mohammadali sanjari

This study aimed to investigate the impact of Kinesio tape (KT) on the viscoelastic properties of the lower limb, specifically stiffness and damping, before and after a fatigue protocol. KT is a commonly used therapeutic intervention believed to prevent injury, yet the available evidence on its effectiveness remains limited.

In this pre-post study, fifty healthy participants underwent countermovement jumps before and after a fatigue protocol. The study assessed the body's viscoelastic behavior under two conditions: with and without Kinesio tape (KT) applied to the gastrocnemius muscle, in both fatiguing conditions.

The findings revealed a notable reduction in lower limb damping among male participants after fatigue in the condition without tape. Conversely, in the condition with tape, there was no significant change in damping, indicating that KT may prevent the significant decrease in lower limb damping induced by fatigue.

The study offers evidence supporting the beneficial effects of KT in maintaining shock absorption capacity post-fatigue. These benefits may stem from KT's potential to enhance muscular activity and contraction force. Given that muscles act as primary shock absorbers, KT application could bolster their ability to dampen sudden impact forces post-exhaustion, potentially lowering the risk of impact-related injuries. These findings advocate for the use of KT as a preventive measure.

Two common choices exist for anterior cruciate ligament (ACL) reconstruction, autograft and allograft. Hamstring tendon autografts and soft-tissue allografts are commonly used for ACL reconstruction. The outcomes between these two grafts are controversial. This research aims to quantify and compare lower limb joint coordination between two ACL reconstruction graft options and healthy individuals.

Sixty-one athletes were enrolled after ACL reconstruction surgery (allograft, n=22; autograft, n=18). Furthermore, twenty-one healthy athletes were considered in the control group. The inclusion criteria included unilateral anterior cruciate ligament reconstruction surgery with allograft and autograft methods, male athletes with a minimum of 9 months and a maximum of two years since their surgery, successfully passing a series of quadriceps and hamstring strength tests and distance jumping before entering sports-specific activities under the supervision of a sports physiotherapist, and returning to pre-injury sports activities. 

Autograft was not statistically different from matched healthy limbs in terms of joint coordination variability and magnitude (P>0.05). However, the magnitude of joint coordination was superior to the allograft group compared to the autograft reconstructed ACL (P<0.05). 

Although our result reported no significant difference between groups in joint coordination variability, having an insight into coordinative function after ACL reconstruction will help develop postoperative rehabilitation programs as well as minimize the re-injury risk among patients. We also suggest that scholars should conduct more robust trials with valid research designs to control the results of ACL reconstruction comparison with autograft and allograft.

Quantitative biomechanical tests, along with physical assessment, may be useful tounderstand kinematics associated with graft types in anterior cruciate ligament surgery, particularly inindividuals aiming for a safe return to sport.

Sixty male soccer players in three groups participated in this study. Three equal groups of healthy, autotransplanted and allotransplanted participants, matched for age, gender, activity level and functional status, landedwith one foot on a force plate. Their kinematic information was recorded by the motion analyzer and used to describecoordination the variability by measuring coupling angles using vector coding.

The coordination variability of the allograft group in the surgical limb was significantly greater than that ofthe healthy group at least 9 months after the reconstructive surgery of the ACL and at the stage of return to sports,(F (6, 35) = 2.79, p = 0.025; Wilk's Λ = 0.676, partial η2 = 0.32). The coordination pattern in the surgical and healthylimbs of the surgical groups also differed from that of the healthy people, which was more pronounced in the allograftgroup, (F (6, 35) = 2.61, p = 0.034; Wilk's Λ = 0.690, partial η2 = 0.31).

These results show that the allograft group has a different coordination variability at return to sportthan the healthy group, so they may need more time for excessive training and competition. Level of evidence: II

According to embodied cognition theory, cognitive processes originate from the areas of the brain involved in motor programing and execution and areas that are responsible for processing sensory inputs. According to the embodied cognition perspective, cognitive systems and perception-motor systems are deeply intertwined and exert a causal effect on each other. Therefore, cognitive activity should cause changes in observable movements. For this reason, in this study, we asked participants (20 females; M age= 21±4) to listen to sentences with action verbs while standing quietly on a balance board. We then examined the standard deviation (SD) and the mean within-trial of their center of pressure (CoP) while the participants were listening to the sentences. This test was repeated for three consecutive days.The analysis of standard deviation demonstrated that CoP fluctuations changed significantly from the baseline when participants listening to action verbs. However, none of the main effects were significant for the mean of CoP. Changes in CoP fluctuations relative to normal body fluctuations while participants were asked to stand quiet and listen only to sentences indicates how cognition and motor are intertwined which was reflected in their motor behavior.

Many studies evaluate the interaction between cognition and posture but the effect of cognitive task difficulty and articulation on postural control remains inconclusive. The purpose of the present study was to examine the interaction effect of cognitive task difficulty and articulation on postural control.

Twenty healthy young volunteers (Mean age 22 ± 2.3 years) performed four random conditions while standing on a force platform. Conditions involved combinations of two level of cognitive task difficulty (easy and difficult cognitive task) and two level of verbal response (simultaneous and final).

Two-way ANOVA (significant level P<0.05) results demonstrated marked increased in the standard deviation and area of 95% confidence ellipse of the center of pressure in the difficult cognitive task condition with simultaneous verbal response. (P<0.05). Also, in the final response condition, difficult cognitive task reduced area of 95% confidence ellipse.

According to the results of the present research, it seems that the difficult cognitive task requires a greater part of attention capacity; subsequently, attention is withdrawn from the postural task and automatic control regulates posture more efficiently through unconscious, fast, and reflexive processes. Also, postural control is simultaneously affected by the difficulty of cognitive task and articulation. Therefore, for designing appropriate interventions, it seems necessary to pay attention to the interactive effects of the difficulty and articulation of cognitive task.

 It has been demonstrated that pelvic floor muscles (PFMs) are involved in the pathophysiology of stress urinary incontinence (SUI). Sense of force, an aspect of proprioception, has never been evaluated in PFMs.

 This study aimed to assess the proprioception of PFMs by evaluating the accuracy of force sense in adult women with SUI compared to those with continence. A further aim was to study the accuracy of force sense between various lengths and tensions of PFMs.

 Twenty-three women with SUI and 18 women without it were recruited in six trials with four different test conditions: 5 mm/40% (speculum opening/maximum voluntary contraction (MVC) percentage to produce), 5 mm/70%, 10 mm/40%, and 10 mm/70%. All participants were asked to reproduce the target force based on their own perceptions. The dynamometer was used to evaluate the sense of force.

 The accuracy of force sense differed between women with SUI and those without it. In all test conditions, women with SUI had higher force reproduction accuracy. The highest amount of error was recorded at 10 mm and 40% MVC for either group.

 Women with SUI were more accurate in reproducing the target force than those with continence. Higher force sense accuracy may result from more attention to the pelvic floor area and a lack of automaticity of movements in women with SUI. Therefore, developing therapeutic management focusing on restoring automaticity seems advisable.

Background and Aims:

 Whole body vibration (WBV) is one of the relatively new interventions that is widely used in physiotherapy and sports physiotherapy. It is becoming more common due to its positive effects on the neuromuscular system. The WBV device produces oscillations and its intensity is determined based on the parameters of frequency, amplitude, and duration of vibration. According to the previous studies, some parameters of this device results in increased muscle activity, strength, and power. Muscle strength and power are the two most important factors in musculoskeletal efficiency. As a result, sports performance variables such as jump height and running speed are affected by WBV. According to previous studies, if the vibration is applied with appropriate parameters, it can be effective in improving the performance of individuals in activities such as jumping and running. Furthermore, it has been shown that frequency parameter is more important than other vibration parameters since it has a greater effect on musculoskeletal performance. As a result, this study aims to review the studies on the effects of various WBV frequencies on functional variables in sports activities.

Methods:

 A search was conducted in PubMed, Scopus, and Google Scholar databases to find studies about the effect of WBV frequencies on jumping and running.

Results:

 According to previous studies, the frequency of 30-50 Hz resulted in an immediate increase in countermovement jump and squat jump heights. The frequencies of 18-35 Hz and 40 Hz, when used for a long time, also increased the heights of countermovement and squat jumps, respectively. In a few studies, the 26 and 20-Hz frequencies improved the heights of horizontal, countermovement, and squat jumps. Moreover, 30-Hz frequency increased running speed and step length and reduced the running duration in a certain distance. The frequency of 45-Hz immediately reduced the step length and increased the step rate during running on a treadmill.

Conclusion:

 The 30-Hz frequency is the most common WBV frequency with a positive effect on jumping and running abilities. In both acute and chronic conditions, this frequency may have a positive impact on the kinetic and kinematic variables of jumping and running. As a result, this frequency is suggested for improving an individual's neuromuscular performance in sports activities.

Knee extension torque control decreases after anterior cruciate ligament (ACL) rupture. There is a controversy in neuromuscular control changes on the uninvolved side. We intended to evaluate the steadiness and accuracy of quadriceps muscle control in the healthy and deficient sides of people with acute ACL rupture.  

In this cross-sectional study, thirteen men with ACL rupture (age: 27.8±7.0, body mass index (BMI): 24.7±2.25: 24.7, days from injury: 48.1±21.3) participated in the study. We measured quadriceps force control, which is quantitatively assessed by the standard deviation (SD) of joint torque for a predefined submaximal target. The accuracy of muscular control or performance of quadriceps is commonly quantified by the root mean square of error (RMSE) was also measured. A two-way analysis of variance was conducted to assess SD and RMSE of two levels of quadriceps contraction (30% of muscle voluntary contraction (MVC), 50% of MVC) across both healthy and deficient knees.  

There was a significant main effect for SD and RMSE of MVC percentage (p<0.001). SD of quadriceps torque in 50% of MVC (1.44 ± 0.13) was higher than 30% of MVC (0.88 ± 0.1). In contrast, there was no significant main effect for SD and RMSE of knee condition.  

After unilateral ACL rupture, the neuromuscular system becomes defected and quadriceps muscle control is then reduced in the healthy side. Therefore, the healthy side is also vulnerable to ligamentous damage. Besides, with the increasing intensity of physical activities, neuromuscular control decreases and the risk of re-injury rises.

Posture-cognition studies show that postural control is affected by cognitive task. Therefore, the effect of factors such as task difficulty is evaluated in dual-task paradigm but the impact of difficulty of cognitive and postural task on postural control remains inconclusive. The purpose of the present study was to examine the interaction effect of cognitive and postural tasks difficulty on postural control. Twenty healthy young volunteers (Mean age 22 ± 2.3 years) performed six random conditions while standing on a force platform. Conditions involved combinations of two level of postural task difficulty (standing on the floor and narrow base) and three level of cognitive task difficulty (without, easy and difficult cognitive tasks). Two way ANOVA (significant level p < 0.05) results demonstrated marked decrease in the standard deviation of the center of pressure in the anterior-posterior and medial-lateral directions for the difficult cognitive task condition in both postural task. (p < 0.05). Also, the easy cognitive task reduced the standard deviation of the center of pressure in the anterior-posterior direction in the narrow base standing condition (p < 0.05). According to the results of the present research, it seems that the difficult cognitive task requires a greater part of attention capacity; subsequently, attention is withdrawn from the postural task and automatic control regulates posture more efficiently through unconscious, fast, and reflexive processes. Also, postural control is simultaneously affected by the difficulty of postural and cognitive tasks. Therefore, in designing appropriate interventions, it seems necessary to pay attention to the interactive effects of posture and cognitive tasks.

According to Alvan Feinstein, the world of clinical medicine faces two challenges of mensuration and quantification. An individual-level challenge called mensuration and a group-level challenge called quantification. Feinstein calls mensuration the process of converting clinical observations (observed phenomena) into primary raw data, which are expressed as numbers and digits. Then, he called the conversion of raw data into digits and numbers specific to groups, such as the average, quantification. Quantification also has group indices to describe physical symptoms and clinical phenomena. In many scientific disciplines, the extension metry/metrics has been used to represent works based on measurement or mensuration. Combined terms with this suffix were first used by Sir F. Galton for biometry about a century ago to represent the combination of statistical committees with biological knowledge. Biometrics gradually expanded into the realm of biology, and three areas of anthropometry, sociometry, and psychometric emerged. In addition to biological activities, the scope of metrics has been widely extended to other sciences such as econometrics, technometrics, cliometric, bibliometrics, and chemometrics. Therefore, the idea and name of clinimetric is not new. The cousins of the large metrics family have been waiting for the word clinimetrics for a long time, and they may wonder why clinicians and therapists joined them so late. To express people's height, scale data in centimeters or inches, to express gender, scale data such as men and women, and to classify the severity of the disease, scales such as mild, moderate and severe or +1, +2, +3 and .... were defined. All the scales and criteria used in mensuration are to describe the types of treatments so that the observed phenomena can be divided into specific categories and analyzed. Quantification occurs after collecting primary raw data and assigning it to categories to make comparisons between them. In the categorized raw data, indicators can be calculated for each group. The average as an indicator of the health status of severely ill men receiving a treatment is one of them. In a complete and comprehensive definition, clinimetrics is an indicator of clinical phenomena. It evaluates or describes clinical and laboratory signs, symptoms, and findings using scales, indicators, and other quantitative instruments. Clinical measurement can be divided into two types of activities. One of them is mensuration in which raw data is collected to label or group so that the observed phenomena. Mensuration means what determines the status of each individual to generate such variables and raw data such as "place of birth: Mashhad", "gender: female", "age: 42" and "functional status: level 4". Another type of clinical trial can be called quantification that involves the collection of raw data in a group and summarizing the group’s characteristics, and sometimes a comparison is made between two or more groups. In quantification, it can be said that in a special group of 57 people, 81% of them were born in Mashhad, 56% were women and their average age was 46.2 years and their average functional status was level 3. Then we can compare this group with another group of people to achieve the conclusion for quantification. Over the years, the term "clinical epidemiology" has been used to quantify and compare clinical phenomena. Hence, clinimetrics is limited to mensuration activities to distinguish between these two types of measurements. On the other hand, clinical epidemiology can be a subset of clinimetrics or vice versa clinimetrics subset of clinical epidemiology. With these limitations, clinimetrics can be related to indicators, rating scales, and other conditions that are defined to describe or measure physical signs and symptoms or overt clinical phenomena in clinical medicine. Although markers, indicators, and measurements are components of clinimetrics, the main focus of this branch of science is expanding on methodology for measurement to have the necessary application. This issue is related to the quality of measuring instruments and now there is more focus on the development process of instruments than their final format. Dr. Feinstein, known as the father of clinical epidemiology, dreamed of a new field, which he introduced as clinimetrics in the early 1980s and scientists like Henrica De. Wet, Per Bech and Paul Krabbe pursued his work. He wrote a book on Clinimetrics after writing a book on Clinical Biostatistics and Clinical Epidemiology. He published four consecutive articles in the journal Ann. Intern Medicine (September to December 1983) to emphasize the necessity of basic sciences in medicine as "clinical medicine". In the last of these articles, he introduced the field of clinimetrics and predicted the types of opposition to the establishment of this field. The concept of clinimetrics gradually took its place in the medical literature. Given his scientific background in mathematics, statistics and psychometrics, he now teaches clinimetrics at the VU University of the Netherlands and has begun a wide range of activities to promote it (www.clinimetrics.nl/). He and his colleagues believe that clinimetry and psychometry are two sides of a coin. However, people like Per Bech in his book "Clinical Psychometry-2012" consider clinical psychometry to be the same as "clinimetrics" in psychiatry. Paul Krabbe of the University of Groningen in the Netherlands has dedicated chapter 13 of his book to measuring health and health status to clinimetrics. Clinimetrics has been proposed in other sciences such as physiotherapy and rehabilitation sciences by Dekker et al. (2005). Soon courses on clinimetrics will begin in faculties that deal with patients and clinical sciences (such as rehabilitation, dentistry and medicine). Perhaps the best place to start this field is in the "basic sciences" group at medical universities, so that Dr. Feinstein's dream of making the field of clinical studies as a basic field comes true. It is hoped that the pioneering universities of medical sciences in the country will also contribute to the development of this field by understanding the necessity of establishing such a field as a basic and complementary field.

Uncontrolled Manifold (UCM) approach has gained a lot of attention in the field of movement variability and related areas of research. The diversity of applications and the need to explore new UCM-based measures along with the advances in mathematical methods in UCM have led to several formulas for UCM outcome measures with different notations and conflicting interpretations. This letter is intended to summarize the most popular indexes while suggesting a unified notation.

This study investigated the effect of audiovisual integration on action-perception transfer.40 subjects were randomly divided four groups: visual, visual-auditory, control visual and control visual-auditory. Visual groups watched pattern skilled basketball player and other groups in addition to watching pattern skilled basketball player, heard Elbow angular velocity as sonification. In first stage, the pattern is presented to subjects for five times and them replying to ten questions about different aspects of pattern. Then they performed parameter recognition and pattern recongnition tests. In second stage, experimental groups watch pattern five times again and perform it after each watch. Control groups watch pattern similar to experimental group but they must not perform it. All groups responded to the questionnaire and participated in a recognition tests again. Results showed that before action, in “percent confidence reply” and no “reply to questions” there is significant different between experimental groups. But after action in both “percent confidence reply” and “reply to questions” there was significant different between experimental groups and control groups (p<0.05). In this study was confirmed effect of visual-auditory integration on action-perception transfer. This results is explainable based of Common Coding Theory, Direct Matching Hypothesis and Predictive Models. The results are consistent with modality appropriateness hypothesis.

The present study investigated the effects of physiological arousal and cognitive anxiety on performance accuracy and kinematic features of gun in expert and novice groups. The physiological arousal was recorded with skin conductance response. Performance accuracy and kinematic features of gun such as total movement time, peak velocity, displacement in horizontal and vertical axis were measured by using mixed variance analysis test with repeated measures design. Increased physiological arousal and anxiety showed induced pressure conditions. More increase in the physiological arousal in novice group led to an increase in the peak velocity and the displacement in the vertical axis of the gun and a reduction of the performance accuracy. However, the performance of the expert group increased with decreased displacement in two axes under pressure conditions. The findings support the prediction of the catastrophe model, which conceptualized based on the relationship of motor performance with physiological arousal and cognitive anxiety.

Lateral wedge insole (LWI) aims to reduce loading on medial compartment of tibiofemoral joint in mild knee osteoarthritis (KOA). This effect may be augmented by concomitant use of subtalar strap to fix the ankle joint. Moreover, longitudinal arch support embedded in insoles can cause foot comfort and may be beneficial for people with KOA. Therefore, this study aimed to assess the immediate effect of LWI with an arch support with and without a subtalar strap on the kinetics and kinematics of walking in mild KOA.

A convenient sample of 17 individuals with mild KOA (Kellgren and Lawrence grade II), aged ≥ 40 years were assessed in 3 conditions: without the insole; LWI; and LWI with a subtalar strap, where an arch support was embedded in all insoles. The primary outcomes were external knee adduction moment and angular impulse. The secondary outcomes were hip flexion and adduction moments, knee flexion angle, ankle eversion moment, and walking speed. The repeated measurements ANOVA was used to compare the primary and secondary outcomes between the conditions using SPSS.  Significance level was set at 0.05.

LWI and a subtalar strap can significantly increase the knee flexion angle at 0%-15% of the stance phase compared to no insole (p<0.001). No other changes were observed (p=0.142).

LWI with an arch, with or without a subtalar strap, cannot impose any immediate changes on the kinetics and kinematics of lower limb joints during walking in people with mild KOA.

Urinary incontinence (UI) is more common than any other chronic disease. Stress urinary incontinence (SUI), among the various forms of urinary incontinence, is the most prevalent (50%) type of this condition. Female urinary continence is maintained through an integrated function of pelvic floor muscles (PFMs), fascial structures, nerves, supporting ligaments, and the vagina. In women with SUI, the postural activity of the PFMs is delayed and the balance ability is decreased.  Many women, by learning the correct timing of a pelvic floor contraction during a cough, are able to eliminate consequent SUI. Timing is an important function of motor coordination and could be affected by proprioception. This study was conducted to review and outline the literature on proprioception as a contributory factor in SUI.

PubMed, Scopus, and Google Scholar databases were systematically searched from 1998 to 2017 for articles on the topic of pathophysiology, motor control alterations, and proprioception role in women with SUI.

A total of 6 articles addressed the importance of proprioception in motor control and its alterations in women with SUI. There were also publications on postural control, balance, and timing alterations in women with SUI in the literature. However, there was no research on measuring proprioception in the pelvic floor in this group.

Both the strength of the PFMs and the contraction timing and proprioception are important factors in maintaining continence. Thus, conducting research on PFMs proprioception in women with SUI, as a cause of incontinence, is encouraged.

Knee osteoarthritis (KOA) is associated with a decrease in function, increase in pain and risk of falls. Lateral wedge insole (LWI) is commonly prescribed in KOA to improve pain and function. Our study aimed to 1) evaluate the clinical symptoms and risk of falls in early KOA and compare with controls; 2) evaluate the immediate and four-week effect of LWI.

A sample of 20 Persian dwelling individuals with early KOA and 19 matched controls were recruited. Pain with Visual Analogue Scale (VAS), Quality of life (QOL) with the knee injury and osteoarthritis outcome score, risk of falls with the Timed Up and Go (TUG) and static One-leg Balance (OLB) tests were assessed. The four-week effect of 5º LWI was considered for individuals with KOA. Independent t-test was done to report the between-group differences, and paired t-test was used to report the four-week effect of LWI.

At baseline, statistically significant higher scores for pain, lower scores for QOL, and higher risk of falls were observed in KOA compared to controls (p People with early KOA showed higher pain and lower level of QOL that were associated with higher risk of falls. LWI may have the potential to improve clinical symptoms and reduce the risk of falls at the early stage of KOA.

After Anterior Cruciate Ligament Reconstruction (ACLR), postural control deficit remains due to sensory defect. Performing exercises based on neuromuscular training (perturbation training) may cause “postural control” and “functional level” improvement. The present study was carried out to evaluate the effect of perturbation training on postural control in patients with history of ACLR.
A total of 20 patients with history of ACLR who had followed routine rehabilitation protocol, and who returned to the previous level of activity, were included in two equal treatment and control groups. The mean time after surgery was 9.52.1 months. Force plate test was performed for evaluating the center of pressure parameters such as mean Velocity (Vm), Standard Seviation for distance (SDx), and Velocity (SDv) for each group. Also, cross hop functional test and subjective IKDC were performed for both groups. For treatment group only, 10 sessions of perturbation training were performed. Finally, these tests were repeated and compared between the two groups.
A significant increase was observed in the score of IkDC in treatment group (P- value Perturbation training can induce decrease in the center of pressure parameters, which increases functional test and IKDS scores. According to the results of the present study, performing perturbation protocol in patients who have had ACLR is recommended.

Motor skill acquisition studies have shown that the performance of a motor task will be smoother after practice; however, the type of practice is very important. Thus, the aim of this study was to investigate the effect of practice with task-specific instability on performance and acquisition of a throwing skill.
This quasi-experimental study was conducted on 16 semi-skilled subjects under 2 practice conditions, with and without availability of visual feedback. Each practice stage involved 3 blocks of 10 trials. The subjects’ throwing skill was evaluated in pretest and posttests, before and after the practicing stages. Two repeated measures ANOVA and paired t-test were used to examine the differences between subjects in practicing and test stages at a significance level of 0.05.
No significant difference were observed between practice blocks in the two stages of practice; however, there were significant differences between pretest and posttest with blocks in the second stage (P = 0.001). Moreover, no significant differences were observed between the posttests of the two practice stages.
Task-specific instability with blocking of visual feedback not only induces the acquisition of complex motor skills, but also prepares the individual for confronting unstable conditions. It is suggested that coaches and therapists train athletics and patients for performing complex skills under unstable conditions to better prepare them for confronting these conditions.

This study investigated the effect of audiovisual integration on perception and action and perception-to-action transfer. For this purpose, 30 subjects were selected and randomly divided to three groups: visual, visual-auditory (single-channel), visual-auditory (two-channel). Subjects in the visual group watched the pattern of a skilled basketball player, while the other groups were provided with the sonification of elbow angular velocity (one- channel group) and elbow and wrist angular velocity (two-channel group) in addition to watching the pattern. The pattern was presented to subjects five times and participants answered ten questions about different aspects of the pattern. Eventually, they participated in parameter recognition and pattern recongnition tests. For each elbow and wrist joints, four variables were identified: Maximum flexion angular velocity Error (MfavE), Maximum extention angular velocity Error (MeavE), Maximum range Error of flexion (MrEf) and Total Parameter time (TPt). Results showed that on “percent confidence reply” and “reply to questions” there was significant difference between experimental groups. Results showed that in movement reproduction stage in variables (MeavE) and (TPt) for both elbow and wrist joints, there was significant difference between groups in favor of the audiovisual groups. This study supports the positive effect of visual-auditory integration on perception and reproduction. Moreover, positive perception-to-action transfer was confirmed for two sensory groups. The results are consistent with modality appropriateness hypothesis. The results indicate that due to certain temporal adjustments in basketball jump shot task, the modality that dominates the perception in the context of this task is auditory.

Flat foot, as one of the common foot deformities can affect gait biomechanics and risk of lower extremity injury. Fatigue, as a high load task, can also change biomechanical parameters of locomotion. Studying normal and flat footed individuals under high load tasks such as fatigue can elucidate their differences more easily..
In this study, center of pressure (CoP) changes were studied between individuals with flat and normal feet after fatigue. CoP is one of the important gait measures which can show various biomechanical behaviors of different foot shapes..
Seventeen subjects with normal feet and 17 with flat feet walked across two force plates before and after a functional fatigue protocol. Standard deviation of CoP in mediolateral direction (SD of CoPx) and in anteroposterior direction (SD of CoPy), overall mean velocity of CoP and length of CoP construction line of both groups were analyzed. The values of SD of CoPy and length of CoP construction line were normalized to individual foot lengths prior to statistical analyses..
There were no significant between-subject effects for all CoP measures. The only significant finding was the within-subject effect for the SD of CoPy (P = 0.008) with a large effect size (partial eta squared = 0.21). Fatigue resulted in lower SD of CoPy in both groups..
Lower SD of CoPy indicates less fluctuation of CoPy and a probable less center of mass movement which could reduce the risk of injury. Furthermore, the similar fatigue response in both groups of individuals with normal and flat feet indicates a similar biomechanical behavior despite their different foot arch height..

Vertical jump is one of the basic sport activities and a popular test in the field of rehabilitation and sport which can assess the performance and power of lower extremity and musculoskeletal system. As fatigue is one of the factors that could increase the risk of injury, in this study the effect of fatigue on vertical jump was compared between healthy women and men.
18 women and 14 men performed the vertical jump before and after a functional fatigue protocol included 5 sets of consequent hops. Hopping consists stretch-shortening cycles which can mimic the natural behavior of muscle contraction in sport and daily living activities. Vertical jump height was studied variable in this research. Data were analyzed using repeated-measures analysis of variances (ANOVA) test.
No significant interaction between fatigue and group was observed for vertical jump height. Statistical analysis showed the greater value of jump height in men before and after the fatiguing condition. Furthermore, fatigue resulted in decrease in jump height value in both groups.
The main finding of this study was the similar response to fatigue in both groups. It seems that muscular fatigue prevents the proper muscular action to absorb the impact of landing. It results in more transfer of energy to the upper joints of lower extremity and increases the risk of injury.

Due to biomechanical differences, various patterns of muscle contraction are expected to occur while walking over ground versus when walking on a treadmill..
This study aimed to compare amplitude and duration of activation of selected trunk and lower extremity muscles during over-ground and treadmill walking..
Through a simple sampling method, 19 sedentary healthy men within the age range of 20 - 40 were selected. Surface electromyography of rectus abdominis, external oblique, longissimus and multifidus muscles as the selected trunk muscles and vastus medialis, vastus lateralis and hamstrings as the selected lower limb muscles were recorded..
In each gait cycle, there were no statistically significant differences in duration of selected trunk as well as lower limb muscles activity between treadmill and over-ground walking. However the mean amplitude of rectus abdominis (P = 0.005), longissimus (P = 0.018) and multifidus (P = 0.044) as the selected trunk muscles as well as the mean amplitude of vastus lateralis (P = 0.005) and vastus medialis (P Due to the stabilizing role of trunk and lower limb muscles during walking, these muscles seem to be active throughout the entire gait cycle. The increased muscle amplitude on treadmill can demonstrate that more motor units may be recruited during the contraction, which can be helpful in prescribing the appropriate type of exercise especially for patients with core muscle weakness..

The effects of exercise volume on the pattern of muscle activity is one of the most important factors in training management and injury risk reduction. In the lower limb, the quadriceps muscle which plays a determining role in performing the stance and other karate techniques could be injured in intensive exercise and may induce anterior knee pain in athletes..
The aim of this study was to determine the relationship between training volume and muscle activity of vastus medialis and vastus lateralis and its association with anterior knee pain in karate elites..
Patients and Male and female athletes from national junior and cadet karate team (14 to 18 years) were invited to participate in the study at the beginning and the end of the training camps. Studies involved measurement of electromyographic muscle activity of vastus medialis and vastus lateralis in both lower extremities with surface electromyography device and assessment of movement by electrogoniometery. Muscle activity was recorded in three tests of dachi, walking up and walking down stairs. Simultaneously, anterior knee pain was evaluated using visual analogue scale and anterior knee pain scale questionnaire..
Eight athletes of a total number of 23 reported increased ratings of pain in their right knees. No differences in muscle activity were observed in tests of Dachi and stairs between the groups with and without pain. Comparing Dachi task pattern at the beginning and end of training camps, there was no significant difference in pattern of biomechanical movement; however, reducing the amount of muscle activity in early and late phases of tasks was observed in electromyographic assessment..
The results showed that performing the same task after a six-week training period, less muscle activity was required in all phases in two groups of tasks, including karate-specific movement (dachi) and activities of daily living (up or down stairs)..

The purpose of the present study was to examine the effect of different attentional strategies on the accuracy of free throw as well as to examine the role of visual information in basketball novice throwers. Fourteen novice throwers from 21 to 28 years old were recruited. Participants performed 20 trials as counterbalance in various attentional conditions and in general performed 80 trials. In each attentional condition¡ half of the trials were performed using visual information and the other half of the trials were performed without the presence of visual information. The results of the factorial variance analysis with repeated measure indicated that the main effect of internal-external attention¡ the presence and non-presence of visual condition as well as the interactional effect of internal-external / relevant-irrelevant attention was significant. The other effects were not significant. In other words¡ the findings indicated that the external relevant attentional strategies in both visual and nonvisual conditions was better that the other strategies. Therefore¡ it can be suggested that it is better the coach’s use from external relevant attentional strategies.

ACL injury is one of the most common sport injuries which undergo reconstructive surgery. Electromyography or recording of muscles’ electrical activity is a suitable means to assess changes in motor control system output. The goal of this study is to compare the lower limb muscles EMG activity during drop landing in individuals after ACL reconstruction and healthy subjects.
Eleven men who had undergone ACL reconstruction 6 to 24 months ago (Age 29±6 years old) and 11 healthy men (Age 28±2 years old) participated in the study. Amount of electrical activity for tibialis anterior, vastus medialis, vastus lateralis, semitendinosus and biceps femoris muscles was recorded using surface electrodes during drop landing and calculated for two time intervals. The amount of activity was measured in -150 to and to intervals in relation to the landing moment. Subjective IKDC questionnaire and cross-over hop functional test were used to determine the subjective and objective functional level. Independent t test was used to determine between-group statistical differences.
Feed forward activity of semitendinosus (P=.041) and biceps femoris (P=.008) muscles were significantly higher in ACLR group and feedback activity of vastus medialis (P=.03) muscles was significantly lower in ACLR group. Healthy individuals showed higher score on both the functional test and IKDC questionnaire. (P Individuals who had undergone reconstructive surgery of ACL showed different muscular activity compared to healthy subjects and closer to ACL deficient individuals 6 months after surgery and routine rehabilitation.