible and sensitive parameter is non linear values. Surface electromyography is new approach for assessment of above muscle in clinical evaluation of speech pathologic conditions.    

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Background and aim: Asymmetric motions of trunk, external forces and other occupational factors such as frequent bending and twisting, lifting and forceful movement contribute to low back disorders. However, the dynamic and three-Dimensional motions of trunk at varying exertion levels were not addressed in literature. Hence, the aim of this study was to investigate the movement pattern and motor output during resisted trunk three-dimensional motion. 

Materials and Methods: Thirty healthy male subjects randomly performed dynamic asymmetric trunk motion at four resistance levels (nominal resistance, 25%, 50%, and 75% maximal voluntary contraction (MVC) torque) while positioned in standing with the L5-S1 interspinous space aligned with the flexion / extension axis of isostation B200. Under each resistance condition, movement patterns (range of motion), motor output (maximum torque) of the trunk were measured.

Results: In general, with increasing resistance from nominal to 75% MVC torque, the maximum torque of trunk in different directions of motion (flexion, extension, right & left lateral flexion, right & left rotation) increased significantly (p= 0.000). With increasing resistance from nominal to 50%  MVC torque, the range of motion of the trunk decreased significant (p<0.0083), but no significant change was found in this variable between resistance conditions of 50% and 75% MVC torque (p>0.0083).

Conclusion: When the resistance level is increased , the created external forces  must be balanced by internal forces generated by trunk muscles. Because the muscles have short lever arms compared with the external forces, they must generate large amounts of forces, placing compressive and shear loads on the structures of the spine. Under these conditions, spine injuries may be enhanced.

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Background and aim: Belts and back supports are frequently used to prevent low back pain. Despite many studies, there are not sufficient evidence and conclusive consensus about the effects of these supports. The purpose of the present study was to determine the effect of lumbosacral supports on motor control pattern during combined trunk motion.

Materials and Methods: 30 healthy young men were selected for the study. Temporal parameters of motor control and activity level of three pairs of trunk muscles were measured during combined trunk motion against minimum resistance and resistance equal to 50% of maximal isometric strength, under with and without back support conditions.

Results: By application of a lumbosacral support, movement response time was significantly decreased under minimum resistance (P=0/004). Application of support decreased reaction time and motor time under two resistance conditions significantly (P<0/05). No significant changes were found in trunk muscle activity levels following wearing a back support (P>0/05).

 Conclusion: By application of a lumbosacral support, individual reaction time was decreased. Although back support did not change the trunk muscle activity level, but the erector spinae muscle efficiency was increased to initiate desired movement.

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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: Swallowing disorder is one of the most important complaints of patients with upper motor neuron lesions.The rate of disphagia increases due to elderly subjects and brain injuries in our society Majority of these patients have hidden aspiration. Electromyographic assessment of swallowing can produce indicators of recovery and treatment effectiveness. This study tries to indicate pattern and recruitment of muscle activity in swallowing by surface electromyography.
Methods and Materials: Twenty healthy subjects (20-50) and ten subjects with swallowing dysfunction contribute at this study. Activities of bilateral orbicularis oris, buccinator, sternocleidomastoid and anterior region of throat muscles recorded during three stage of liquid swallowing include water, juice and honey by surface electrodes. Value of activity (RMS), duration of activity (Dur) , median (Mdf) and band (Banf) frequency of above muscles were measured.
Results: Healthy subjects indicated increase of RMS, Dur, Mdf and Banf of muscles, following increase of sweeten and viscose of liquid (P<0.05). Patients had more increase of this findings at oral muscles markedly, whereas Dur of throat muscle showed more increase in time (P<0.05). Comparison of between two groups indicated patients have more Dur time especially at throat muscles (P<0.05) and in contras reduce of activities and frequency parameters than healthy subjects (P<0.05).
Conclusion: Patients lean to keep liquid in oral phase and during throat swallow have more limitation. Patients may catch early fatigue and dysfunction for maintenance and keep of liquid particularly in throat region and it redound to change of trajectory of liquid to the respiratory tube. Therefore, rehabilitation protocols must enforce on coordination of oropharengeal muscles and recovery by movement therapy patterns.

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Background and aim: Altered muscle activity in the scapulothoracic and glenohumeral muscles is commonly believed to be a factor contributing to shoulder impingement syndrome (SIS), then, the aim of the study was to determine and compare the activity pattern of the shoulder muscles in subjects with and without SIS.
Materials & Methods: In this case-control study, 9 female subjects with shoulder impingement syndrome and 13 matched healthy female subjects were participated voluntarily by simple random sampling. Surface electromyography of serratus anterior, pectoralis major, upper trapezium, lower trapezium, posterior deltoid, anterior deltoid muscles of dominant side were recorded during D1ext and D1flex movement. Muscle activities were processed and compared in subjects with and without SIS. Non parametric test (Mann-Whitney Test)) was used for data analysis
Results: In both movement patterns, all muscles of the patient showed a greater normalized RMS than healthy group but this increase was statistically significant in anterior deltoid (p=0/003, p=0/04), pectoralis major (p=0/01, p=0/02), serratus anterior (p=0/01) and posterior deltoid (p=0/01) during D1ext and in lower trapezium (p=0/005,p=0/006) and pectoralis major (p=0/01) during D1flex.
Conclusion: The results of this study indicate that patients with impingement symptoms show abnormal muscle activity. The findings support the theory that shoulders impingement may be related to altered muscle activity in the scapulothoracic and glenohumeral muscles.

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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: Various studies indicate that background noise affects speech recognition ability of bilingual listeners (BL) more than monolingual ones (ML). However, no study has engaged in the speech recognition performance of Turkish-Persian bilinguals in the background noise. The purpose of the present study was to compare word recognition scores (WRSs) in the continuous and interrupted noises among ML Persian and BL Turkish-Persian young adults.

Material and methods: The cross- sectional analytical study was conducted by presenting speech stimuli in quiet and in the background continuous and interrupted noises at signal to noise ratios (SNRs) of -20, -10, 0, +10 dB. Two groups of 33 ML Persian and 36 BL Turkish- Persian subjects with age ranging from eighteen to twenty-five years old participated   

 Results: The degree of reduction in WRSs was significantly higher in the continuous noise relative to the interrupted one at four studied SNRs (p<0.0001) Moreover, the difference between WRSs of ML Persian and BL Turkish-Persian groups in the presence of both continuous (p≤0.001) and interrupted (p=0.002) noises was significant.

Conclusion: It seems that Persian-words recognition ability of Turkish-Persian BLs reduces more than Persian MLs in the background noises and continuous noise affects speech perception ability more than interrupted one. 

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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: Diabetes has world wide prevalence and it is estimated that up to ten years later, more than 300 million people would suffer from it. The disease has serious secondary complications. Physical activity can decrease the complications by altering the blood profiles. Patients with diabetes are unwilling to do physical exercise. Whole Body Vibration (WBV) might be a proper substitution for exercise. The effects of WBV on patients with diabetes have not been studied enough, so the aim of this study was to evaluate the effects of WBV on the blood profiles in patients with diabetes type 2.

Materials and Methods: Twenty patients with diabetes were assigned using matched assignment either into control (n=10) or intervention (n=10) group. Intervention group received the WBV with frequency of 30 Hz and amplitude of 2.5 mm for six weeks twice a week. The control group did not receive any intervention during this period. Blood profiles were measured in both groups at the baseline and the end of the study.

Results: FBS and HbA1C decreased in intervention group in comparison with the control group but the differences were not statistically significant (P=0.44).  There were not significant statistical differences in Cholesterol, HDL, LDL and TG before and after the treatment between the two groups.

Conclusion: The application of WBV with the above parameters might reduce FBS and HbA1C in patients with diabetes type 2. Increase in the amount of Glucose Transporter protein 4 (GLUT-4) is one of the contributing factors that these changes can be ascribed to.

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Background and Aim: Scapular muscles stabilization and neuromuscular control are important factors in shoulder function during dynamic activities. The three-dimensional pattern of integrated movement between gleno-humeral and scapula-thoracic joints is known as the scapula-humeral rhythm. More involved rotator cuff and scapular muscles causes more motor units are being recruited, therefore perhaps with loading on scapular muscles, can evaluate muscles role in scapular position more accurately and comprehensively.

 

Materials and Methods: Thirty male basketball players, aged between 20 to 40 years were recruited for modified lateral scapular slide test. The linear distance between inferior angle of scapula and spinous process of T7-8 was examined in 90 degrees of scaption without load and with 1 kg loading by two examiners in one session using the caliper. One of the examiners repeated the test in next week.

 

Results: Amount of inter and intra-rater intra-class correlation coefficient (ICC) for 90 degrees of unloaded scaption was 0.73 and 0.82, respectively and for 1 kg loading position was 0.54 and 0.86, respectively. Amount of standard error of measurement (SEM) in inter and intra-rater measurements for 90 degrees of unloaded scaption was 0.83 and 0.59 cm, respectively and for 1 kg loading position was 0.97 and 0.45 cm, respectively.

  

Conclusion: 1 kg loading in scaption, did not significantly improve the reliability of the test that shows the amount of load is not appropriate to activate the muscles in the athletes.

 

Keywords: Loading in scaption, Lateral scapular slide test, Athletes, Reliability .

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Background and Aim: The curves of the spine, especially lumbar lordosis, play an important role in the maintenance of an efficient upright posture and allow efficient absorption of the loads applied to the spinal column and increase the efficiency of the spinal musculature. Excessive lumbar postures, also called “hyperlordosis” and “hypolordosis” , are thought by some researchers to be indicative of altered muscle activity and stress patterns. Therefore tolerance of particular activities of daily living (ADL) of an individual with these postures is reduced. Despite the importance of neuromuscular control at spinal column maintenance and coordination, there are little investigations about the effect of thoracic and lumbar curvatures on trunk muscles activity. Therefore, the aim of this study was to investigate electromyographic behavior of trunk muscles in lordotic posture.

  

Materials and Methods: Twelve subjects with lordotic posture ( mean age 23.67 years, mean weight 56.67 kg, and mean height 162 cm) and eleven subjects with normal posture ( mean age 22 years, mean weight 59.36 kg, and mean height 164.91 cm) participated in this study. Subjects were asked to hold a load equivalent of 7% of her body weight.

  

Results: Data analysis indicated that there is not significant statistically difference in median frequency variable between two groups (p>0.05). But there is significant statistically differences at The percentage change in RMS of erector spinae and internal oblique muscles at three time periods between two groups. The percentage change in RMS of external oblique muscle has significant statistically difference at first and third time periods between two groups.

  

Conclusion: These finding reveal that excessive lumbar lordosis alter the activity levels of trunk muscles. Therefore, it seems that the use of posture correction exercises in therapeutic protocols is necessary for improvement of these changes. Also, it is recommended to do this research in dynamic tasks for attain of comprehensive information about the effect of postural deviation on electromyographic behavior of trunk muscles.

  

Keywords: Electromyography, Hyperlordosis, Posture, Prolonged load holding

  

  ^* Corresponding Author: Dr.AzadehShadmehr, Rehabilitation Faculty, Tehran University of Medical Sciences

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Background and Aim: The calculated parameters of the center of pressure (COP) are suitable indicators for evaluating balance in patients after rehabilitation. Therefore, determining the reliability level of each parameter is a matter of great importance. This study tried to determine the reliability of some parameters of the COP sway in patients with myofascial neck pain in different postural situations.

  

Materials and Methods: The present study is a test-retest reliability design. Twenty patients with myofascial neck pain performed a single and a double leg test with open and closed eyes on a force plate and with open eyes on foam in three sessions with a 30 minute intervals for 30 seconds. Antero-posterior and medio-lateral sway range, mean velocity and mean area of sway were calculated.

  

Results: The mean velocity showed high reliability (0.98) in all situations, but the other parameters were variable in different situations.

  

Conclusions: The results showed that some COP parameters are highly reliable in assessment of patients with myofascial neck pain.

  

Keywords: Reliability, Myofascial neck pain, Center of pressure, Force plate

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Background and Aim: Different aspects of the motor control parameters of dominant and non-dominant legs are investigated but the effect of dominancy on motor control strategy is still unclear. The aim of the present study is to compare the pre- motor time, motor time and reaction time in dominant and non- dominant leg muscles of the non- professional healthy athletes in response to visual stimulus during forward jumping.

Methods and Materials: Eleven non- professional healthy athletes participated in this cross-sectional study determined by convenience non probability sampling. Surface electromyography were performed in the dominant and non-dominant leg muscles including  gastrosoleous , peroneus longus, peroneus brevis, and tibialis anterior in response to visual stimulus during forward jumping.

Results: There was no significant difference (P > 0.05) between the dominant and no-dominant legs with respect to the pre-motor time, motor time and reaction time of the gastrosoleus, peroneus longus, peroneus brevis and tibialis anterior.

Conclusion: Our findings suggest that limb dominancy is not an important parameter in the motor control studies.

Keywords: Motor control strategy, Visual stimulus, Forward jumping

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Background and Aim: The aim of this study was to compare the neck and temporomandibular joint range of motion and muscle endurance in patients with temporomandibular disorders, referring to the dental school of tehran university of medical science and healthy individuals.

Materials and Methods: A total of 30 healthy men as control and 30 patients aged 20-40 years with temporomandibular joint disorders (TMD) were selected as patients. Range of motion in flexion and extension of the head and neck and mouth opening was measured and masticatory muscle endurance as well as the neck extensor muscles was measured and averaged values for each patient group were compared with the control group.

Results: Head and neck flexion range of motion and endurance of neck extensor muscles in patients with temporomandibular joint disorders (TMD) was lower than healthy controls. (P<0.001)

Conclusion: The results of this study showed that disorders of temporomandibular joint can change extensor muscle endurance and range of motion in neck. Pay attention to neck problems can be effective in improving patients with disorders of temporomandibular joint.

 Keywords: Range of motion, Muscular endurance, Temporomandibular disorder