---

---

Background and Objective: Patellofemoral pain is the most common and controversial musculoskeletal problem. Several studies have focused on its causes, prevention, and treatment strategies. This study was done to determine the effect of eight weeks of standard and functional stabilization training on pain and functional movement of women with patellofemoral pain.
Methods: This quasi-experimental study was performed on 45 non-athletic women with patellofemoral pain syndrome aged 18-35 years. Subjects were divided into three standard, functional stabilization training and the control group and followed for 8 weeks. Pain was measured by visual analogue scale and functional movement was measured by the KUJALA (Anterior knee Pain Scale).
Results: Severity of pain significantly reduced in the two interventional groups (standard and functional stabilization training) in comparison with control group (P<0.05). Functional movement significantly increased in the two interventional groups in comparison with control group (P<0.05). Severity of pain and functional movement had no significant difference between the two intervention groups.
Conclusion: Performing each of the exercises, standard or functional stabilization training, for eight weeks, had beneficial effect on reducing pain and improving functional movement in patients with patellofemoral pain syndrome.

---

Background and Objective: Children with ADHD suffer from motor impairment in addition to behavioral problems (hyperactivity/impulsivity, attention deficit).The cerebellum receives data from visual, vestibular and somato- sensory systems.This study was done to determine the correlation between kinetic parameters of balance performance and behavioral symptoms in children with attention-deficit/hyperactivity disorder.
Methods: This case - control study was performed on 15 children with ADHD (9.21±0.69 year) and 15 healthy children (9.27±0.75 year). Kinetic parameter of balance evaluated using sensory organization test (SOT) in different sensory conditions including visual, somatosensory and vestibular by Neurocom. Conner’s questionnaire used to assess hyperactivity and attention deficit in addition to a psychologist.
Results: Dynamic balance score in ADHD children was significantly lower in compare to controls (p<0.05). Children with ADHD had kinetic parameters of balance performance abnormality in compare to controls. There was a significant correlation between sensory contribution and hyperactivity in children with ADHD (P<0.05).
Conclusion: Children with ADHD suffer from balance dysfunction which is a result of sensory integration and attention deficit. The sensory systems analysis showed that vestibular system, partially somatosensory dysfunction is the most important factor in balance disorder in children with ADHD.

---

Background and Objective: Balance in intellectual disability individuals is very important due to the weakness in performing balance tasks. This study was performed to determine the effect of six weeks of vestibular stimulation exercises on the balance of children with mild intellectual disability.
Methods: In this clinical trial study, 30 intellectual disability boys were randomly divided into control and experimental groups. Subjects in experimental group were receiving vestibular stimulation training for six weeks. No intervention was performed on the subjects in the control group. A single leg test was used to screen the subjects with a balance of weakness. To assessment the static, dynamic and functional Balance, the Bruninks Oseretsky test was used and a Timed Up and Go (TUG) was used, respectively.
Results: After the end of the training period, static balance, dynamic balance and functional balance was significantly increased in experimental group compared to controls (P<0.05).
Conclusion: Six weeks of vestibular stimulation exercises have a positive effect on static, dynamic and functional balance in intellectual disability boys.

---

Background and Objective: Strength and flexibility are the factors affecting the athlete's performance. This study was done to determine the effect of eccentric training on knee strength and hamstring flexibility in active females with hamstring tightness.
Methods: In this clinical trial study, 24 active female athletes with hamstring tight were randomly divided into intervention and control groups. For measurement of strength, including the eccentric and concentric peak torque and the time to reach the peak torque in speeds of 60 and 180 degrees per second, isokinetic dynamometer device .For measurement of hamstring flexibility, a passive knee extension test was used six weeks before and after the eccentric training of hamstring.
Results: After six weeks of eccentric training, a significant  improvement was observed in test scores of passive knee extension (PKE) test and also in the maximum torque and time to reach the maximum torque eccentric flexor knee in angular velocity of 60 degrees per second in the interventional  group compared to controls (P<0.05).
Conclusion: Eccentric training increases flexibility and eccentric strength of hamstring muscles in active females with hamstring tightness.

---

Background and Objective: Developmental disorder and environmental factors are considered as the main causes in postural abnormalities in children and adolescents. This study was done to evaluate the role of BMI, physical activity and the use of electronic device in the status of trunk abnormalities in male adolescents.
Methods: This descriptive-analytical study was conducted on 480 boys of 13 to 15 years old in Golestan province, northern Iran. Trunk abnormalities were measured using a spinal mouse. Physical activity was assessed using a standard physical activity questionnaire. Use of electronic device was measured using the form of rate of use of electronic device.
Results: Kyphosis abnormality in 13, 14 and 15 years-old male adolescents were reported 70%, 65% and 75%, respectively. In addition, 60% of 13 years-old, 40% of 14-years-old, and 50% of 15-years-old adolescents had lordosis abnormality. There was a direct and significant correlation between kyphosis abnormalities with BMI and using electronic device as well as a reverse significant correlation between lordosis abnormality and BMI was demonstrated.
Conclusion: This study indicated that trunk abnormalities are relatively common in male adolescents in Golestan province, northern Iran. Also, BMI and the use of electronic device can also affect these abnormalities.

---

Background and Objective: Genu varus is a deformity in frontal plane that in weight bearing position whiles the medial malleolus’s touch each other, the medial knee epicondyles far from each other. Genu varus is very prevalent in soccer players. This study was done to evaluate the effect of using knee brace and lateral wedge on muscular activity amplitude in male soccer players with genu varus during running.
Methods: This quasi-experimental study was done on 15 right-footed male soccer players with genu varus and 15 healthy soccer players. A wireless electromyography system with eight pairs of bipolar Ag/AgCl surface electrodes (20 mm center-to-center distance; input impedance of 100 MΩ; and common-mode rejection ratio of >110 dB) was used to record the activity of the tibialis anterior, gastrocnemius medialis, biceps femoris, semitendinosus, vastus lateralis, vastus medialis, and rectus femoris, and gluteus medius muscles of the right leg. Electromyography data were recorded by sampling rate of 1000 Hz in selected muscles during running at five conditions including: control, 10 degrees lateral wedge, 15 degrees lateral wedge, simultaneous using 30 degrees brace and 10 degrees lateral wedge, and simultaneous using 30 degree brace and 15 degrees lateral wedge.
Results: Treatment intervention had reduction effect on muscular amplitude of biceps femoris and vastus lateralis during push-off phase (P<0.05). Muscular amplitude of biceps femoris and vastus lateralis during loading phase was reduced due to Treatment intervention (P<0.05).
Conclusion: Simultaneous using of lateral wedge and knee brace reduce the electromyography activity of vastus lateralis and biceps femoris muscles. This reduction may be associated with passive support of knee brace that in result could decrease the external knee adductor mowment.

---

Background and Objective: Foot pronation could increase injury occurrence during running. This study was done to investigate the effect of shoes with spikes containing two different stiffness on frequency spectrum of muscles during running in patients with pronated feet.
Methods: This quasi-experimental study was done on15 pronated feet runners with mean age of 27.2±6.4 years. Running was done in two conditions including double density and usual spikes Track and field shoes with between rests of 5 minutes. A wireless 8 channels electromyography system (UK) with bipolar electrodes was used to record the electrical activity of the lower limb muscles. Electrodes were located on tibialis anterior, medial gastrocnemius, vastus medialis, retus femoris, vastus lateralis, biceps femoris, semitendinosus, and gluteus medius muscles in accordance with SENIAM European protocol.
Results: Frequency content of tibialis anterior and gluteus medius at loading phase were significantly greater during running with spikes double density Track and field shoes compared with usual spike shoes (P<0.05). The frequency content of muscles did not demonstrate any significant differences during running with spikes double density Track and field shoes compared with usual spike shoes at both mid-stance and push-off phases.
Conclusion: The double density spikes track and field shoes increased frequency content of tibialis anterior and gluteus medius muscles during loading phase that could be associated with shock absorption.

---

Background and Objective: Alteration of scapular position and motion are called scapular dyskinesis (SD), that leads to symptoms such as pain in the shoulder joint. This study was performed to determine the effect of eight weeks scapular stabilization exercises on shoulder pain of archer men with scapular dyskinesis.
Methods: In this clinical trial study 30 archer men of recurve sport field with SD and shoulder pain were randomly divided into two intervention and control groups. Shoulder pain of all subjects was evaluated by using numeric pain rating scale. Then the interventional groups were received scapular stabilization exercises in three sessions per week for eight weeks. The control group performed only their normal daily exercises. At the end of the training, post-test was performed for both groups.
Results: The results of the present study showed that after scapular stabilization exercises, the reduction of dominant shoulder pain both during exercise and at rest was significant in interventional group in compared to controls (P<0.05). But in Non-dominant shoulder, there was significant effect in pain reduction only in intergroup (P<0.05) and there was no significant effect between interventional and control groups.
Conclusion: Scapular stabilization exercises can use to reduce the pain of dominant shoulder joint of archer sport men with scapular dyskinesis.

---

Background and Objective: The use of lumbar braces affects kinetics and kinematics. This study evaluated the effects of two types of simple and sensor thoracolumbosacral braces on electromyography activity of selected muscles in patients with kyphosis during running.
Methods: This quasi-experimental study was performed on 15 males with kyphosis. The subjects performed a running task in three conditions: without braces, with simple braces, and with sensor braces. An 8-channel wireless electromyography system was used to record the activity of the muscles of the lower back and lower limbs during running.
Results: There was no significant difference between the tested conditions in response to loading, middle support and swing; however, during push-off, the median frequency of the gastrocnemius muscle was greater when running with a simple brace compared with running without brace (P<0.05). In addition, the median frequency of the semitendinosus muscle was significantly higher while running with sensor brace compared with simple brace (P<0.05).
Conclusion: Using brace, especially sensor brace, can improve muscle activities in patients with kyphosis.

---

Background and Objective: Genu varum is a lower limb deformity. This study was done to evaluate the effects of shoe aging on the general and directional contraction of ankle muscles during running in females with genu varum.
Methods: This case-control study was done on 30 female students (15 individuals with genu varum degree 2 and 15 healthy individuals) using new and old sneakers for 6 months in the sports biomechanics laboratory of the University of Mohaghegh Ardabili, Iran. Each subject was given a new pair of sneakers, and after the initial data collection, the subjects were asked to use them in their daily activities for at least an hour a day for 6 months. Electrical muscle activity was recorded using surface electromyography.
Results: There was no significant difference in the general and directional contractions if ankle muscles during the running phases.
Conclusion: Shoe aging has no effect on ankle joint co-contractions.
 

---

Background and Objective: Long-standing groin pain (LSGP) is a common injury in ball games. This study aimed to compare the electrical activity of selected lumbopelvic-hip muscles during a single leg jump-cut maneuver in football players with LSGP and healthy players.
Methods: In this case-control study, 32 football players were divided into two groups: LSGP (n=16) and healthy (n=16). A force plate was used to determine the heel-contact and heel-off moment. The ground reaction forces and the average of three trials of the electrical activity of selected lumbopelvic-hip muscles during a single leg jump-cut maneuver were recorded bilaterally.
Results: At the heel-contact moment, the rectus abdominis and adductor longus muscles on the dominant side and the multifidus muscle on the opposite side showed significantly higher activity in the LSGP group compared to the healthy group (P<0.05). Similarly, at the peak of the vertical reaction force, the rectus abdominis and adductor longus muscles on the dominant side and the multifidus and gluteus medius muscles on the opposite side were significantly more active in the LSGP group (P<0.05). At the toe-off moment, the internal oblique, adductor longus, and gluteus medius muscles on the dominant side and the internal oblique, multifidus, and gluteus medius muscles on the opposite side were also more active in the LSGP group compared to the control group (P<0.05).
Conclusion: Long-standing groin pain causes changes in the electrical activity of muscle groups during different phases of the single-leg jump-cut maneuver, leading to increased dynamic stability and possibly an increased risk of overuse injuries, chronic injuries, economic consequences, and exclusion from sports activities.
 

---

Background and Objective: Fatigue is considered one of the factors effective in changing the electrical activity of muscles so that it is directly linked to increasing the potential of muscular injuries and functional decline in various stages of sports. The present study was conducted to evaluate the frequency of electrical activity of lower limb muscles before and after fatigue during running in individuals with a history of coronavirus disease 2019 (COVID-19) compared to healthy individuals.
Methods: This quasi-experimental research was conducted on 14 women with a history of COVID-19 over the past two months (the experimental group) and 14 women without a history of COVID-19 (the control group) with an age range of 18-30 years using the convenience sampling method in the city of Ardabil. The fatigue protocol started using a sophisticated treadmill at a speed of 6 km/h, and the treadmill speed was accelerated by 1 km/h every 2 minutes. The Borg’s Rating of Perceived Exertion (RPE) 6-20 Scale was used to determine the participants’ final moment of fatigue. A steady-state running fatigue protocol ended at a score higher than 17 on the Borg’s RPE 6-20 scale or 80% of maximum heart rate. Electromyography data were analyzed using the data LITE biometrics software before and after the fatigue protocol.
Results: There was a statistically significant increase in the frequency of the electrical activity of the vastus lateralis (VL) muscle between the post-test of the control group and the experimental group (d=0.410, P=0.035). The pretest-posttest difference of the frequency of electrical activity of the VL muscle after fatigue compared to before fatigue during the loading response phase during running had a statistically significant increase in the experimental group than in the control group (d=0.602, P=0.016). The frequency of the activity of the semitendinosus muscle increased after fatigue compared to before fatigue during the mid-stance phase of running (d=0.261, P=0.005). The impact of fatigue on the frequency of the activity of the VL muscle during the push-off phase of running was statistically significant (d=0.140, P=0.049). The frequency of the activity of the VL muscle increased after fatigue compared to before fatigue during the push-off phase of running in the experimental group.
Conclusion: The increased electrical activity of the lower limb muscles in various phases of running after fatigue in individuals with a history of COVID-19 can be attributed to decreased neuromuscular coordination.

---

Background and Objective: Neck pain is a prevalent problem negatively affecting individuals’ health and quality of life. Therefore, the present research was conducted to determine the impacts of neck stabilization and thoracic mobility exercises on disability, range of motion, and endurance of females with non-specific chronic neck pain.
Methods: This single-blinded clinical trial was conducted on 36 females with non-specific chronic neck pain in three 12-people groups in the city of Qom. The subjects of the first intervention group (those doing neck stabilization exercises) and the second intervention group (those doing neck stabilization exercises with thoracic mobility) performed the exercises as three 60-minute sessions per week for 8 weeks in the gym, and the control group received a set of corrective exercises. Disability, the neck range of motion, and muscular endurance were measured by the Neck Disability Index (NDI), goniometer and the Progressive Iso-inertial Lifting Evaluation (PILE) test, and biofeedback sphygmomanometer, respectively.
Results: Disability, range of motion, and muscular endurance of the subjects in both intervention groups significantly improved compared to the control group (P<0.05). Compared to the first intervention group, the range of motion and muscular endurance of subjects in the second intervention group showed a significant improvement (P<0.05).
Conclusion: Doing neck stabilization and thoracic mobilization exercises was found to be an influential intervention in the improvement of disability, range of motion, and muscular endurance of females with non-specific chronic neck pain.

---

Background and Objective: Gait is a fundamental movement pattern influenced by various structures. This study aimed to determine the effect of sand-based training on ground reaction force frequency spectrum in individuals with anterior cruciate ligament (ACL) reconstruction and pronated feet during gait.
Methods: This clinical trial was conducted on 28 male students with pronated feet and ACL injuries aged 22-25 years at Mohaghegh Ardabili University. Participants were randomly assigned to two groups of 14: A control group and a sand-based training group. The ground reaction force variables were measured using a force plate in the pre-test and post-test.
Results: The number of necessary harmonics in the free moment component decreased by 15.95% in the post-test (16.48±4.14) compared to the pre-test (19.11±2.15) of the control group (P<0.05). The number of necessary harmonics in the mediolateral direction of the ground reaction force decreased by 23.34% in the post-test (15.59±3.92) compared to the pre-test (19.23±2.66) of the training group (P<0.05). Additionally, the number of necessary harmonics in the anteroposterior direction of the ground reaction force increased by 33.04% in the post-test (21.61±2.55) compared to the pre-test (14.47±4.11) of the training group (P<0.05).
Conclusion: Sand-based training was able to improve the gait mechanics of individuals with ACL reconstruction and pronated feet.