heydar sadeghi

This study aimed to determine the effect of a structured aquatic balance–strength training program on anteroposterior and mediolateral center of pressure (COP) velocity and displacement in postmenopausal women with osteoporosis.

In this randomized quasi-experimental study, 24 postmenopausal women with osteoporosis were randomly allocated to either an experimental or control group. The experimental group completed a 12-week aquatic balance–strength training program. Postural control was assessed using a Kistler force plate (Model 9260AA6) by calculating COP mean velocity and displacement amplitude in the anteroposterior and mediolateral directions during four standing tasks: (1) bipedal stance with eyes open, (2) bipedal stance with eyes closed, (3) semi-tandem stance with eyes open, and (4) semi-tandem stance with eyes closed. Data were analyzed using paired t-tests and analysis of covariance (ANCOVA) in SPSS (version 21), with the significance level set at 0.05.

After adjustment for baseline values using ANCOVA, the experimental group demonstrated significant improvements in COP mean velocity and displacement amplitude in both directions compared with the control group (p < 0.05). Pre- to post-test change scores further confirmed that these improvements occurred exclusively in the training group, whereas no significant changes were observed in the control group. Improvements were particularly pronounced in the anteroposterior direction and under more challenging stance conditions, such as reduced base of support or eyes-closed tasks.

Aquatic balance–strength training significantly enhances postural control in postmenopausal women with osteoporosis by improving anteroposterior and mediolateral COP measures. Longitudinal studies with extended follow-up periods are needed to determine the persistence of these adaptations.

The mechanical interaction between the human body and sports surfaces plays a critical role in maintaining functional stability and minimizing mechanical load. This study ergonomically examined sports surface stiffness within the typical indoor range (300–500 kN/m) and its influence on lower-limb mechanical behavior during a cyclic hopping task.

Thirty male athletes with similar training backgrounds performed hopping across four stiffness conditions. Vertical ground reaction force (vGRF) data were collected using a force plate and analyzed via Fast Fourier Transform (FFT). Peak force, median frequency, and the 99.5% frequency components of the vGRF were compared across surfaces using repeated-measures ANOVA with Bonferroni-adjusted post hoc tests (α = 0.05).

Median frequency on the force plate was significantly higher than on all other surfaces (p < 0.001; large effect size η² = 0.437). The 99.5% frequency was greatest on the 500 kN/m surface (η² = 0.348), although the 300 kN/m surface did not differ from the force plate (p > 0.05). Conversely, peak vGRF was lowest on the 500 kN/m surface (p < 0.001; very large effect size η² = 0.654).

The 300 kN/m surface produced more favorable force-frequency characteristics, whereas the 500 kN/m surface reduced mechanical loading. Overall, a stiffness range between 300 and 500 kN/m may provide an optimal balance between minimizing potentially injurious loading in both time and frequency domains. These findings offer practical guidance for the ergonomic design of sports flooring and training environments.

 Microgravity simulators, which provide both static and dynamic environments closely resembling real weightlessness, are of significant interest to space medicine, sports medicine, rehabilitation specialists, occupational therapists, and sports science experts. The primary aim of this study was to introduce a designed microgravity simulation treadmill for training in variable gravity conditions.

To build this device, the following components were used: a horizontal restraining surface that supports the user in a horizontal position, a supporting chassis that holds both the vertical treadmill belt and the horizontal supporter, six elastic straps for lower limb restraints (thigh and leg), a protractor that indicates the angle of the user's horizontal position relative to the ground and the exact amount of weight reduction due to applied gravity, and a rotating vertical treadmill belt, which is vertically oriented in this device, unlike traditional treadmills.

After designing the device, it was compared with similar devices based on the relevant physical laws, and its reliability and validity were assessed.

The results of this research, considering the specific feature of the microgravity simulation treadmill designed for training in variable gravity conditions, which allows for the creation of environments with varying weights, recommend its use for walking and running on a treadmill in weightless and microgravity environments. Additionally, this device can be utilized for research in the fields of rehabilitation, space medicine, and paramedicine.

The deadlift is recognized as a foundational exercise in bodybuilding and a pivotal component in powerlifting competitions. The present study sought to compare the coordination and joint angles of the lower extremities in elite male athletes while performing conventional and sumo deadlift techniques.

Fourteen elite male athletes participated in this study, performing two deadlift techniques at 70% of their one-repetition maximum for six repetitions. Kinematic data were collected using seven high-speed cameras and analyzed with OpenSim software. A dependent t-test was conducted to compare the mean joint angles and continuous relative phase across 10 phases in both the sumo and conventional techniques.

Significant differences were observed in the coordination of the hip, knee, and ankle during the initial, middle, and final phases of both techniques. Additionally, lower limb joint angles showed significant differences between the two techniques.

The results of this study revealed significant differences between the Sumo and conventional deadlift techniques in terms of lower limb joint angles and continuous relative phase changes. Therefore, athletes and coaches are advised to select the more appropriate deadlift technique during training and competition based on the athlete's fitness level, training goals, and required muscle involvement. Due to the greater hip abduction angle and joint coordination in the initial stages of the Sumo technique resulting in increased activation of the stabilizing muscles and a broader base of support the Sumo Deadlift is recommended for novice athletes.

This study aimed to investigate and compare the postural and musculoskeletal status of male and female athletes on the Iranian national shooting team. Identifying potential abnormalities and understanding gender-specific differences within this elite population can help inform necessary strategies for improving and maintaining musculoskeletal health, as well as optimizing athletic performance in shooting.

This applied, cross-sectional, and comparative study was conducted on 32 athletes (16 females and 16 males) from the Iranian national shooting team, each with at least five years of membership and national championship titles. Postural and musculoskeletal abnormalities—including lateral head deviation, uneven shoulders, scoliosis, lateral pelvic tilt, ankle eversion, forward head posture, kyphosis, sway-back posture, abdominal ptosis, lumbar lordosis, genu varum, genu valgum, pes planus, pes cavus, and intoeing—were assessed using the New York Posture Rating Chart, a posture grid, a plumb line, and calipers. Data were analyzed using descriptive statistics and the Chi-square test, with significance set at P ≤ 0.05.

A statistically significant difference was observed between male and female athletes only in the prevalence of lateral head deviation (P = 0.025), which was more common among males. No significant gender differences were found in other postural or musculoskeletal abnormalities. Most athletes exhibited normal posture in indicators such as scoliosis, kyphosis, and lateral pelvic tilt. However, conditions like lumbar lordosis, genu varum, and pes planus were observed in both groups, though without significant gender-based differences.

Elite male and female athletes of the Iranian national shooting team generally demonstrate favorable postural and musculoskeletal health. Nevertheless, the higher prevalence of lateral head deviation in males and the presence of abnormalities such as lordosis and lower limb deviations in both sexes merit attention. Regular screening, early detection of abnormalities, and implementation of targeted corrective interventions are essential for injury prevention, health maintenance, and performance enhancement in competitive shooters.

Since identifying the best way of performing the Judan Mai-Mawashi-Geri technique is one of the concerns of coaches and karatekas, the aim of this study was to compare the selected kinematic variables of four methods of implementing the Judan Mai-Mawashi-Geri technique by elite male karatekas.

Eighteen elite male kumite practitioners voluntarily and purposefully participated in this study. Nine markers were attached to the anatomical points of the hitting foot and the four methods of implementing the Judan Mai-Mawashi-Geri technique were filmed by three Hero3 cameras at an imaging speed of 240 Hz. Using SkillSpector software (version: 1.3.2), the resultant of the peak velocity of the lower limb joints, total distance, total velocity, and total acceleration was directly obtained. The one-way analysis of variance and the Bonferroni post-hoc test (p≤0.05) were used with SPSS software (version: 22) for statistical analysis due to the normality of data distribution.

The results showed a significant difference in the four methods of performing the Judan Mai-Mawashi-Geri technique in the peak velocity of the pelvic, knee, and ankle joints as well as total distance, total velocity, and total acceleration.

According to the results، the first method of execution، which starts in the first phase with 90 degree hip flexion (knee lift)، due to high speed and the possibility of scoring in the shortest appropriate time interval، against other tactics, Due to the closure of the opponent's attack route، Dai and Deashi can be recommended as a more efficient technique to the Athlete of the Kumite.

 Over the past decades, various types of eccentric exercises have been developed and used for facilitating improvements in musculoskeletal function and prevention or rehabilitation of muscle and tendon injuries. One of these exercises is the forward lunge, which is broadly used within the sports community amid training and recovery as it is better suited to the movement patterns of everyday tasks and different sports, activates multiple muscle groups simultaneously, and requires less specialized equipment. Various types of forward lunges have long been used when prescribing exercises for the lower extremities depending on a person's specific needs. In recent years, instability resistance training has gradually gained importance over traditional type in the field of sports training and fitness activities because of its simplicity (since it requires only body weight as a load), its specificity, and its high transferability to actions in athletic competition. Performing closed-kinetic-chain exercises like forward lunge with an instability device such as TRX suspension trainer system can alter movement patterns and affect motor control requirements differently A review of the research background shows that despite the increasing tendency of people to use instability devices, not many studies have been conducted in this area and most research has been done in the area of muscle activity, while there is no study on movement patterns or joint coordination, and due to the lack of information or mixed results [2,4], the different aspects of this way of exercise are still in an aura of uncertainty, leading to confusion for instructors or clinicians when designing exercise programs. Therefore, the aim of this study was to analyze coordination of the lower limb joints in performing forward lunge with and without using TRX.

A sample of 22 recreationally active female adults (mean height 164.9 ± 4.2 cm; mean body weight 60.6 ± 8.4 kg; mean age 25.45 ± 5.2 years) was recruited through a convenience sampling approach. Upon arrival at the laboratory, a 15-minute session of warm-up exercises was conducted and reflective markers (14-mm spheres) were placed (with double-sided tape) bilaterally over the landmarks [3]. Then, the random allocation of performance order was applied to each participant, who completed three repetitions of each exercise including conventional forward lunge, forward lunge by placing hands or foot inside the TRX rope. While performing exercises, kinematics of movements were collected using an 8-camera motion analysis system at 250 Hz (Oqus 5+, Qualisis). Analyzing motion data was conducted using The MATLAB software (The Mathworks Inc., Natick, MA). The lower limb was modeled as a composition of four fixed rigid segments, namely the pelvis, thigh, leg, and feet. Middle repetition of each exercise was interpolated and normalized to 100% of the movement cycle using spline. Then, angular displacement and velocity, range of motion, continuous relative-phase (CRP) angles and coordination variability of the joints of right leg of the subject, which correlates with the leading leg in all variations of forward lunge were calculated based on previous researches. In order to conduct a comparison of obtained values across different joints/exercises/phases repeated measures analysis of variance was employed. A post-hoc analysis was conducted utilizing Tukey's multiple comparison tests in order to identify notable variations. All statistical procedures were conducted using the SPSS platform for Windows (version 24. 0, SPSS Inc., located in Chicago, IL) and the predetermined level of significance was set at P < 0.05 for all statistical tests. 

The obtained results show that knee range of motion is greater than hip and ankle range of motion in all exercises, but FLL shows decreased knee and ankle range of motion and increased hip ROM. However, no significant interaction between exercises was found. RMS values of angular velocity for lower extremity joints across demonstrates higher angular RMS values for hip and lower values for knee and ankle in comparison of FLL with other variations. That means the hip moves faster than the knee and ankle when doing the FLL exercise. The difference in angular velocity of joints between FL and FLH was significant. RMS and MARP values of CRP couplings show an in-phase mode during 100% of movement cycle. Analysis of coordination variability (CV) in sagittal plane for the joints shows a significant difference between exercises and phases.

The study analyzed the displacement curves and found similar patterns in all three types of lunges, with FLL targeting the hip and FLH targeting the foot flexors. While all three types of lunges are recommended for improving knee joint range of motion and muscle function, FLL is recommended for improving hip extensor function and FLH for improving foot flexor function and ankle joint range of motion. Also an in-phase movement is found for all three types of lunges for the hip/knee, hip/ankle, and knee/ankle joint pairs during the entire cycle of motion in the sagittal plane. The study also found that closed-kinetic chain exercises require more synchronized joint movement, while open-kinetic chain exercises allow for more independent movement. The study suggests that closed-kinetic chain exercises are more effective for improving lower limb muscle function.

The optimal execution of sports skills results from the complex interaction of anthropometric, biomechanical, physiological, and psychological factors. It is crucial to understand the key indicators of each of these factors in male and female elite shooting players to identify, discover, and support talents, as well as design appropriate training programs. This can lead to better performance, success, and decreased injuries.

The present study compares key anthropometric, biomechanical, physiological, and psychological factors in male and female elite shooting players.

Iranian national shooting team members, n = 32 (16 female shooters and 16 male shooters), were recruited to participate in this study. They underwent an examination to assess and compare their main anthropometric (weight, height, limb length, limb height, limb widths, limb circumferences, body composition, and subcutaneous fat percentage), biomechanical (static balance, speed, acceleration, agility, leg power, abdominal muscle strength and endurance, reaction time, and flexibility), physiological (heart rate, cardiorespiratory fitness), and psychological indicators (basic psychological skills, psychomotor skills, and cognitive skills). The principal component analysis (PCA) statistical method was used to determine the principal components of the evaluated indicators, followed by the independent t-test statistical method to compare the two groups of males and females (P ≤ 0.05).

Significant differences were found between male and female shooters, including anthropometric measurements (such as waist circumference, knee circumference, forearm length, head circumference, arm length, hand length, arm circumference in contraction, arm circumference at rest, and height), biomechanical attributes (like agility, speed, abdominal muscle endurance, and finger reaction time), physiological indicators (including maximum heart rate and maximum oxygen consumption), and psychological factors (basic skills) (P ≤ 0.05).

According to the research findings, it is crucial to segregate talent search and development programs for shooting sports into separate groups for men and women. Coaches should monitor athletes during the off-season because there are differences between genders in anthropometric measurements, biomechanical traits, physiological parameters, and basic psychological skills. Furthermore, when designing an annual training schedule, it is essential to consider gender differences and tailor workouts to the distinct strengths, abilities, and characteristics of each gender to improve performance in competition.

The development of a standard motion capture system is needed since the measurement of temporomandibular disorders is time-consuming and costly using laboratory tools.

The current study aimed to investigate the mandibular kinematic variables using a regular mobile phone and the motion analysis system.

In this quasi-laboratory and comparative study, ten healthy individuals participated, and three mobile cameras, nine red markers, and Kinovea software were also used to investigate the mandibular kinematic variables. Nine light reflective markers were used to check the sensitivity, accuracy, and reliability of the proposed system. The motion was analyzed using seven motion analysis infrared cameras and Qualisys Track Manager (QTM) software. Two other raters analyzed the kinematic variables obtained from the mobile to measure intra- and inter-rater reliability.

Pearson’s correlation coefficient was obtained at 0.98, 0.75, 0.98, and 0.96, showing a high correlation. The accuracy and reliability validation tests showed an average error and an accuracy of 0.156 mm and 95%, respectively, with a mobile phone. The Intra Class Correlation coefficient showed a high internal correlation in the mentioned confidence interval (0.98 and 0.81, and 0.96 and 0.97). The intraclass correlation coefficient method also showed 97% inter-raster reliability. 

Mobile phones as a new system can evaluate the kinematic variables of mandibular disorders with appropriate accuracy and reliability.

The present study aimed to investigate the effect of the corresponding movement of the upper limb and the lower limb on the three-dimensional maximum mechanical power of the hip joint during walking.

30 healthy women walk at their chosen speed in two normal situations and the state of simultaneous and corresponding movement of the upper and lower limbs on the path of the force plate and in front of the motion analysis cameras. Based on the output data of the high-power devices, the mechanical strength of the right and left hip joints of the subjects was estimated in two situations and analyzed by paired t-test.

Except for the mechanical power produced by the right and left hip in the sagittal plane and the absorbing mechanical power of the left hip in the frontal plane, other variables of the mechanical power of the hip did not show significant differences in the three-dimensional plane.

The swing of the arm as a movement corresponding to the lower limb while walking does not have a direct effect on the mechanical power of the hip joint, and the main importance in this context is the existence of this swing due to the discharge of force and energy from the ground, either in the form of creating a corresponding movement or not. The movement is inconsistent.

The way we walk and the symmetry of various joints in the lower limb, particularly the knee, which is crucial for movement and weight-bearing, can change due to immobility and splinting of the upper limb. Therefore, this research aimed to conduct a symmetry analysis of the three-dimensional maximum mechanical power of the knee joint during walking while using an upper limb splint with a sling in young women.

This study employed a quasi-experimental and cross-sectional design. All research participants provided written consent to participate after being informed about the study's details. Ethical approval was obtained from the Kinesiology Research Center of Kharazmi University. Thirty healthy female subjects met the entry and exit criteria, which included having a dominant right limb and no history of orthopedic or neurological disorders. Participants walked along a force plate in three different conditions: normal, dominant upper limb splinting, and non-dominant upper limb splinting, all while being recorded by motion analysis cameras. Based on the obtained kinetic and kinematic outputs, the mechanical power value of the dominant and non-dominant knee of the subjects was estimated in three situations to compare the three-dimensional average mechanical power of the knee joint in each of the circumstances. Independent t-test was used at a significance level of P≤0.05.

The results showed that none of the values related to the knee joint's three-dimensional production and absorption power in the right and left limbs are significantly different.

The principle of symmetry in the knee joint is established between all three positions of dominant and non-dominant upper limb splinting. Since mechanical power is one of the important biomechanical criteria and contains kinetic and kinematic information at the same time, it may be concluded that the biomechanical symmetry of the knee joint is maintained in immobility states of the upper limb and these joint plays a more controlling role in walking.

 Flatfoot, as a three-dimensional foot deformity can cause alterations in motor function. Different methods, such as exercises, orthotic insoles, and specialized shoes, have been proposed to manage this condition. The present study aimed to compare the effects of orthotic insoles, shoes, and taping on the frequency content of ground reaction forces (GRFs) during walking in athletes with flexible flatfeet.

In this quasi-experimental study, 15 male athletes aged 18-25 years with flexible flatfeet (age: 21.78 ± 2.07 years; height: 1.78 ± 0.07 m; weight: 80.28 ± 8.23 kg) with a history of regular fitness training for at least 6 months participated. The GRF data were collected using a force plate under five walking conditions: shoes (relaxed-fit, breathe-easy Skechers) + insoles (ethylene vinyl acetate), barefoot, shoes, taping, and shoes + taping. The frequency content of the GRFS was then calculated. To compare the frequency content among different walking conditions, repeated measures ANOVA was used. P≤ 0.05 was considered statistically significant.

 The results showed significant differences between the various walking conditions, with the greatest significant reductions in the variables of 99.5% power frequency, median frequency, frequency bandwidth, and mean frequency in the shoes and shoes+ taping conditions (P<0.05). The reduction in frequency content was particularly prominent in the mediolateral direction.

 The use of shoes can result in a greater reduction in the frequency content of GRFs during walking in athletes with flexible flatfeet compared to taping or barefoot walking. Therefore, relaxed-fit, breathe-easy Skechers are recommended for enhancing motor performance in athletes with flexible flatfeet.

Walking is a complex activity that involves multiple parts of the body, including the lower limb, upper limb, trunk, head, and neck. Contrary to popular belief, walking is not solely related to the forward movement of the legs. Biomechanical analysis, especially in terms of mechanical power, is an essential aspect of gait studying. The study aims to explore how altering arm swing speed affects the 3D maximum mechanical power of the lower limb while walking.

In this study, 30 healthy women walked on a force plate path in front of cameras in three states of normal upper limb swing, fast upper limb swing, and slow upper limb swing. The calculation of muscle power in each lower limb joint and plane is based on the product of the joint moment and its angular velocity. The average mechanical power of the joints was compared using the repeated measurement test (P≤0.05).

The results showed that changing the swing speed of the arm has a significant effect on all absorption and production parameters related to the mechanical power of the lower limb joints.

In conclusion, any change in arm movement during walking can affect movement, balance, and gait biomechanics.

Many studies have investigated the effect of mechanical power on the symmetry and asymmetry of the lower limbs and have discussed the differences in the values of this parameter between the two limbs. Additionally, some studies have investigated and analyzed the types of mechanical power (propulsion and control) in joint movements. However, no study has yet examined and compared the muscle mechanical power among different joints of each limb, particularly the dominant leg. Therefore, the present study aimed to compare the three-dimensional mechanical power of the dominant lower limb during walking.

Thirty female subjects were asked to walk at their chosen speed and barefoot along the path of the motion analyzer cameras and on the force plate so that the three-dimensional mechanical power of each lower limb joint could be recorded using the obtained data. One-way analysis of variance (ANOVA) and Bonferroni's post hoc test were used to compare the values of mechanical muscle power variables at a significance level of P≤0.05.

Among the peaks of mechanical power of the dominant lower limb, the highest peak belonged to A2S, and the lowest belonged to K2T. Additionally, the most significant difference was observed between the average of some parameters such as H1S and other peaks, while the lowest average difference was observed between the averages of H2F and H1T and other mechanical power peaks.

Therefore, it can be concluded that there is a relationship between the peaks of mechanical power of the hip, knee, and ankle joints of the dominant lower limb. Among these peaks, the second peak of the ankle has the highest mechanical power, while the second peak of the knee has the lowest mechanical power.

The fencing lunge is one of the most common and fundamental attacking moves in fencing. The aim of this study was to provide kinematical compare of upper extremity among elite female and male senior fencers when performing a lunge.  Four female and four male members of Iran National Team were selected as research sample. The participants were filmed when performing a complete lunge with a camera of 300 Hz sampling rate to evaluate kinematical parameters. The student's-t test revealed that elite male fencers had significantly shorter reaction and movement time comparing with elite female fencers. No major differences in other kinematic parameters indicate that elite male and female fencers performed lunge in similar way. The final conclusion of this study is that the existing differences in time of lunge technique may suggest the need for alternative training strategies to prepare fencing athletes.The examination of the kinematic analysis of the upper body in male and female elite fencers demonstrated that the dissimilarity in the execution speed of the lunge technique between the two genders cannot be accounted for by kinematic changes in joint movements. The differences highlighted in this study can serve as a basis for formulating distinct training and coaching strategies, with the aim of better preparing athletes for decision making and quick movements.

 Cardiovascular diseases are among the most common causes of death in the world. The prevalence of cardiovascular diseases increases with older age. Using cardiac exercise training to rehabilitate the heart after heart disease creates functional and structural adaptations in the patient’s cardiovascular system, reducing mortality from related diseases. Therefore, this study aimed to investigate the effect of two aerobic and combined exercise training methods on heart function capacity in middle-aged male patients after bilateral femoral artery coronary bypass grafting surgery. 

In this quasi-experimental study with a pre-test-post-test design, 68 middle-aged male patients (Mean±SD age: 56.19±1.26 years) were studied after bilateral femoral artery coronary bypass grafting surgery. The subjects were randomly and availably divided into 3 groups: Aerobic (n=20), combined exercise training (aerobic+resistance) (n=20), and control (n=28). The subjects in the intervention groups performed 8 weeks of training, 3 sessions per week. Each training session in the aerobic and combined groups was performed for 40 minutes with the intensity of 70-85% heart rate reserved and 60 minutes with the intensity of 40-80% of one repetition maximum for each patient. Levene’s test, multivariate analysis of variance (MANOVA), and Bonferroni statistical tests were used to analyze the obtained data at the significance level of P≤0.05.

The one-way MANOVA test showed that functional capacity, ejection fraction and maximal oxygen consumption increased significantly after aerobic and combined exercise training compared to the control group (P<0.05). However, the Bonferroni post hoc test showed no significant differences between functional capacity, ejection fraction, and maximal oxygen consumption at post-test levels in aerobic and combined exercise training groups (P>0.05).

 The findings of this study show that both aerobic and combined exercise training can improve the heart functional variables in middle-aged male patients after bilateral femoral artery coronary bypass grafting surgery, and these improvement levels appear to be independent of the types of training.

 Concerning the effectiveness of training on people with chronic low back pain, the present study aimed to evaluate the effect of postural restoration institute (PRI) training on lower limb kinematics during walking in middle-aged subjects with discogenic low back pain.

 In this prospective observational quasi-experimental study, 42 people participated in three groups: people without low back pain (healthy group, n=14) and people with low back pain in two groups (intervention group, n=14; and control group, n=14). Kinematic data were recorded by 7 Qualisys cameras with a frequency of 100 Hz in the pretest and post-test. Analysis of variance with repeated measures was used in SPSS software version 23 at a significance level 0.05.

 The results showed that people with low back pain in the intervention and control groups walk with a slower velocity, lower cadence, and shorter step length than healthy individuals for both right and left limbs. However, after the PRI training, the intervention group showed a significant increase in those three variables. Furthermore, there were significant differences between the healthy group and the two groups of intervention and control in the range of motion (ROM) for the pelvis in the sagittal and frontal planes, the right hip joint in the horizontal plane, the right ankle in the frontal plane, the left hip joint in the sagittal and horizontal planes as well as the left ankle in the sagittal plane. After applying PRI, the differences between the healthy and the intervention groups regarding the pelvis ROM on the sagittal plane, the right ankle ROM on the sagittal plane, the left hip joint ROM on the frontal plane, and the left knee ROM on the sagittal plane were minimized and became insignificant.

 The present study’s findings confirmed the effectiveness of using PRI training in improving biomechanical indicators, such as the range of joint movements and increasing the velocity and step length of walking, to treat and manage the performance of people with discogenic chronic low back pain.

One of the issues that has been considered by sports researchers today is the claim of the effect of functional differences in the muscles of the core stability area on the results of kinematic and kinetic variables during the activities of athletes and non-athletes. The aim of this study was to investigate the interaction between lateral core stability area muscles function, ground reaction force and changes in center of mass to pressure in the Medio-lateral direction during gait according to the level of physical activity. Eighteen young men in two groups of 9 athletes and non-athletes participated in this study as subjects. Electrical activity of internal and external oblique muscles and information on the ground reaction force and changes in the center of mass to the presser were recorded during gait. The T-test was used to compare the results of the two groups at p ≤ 0.05. The duration of electrical activity of the external oblique muscle of athletes and non-athletes showed a significant difference (0.005), while no significant difference was observed in the electromechanical delay of the muscles. There was a significant difference between the two groups in the changes in center of mass to pressure of the Medio-lateral direction (0.041). The results of the study confirmed the interactive effect of the lateral core stability muscles and the behavioral pattern of changes in the center of mass to pressure and the ground reaction force in the Medio-lateral direction according to the level of physical activity during gait.

The present study aimed to determine the extent to which female athletes display asymmetrical or symmetry patterns in lower limb three-dimensional mechanical muscle power during gait. Thirty healthy female professional bodybuilders participated in his study. Their three-dimensional data of both lower extremities during walking was collected using a ten-camera Vicon motion capture system and two Kistler force plates. The peak mechanical muscle power of lower limbs in all three planes was calculated (P≤ 0.05). The results showed that except in the ankle joint, there were significant differences in third mechanical muscle power peaks of the knee and hip joints in sagittal plane (H3S, K3S), first and second mechanical muscle power peaks of knee joint in frontal plane (K1F, K2F), and second mechanical muscle power peak of hip joint in horizontal plane (H2T). In addition, the findings confirmed approximately 25% local asymmetry in the mechanical muscle power in the hip and knee joints between the right and left limbs.

Since the function of muscles, and subsequently the mandibular joint, is affected in patients with Bell's palsy, therefore, the evaluation of facial muscles and mandibular function in these patients can be effective in diagnosis, prevention, and treatment planning. The present study aimed to evaluate the degree of displacement and range of motion (ROM) of the mandible and the ability of the facial symmetrical muscles of patients with Bell's palsy.  

This was a quasi-experimental comparative study. The variables evaluated were mandibular movement in a vertical direction and side-to-side displacement. Ten patients with Bell's palsy and 10 healthy eligible volunteers participated in the present study. Three mobile video cameras (to record jaw movements), 9 color markers, Kinovea software, House-Brackmann index, Toledo protocol, and a specialized patient questionnaire were used. Descriptive and inferential statistics were used for data analysis, the Kolmogorov-Smirnov test was used to investigate the normality of data distribution, and independent samples the t test and paired samples t test were used to compare means.  

The maximum lateral on the sound side was 12.40 and 4.49 mm during lateral movements of the patients' mandible, while this value was between 12.30 and 3 mm on the involved side. There is a difference between the affected side and the nonaffected side in terms of the mean lateral movements of the patients' mandible. However, this difference in the mean ROM on both sides is not statistically significant. The maximum mouth opening in healthy individuals during mandibular movements was between 40 and 60 mm, while this value was between 25 and 50 mm in the patients with Bell’s palsy. This study shows a significant difference (P = 0.007) between patients and healthy individuals in terms of the mean of maximum mouth opening (P < 0.05).  

The results of this study showed that the ROM of temporomandibular joint (TMJ) of the patient is the same as that of normal subjects, but the side-to-side motion is more than normal which should be considered in rehabilitation treatments. The present study emphasizes the need to implement a mandibular kinematic evaluation protocol in patients with bell's palsy to prevent damage to the TMJ in the long term.

Nowadays, due to technological advances and sedentary or inactive lifestyle, non-communicable diseases have caused many health problems such as cardiovascular diseases. This study aims to examine the effect of two methods of aerobic training and concurrent training for cardiac rehabilitation on selected hemodynamic and biomechanical factors in older men with coronary artery disease.

This is a quasi-experimental causal-comparative study using the pre-test/post-test design. Participants were 24 older men with coronary artery disease, randomly divided into three groups of aerobic training, concurrent  training, and control. They first underwent cardiac assessment using the echo Doppler device as well as sports performance test. Then, they were referred to the biomechanics laboratory of the Physical Medicine Center to start cardiac rehabilitation training. After 8 weeks of training, they underwent post-test assessments. The mean and standard deviation were used to describe the data. The Shapiro-Wilk test was used to check the normality of data distribution and the Levene’s test was used to determine the homogeneity of variances. The paired t-test was used to assess between-group differences and independent t-test was used for assessing differences between pretest and post-test scores of the groups. The significance level was set at 0.05.

Significant improvement was reported in functional capacity, left ventricular ejection fraction (LVEF), and resting heart rate after both aerobic and concurrent training methods (P<0.05), but no significant difference in diastolic blood pressure and systolic blood pressure were observed (P>0.05). The improvements were more in the concurrent  training group.

Both cardiac rehabilitation methods (aerobic and concurrent  training) can improve functional capacity, LVEF, and resting heart rate of older mean with coronary artery disease, where concurrent  training is more effective.

The purpose of this study was to examine and compare the difference between inside kick, outside kick, toe foot kick and cheap kick with maximum effort, in some parameters associated with the electromyographic activity of the quadriceps muscle. Eight skilled collegiate soccer players volunteered as subjects in the study. These variables were included the average and maximum activation, activation time (AT), the time which the muscles reached to zenith activity (ZAT) and work (W). In order to calculate electromyography of selected muscles contain, RectusFemuris, VastusMedialis and VastusLateralis, ME6000 apparatus with 1080 Hz sample rate was used. Paired sample t-test was used to analyze data. The results indicate similarity between outside and toe foot kicks in average and maximum activity, activation time and work. thus there was no significant difference in electromyographic activity of the quadriceps muscles between these two kicks. But in many parameters, these two kicks were different with inside and cheap kicks. In a nutshell, according to the results, it can be said, quadriceps muscles during various kicks, adapting different trend of contraction which are dependent on the position of the muscles and limbs interaction during soccer kick. And outside kick could be created maximum stimulation in quadriceps.