Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 The Effects of Increasing Running Speed on the Displacement and Velocity of the Center of Pressure 280 290 FA Mohadeseh Jafari Rajeouni Department of sports biomechanics, Central Tehran Branch, Islamic Azad University, Tehran, Iran. Razieh Yousefian Molla Department of Physical Education and Sports Sciences, Faculty of Physical Education and Sports Sciences, Islamic Azad University of Karaj, Karaj, Iran. Ali Fatahi Department of sports biomechanics, Central Tehran Branch, Islamic Azad University, Tehran, Iran. Objective The aim of this study was to determine the effect of increasing running speed on the displacement and speed of the center of sole pressure. Methods For this purpose, 28 professional runners with at least 5 years of experience in athletics, from among Tehran province teams in the national league, were selected as volunteers as a sample. After completing the informed consent form, the subjects first walked at a speed of 1.2 meters per hour to get acquainted with the treadmill. Then, slowly, the speed reached 2.5 meters per second, and after 3 minutes of running at this speed, the data were recorded for about thirty seconds. The runners then ran on the treadmill at a speed of 3.5 m / s and then at a speed of 4.5 m / s. Data were collected using special markers and 3D cameras. Analysis of variance with repeated measures and Bonferroni post hoc test were also used to analyze the data. Results The results showed that increasing the running speed would have a significant effect on the displacement rate and foot pressure of runners. As the running speed increased, so did the displacement and the pressure of the sole of the foot. Conclusion The results confirm the effect of increasing running speed on the amount of movement and speed of foot pressure.

Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 The Relationship between Static and Semi-Dynamic Balance with Accuracy and Speed of Direct Foot Kicks in Wushu Athletes 292 302 FA Hosein Bahram Tajari Department of Physical Education and Sport Sciences, Faculty of Humanities, Islamic Azad University, Hamedan Branch, Hamedan, Iran. Rasoul Nasiri Rad Department of Physical Education and Sport Sciences, Faculty of Humanities, Islamic Azad University, Hamedan Branch, Hamedan, Iran. Elaheh Azadian Department of Physical Education and Sport Sciences, Faculty of Humanities, Islamic Azad University, Hamedan Branch, Hamedan, Iran. Objective The aim of this study was to investigate the relationship between static and semi-dynamic balance with the speed and accuracy of direct kicks in Wushu athletes. Methods This was a descriptive-correlational study. 25 Wushu athletes were selected through convenience sampling. Static balance was measured using the BESS test, which included three postures of standing with paired feet, single foot, and tandem, in two stable and unstable levels. Semi-dynamic balance was measured using the Star test. To measure the accuracy of foot strike landing and the speed of kicks, two wide and narrow colored tapes were used, and the number of correct kicks was divided by the execution time (20 seconds) for speed. SPSS software was used for data analyses at a level of significance of p< 0.05. The independent t-test was used to compare the effect of target width on the accuracy and speed of kicks, and the Pearson correlation was used to examine the relationship between the balance test scores and the accuracy and speed scores. Results In the paired feet posture on a stable surface, the number of errors was significantly less than it was in other postures (p < 0.05). The relationship between static balance and the speed of kicks was weaker than the relationship with accuracy (r < 0.05). The Star test showed a moderate and positive correlation (r < 0.05). Conclusion The lack of a significant relationship between static balance and the speed of kicks indicates differences in the underlying factors of these skills. On the other hand, there was a stronger relationship between static and semi-dynamic balance with the accuracy of kicks, which suggests that balance tests could be used as an assessment or training tool in talent identification centers or in the training of these individuals.

Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 Comparing the Effect of Stabilization Exercises with and without Dry Needling on Pain and Performance of Patients with Chronic Low Back Pain 304 315 FA Mahmood Seify Department of Corrective Exercise and Sport Biomechanics, Faculty of Sport Education, Kharazmi University, Tehran, Iran Amir Letafatkar Department of Corrective Exercise and Sport Biomechanics, Faculty of Sport Education, Kharazmi University, Tehran, Iran Objective Patients with low back pain have stability defects and trigger points that cause low back pain. The aim of this study was to compare the effect of six-weeks stabilization exercises with and without dry needles on pain and performance in patients with chronic nonspecific low back pain. Methods ISixty-six patients with chronic non-specific low back pain (age 31. 6±2. 3 years, and weight 79. 6±7. 5 kg) were selected and were randomly divided into 2 equal experimental (stabilization exercises with and without dry needles) groups and one control group. At first, patients' pain and function were measured by visual analog scale (VAS) and Qswestry disability questionnaire. Then, the experimental groups underwent an intervention under supervision of the experienced trainer. But the patients in the control group did not exercise and did not receive any interventions. In the posttest stage, pain and performance were evaluated again in the three groups. The SPSS version 20 was used to analyze the data at a significance level of P <0.05. Results IThe results of the study showed a significant improvement in pain and performance of patients in experimental groups following stabilization exercises alone and with dry needling compared to the control group. Conclusion It can be concluded that core stabilization exercises with dry needles have a significant effect on reducing pain in patients with chronic low back pain and also have a significant effect on improving performance. The effect of stabilization exercises with dry needling is superior than stabilization exercises alone; thus, it is recommended that stabilization exercises with dry needling be considered in the treatment plan of patients with chronic low back pain.

Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 Investigating the Effects of Two Functional and Extra-Functional Stretching Methods of the Leg Muscles on a Selection of Kinematic and Kinetic Indicators in Women with Ankle Instability 316 328 FA Samaneh Karajiban Maher Department of Sport Science, East Tehran Branch, Islamic Azad University, Tehran, Iran. Abdolrasoul Daneshjoo Department of Sport Science, East Tehran Branch, Islamic Azad University, Tehran, Iran. Behzad Divkan Department of Sport Science, East Tehran Branch, Islamic Azad University, Tehran, Iran. Objective The purpose of the present study was to investigate the effects of two functional and functional stretching methods of the leg muscles on a selection of kinematic and kinetic indicators in women with ankle instability. Methods 24 people were selected and randomly divided into the functional exercise (8 persons), extra-functional exercise (8 persons) and control (8 persons) on the basis of inclusion and exclusion criteria. The experimental group underwent stretching exercises for eight weeks, 3 sessions each week, and the control group was merely performing its daily activities. Then, in order to measure the pre -test and post -test variables, the dorsiflexion, Plantar flexion and ground reaction force were investigated and measured. Data was analyzed using paired-samples T test and independent-samples T -tests at a significant level of 0.05 All statistical reviews were conducted using SPSS software version 25. Results The results of the T -test showed the significant effect of eight weeks of functional and Extra functional exercises on dorsiflexion, Plantar Flexion and ground reaction force. (P≤ 0/001). Conclusion The results of this study showed that the implementation of the functional and Extra-functional exercise protocol has an impact on the amount of Ankle dorsiflexion and the Plantar flexion of the Girls with an ankle instability. It was also found that muscle flexibility following the stretch ability of the gastrocnemius muscles by affecting the amount of wrist flexion facilitates the walking of the wrist installation, so these people are recommended to use the functional and Extra-functional exercise protocol.

Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 Designing and Manufacturing Smart Sports-Medical Shoes 330 342 FA Mohammad Malekipooya Department of Exercise Physiology, Professor Hesabi Branch, Islamic Azad University, Tafresh, Iran. Objective The foot is the most important organ of interaction between the ground and the human body, and its functional structure is very influential on the correct walking pattern. Examining the kinetic factors affecting the soles of the feet during static and dynamic exercises is of particular importance due to the anatomical structure of the soles of the feet. Therefore, the researcher designed and manufactured smart sports-medical shoes. Methods The present laboratory study was designed for the design and manufacture of smart medical shoes based on the sensitive sensors, time, acceleration, displacement and temperature design. This device is programmed for quantitative description and classification of different forms of exercise in field and laboratory conditions.  For this purpose, the sensors were embedded in the shoes in order to develop sports technology and movement mechanics by quantifying the information. In addition to the low cost, it is easy to use in the real training environments. The device is made up of different hardware and software components that send and receive the information in the shoe wirelessly by the module.  The information thus obtained is entered into the computer and is reviewed and analyzed with the advanced programming language C. Results IThe output results from sensors are given to the researcher and trainer for decision making. It can also exhibit the amount of pressure. After analyzing the information, the researcher describes and analyzes the data and reviews it. Conclusion These shoes can help with the help of athlete's results as well as in some foot damage along with other equipment.

Islamic Azad University, Hamedan Branch Journal of Sport Biomechanics 2476-4906 8 4 2023 3 1 The Effectiveness of Electrotherapy and Exercise Therapy on Pain and Balance in Elderly Women with Knee Osteoarthritis 344 355 FA Fatemeh Behrooz Damirchi Department of Biomechanics and Sports Management, Faculty of Educational Sciences and Psychology, Mohagheg Ardabili University, Ardabil, Iran Hamed Kheirollahi Meidani Department of Biomechanics and Sports Management, Faculty of Educational Sciences and Psychology, Mohagheg Ardabili University, Ardabil, Iran Sara Imani Brouj Department of Biomechanics and Sports Management, Faculty of Educational Sciences and Psychology, Mohagheg Ardabili University, Ardabil, Iran Sadaf Hesari Department of Biomechanics and Sports Management, Faculty of Educational Sciences and Psychology, Mohagheg Ardabili University, Ardabil, Iran Objective One of the most prevalent knee-related complications is osteoarthritis, which primarily affects middle-aged females, and the severity of this disease worsens as people age. The purpose of this study was to determine how electrotherapy treatment modalities and therapeutic exercise affect the pain and balance of middle-aged women with knee osteoarthritis. Methods The pre-test-post-test research design was used in the current semi-experimental applied research. In the physiotherapy clinic of the city of Ardabil, the statistical population were selected from among middle-aged women who had osteoarthritis in their knees. Purposive sampling was used to select 30 middle-aged individuals, ranging in age from 45 to 65, from the statistical population, and they were then randomly divided into three groups. Additionally, for eight weeks, Romberg exercises were done three times per week. Experiment and statistical analysis of variance of repeated measurements were used to compare pre-test and post-test pain. Results The analyses indicated that the effect of time factor in the pain test was statistically significant (P=0.048; d= 0.278). A pairwise comparison revealed that the electrotherapy group's post-test result was 37.99% lower than its pre-test result. The results showed that the group factor had an impact on the COPx values (P=0.019; d=0.180). The effect of the group factor on COPy values was statistically significant (P=0.034; d=0.151). Conclusion Based on the research findings, osteoarthritis can be prevented or treated to lessen its severity by making changes to one's lifestyle, engaging in disease-related exercise, and losing excess body weight before middle age.