razieh yousefian molla

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.

Lumbar hyperlordosis is a common problem among athletes, characterized by an excessive increase in the lumbar arch which can lead to chronic Low Back Pain (LBP). The central stabilizing muscles of the trunk are crucial for maintaining proper stability and alignment of the spine. Weakness in these muscles can increase the lumbar arch's severity and associated pain. This study aimed to investigate the correlation between the endurance of different groups of core stability muscles and pain in women athletes with lumbar hyperlordosis.

36 female athletes with lumbar hyperlordosis were randomly selected and examined. The study assessed the endurance of the different central stability muscles, including trunk flexors, extensors, and lateral flexors, using McGill tests. Additionally, the athletes' level of LBP was measured using the Visual Analog Scale (VAS). Data analysis used multiple linear regression to assess the correlation between muscle endurance and pain.

None of the endurance variables of the four central stability muscles are significantly associated with the pain of subjects with hyperlordosis (P≥0.05). According to the reported beta values, the endurance of the muscles of the trunk extensor, left lateral flexor, right lateral flexor, and trunk flexor have the greatest association with LBP of athletes with lumbar hyperlordosis (P≥0.05).

These findings suggest that increasing the endurance of the central stabilizing muscles, could not significantly reduce LBP in athletes with lumbar hyperlordosis, for this reason, there is no need to separate the strengthening of the core muscles to reduce LBP These results could be used to develop targeted exercise programs to correct posture and reduce pain in this population.

Biofeedback therapy is widely used as a treatment method for rehabilitating stroke patients. This study examines the effects of long-term hand biofeedback therapy on the upper limb function and quality of life of elderly people who have had a stroke. 

A total of 40 stroke patients were divided into a control group and an electromyography biofeedback training group. After two years of treatment, evaluations were performed to assess the impact of electromyography biofeedback training on upper limb function and quality of life for both groups. 

The results indicated that after two years of hand biofeedback, only the quality of life improved, while the function of the upper limb did not show significant changes (P≤0.05). 

Long-term use of the biofeedback exercise method in stroke patients primarily impacts their quality of life rather than significantly affecting the function of their upper limbs.

Context:

 This systematic review investigated the effects of plyometric exercise interventions on proprioception.

An electronic search was conducted in October 2022 across eight databases: PubMed, Scopus, ProQuest, Science Direct, Google Scholar, DOAJ, IEEE Xplore, and Cochrane. To be included in the review, studies had to meet all the established inclusion criteria. Twelve studies were included in the final analysis, and their quality was assessed using the Downs and Black checklist.

The review found that the included studies considered various plyometric training protocols and methods for assessing proprioception. Despite differences in training regimens and assessment metrics, the data consistently showed a positive effect of plyometric training on proprioception.

The review concluded that plyometric exercises improve proprioception, regardless of the specific type of training or assessment method used. A primary limitation identified was the scarcity of randomized controlled trials (RCTs) that focus on plyometric exercises and their impact on proprioception.

It is essential to analyze demographic characteristics to enhance the performance of the block jump skill based on the kinetics domain. For this reason, this study aims to analyze the relationship between jump height and the demographic characteristics of young volleyball players while performing block jumps based on kinetics.

This study included twenty-one young male volleyball players. Each player was instructed to perform 3 block jumps on a force plate using maximum power, and their jump height was estimated using a kinetics method. Moreover, the players’ demographic features, such as height and weight were also measured for the analysis. To determine the relationship between the players’ jump height and demographic characteristics,  a one-way linear regression statistical method was used.

No significant relationship was found between height and weight (demographic characteristics) and jump height. However, height had a higher factor loading with jump height, indicating more correlation with jump height than weight (P≤0.05).

To enhance the jumping and landing abilities of elite volleyball players, it is suggested that coaches, players, and specialists assess biomechanical performance through various means. Demographic characteristics can serve as useful indicators to improve performance. A thorough analysis of these indicators can significantly aid in achieving success in volleyball.

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.

Core stability training plays an important role in performance of youth volleyball players and is defined as a critical factor regarding prevention of the physical abilities and important characteristics of the volleyball players such as balance and jump performance. In this research, the effect of a Progressive Core Stability Program regarding Health Protection on maintenance of Balance and Jump Performance of Junior Volleyball Players during Coronavirus Pandemic has been investigated. After the second quarantine period in Iran, two jump tests (Serjent jump test and Three-step jump test) and static balance test (Romberg) were taken from each player. The players then performed a 12-week core stability training program in compliance with health protocols. Following that, post-test evaluation was recorded. There is a significant difference in all research variables (Sarjent jump test, Three-step jump test and Romberg equilibrium test) between pretest and post-test in junior volleyball players after 12 weeks of progressive core stability training with health protocols. Coaches, specialists in sports sciences and trainers can use progressive core stability exercises to maintain vital functions in volleyball players and emphasize their performance during quarantine.

The lack of coordination in body movements while walking is known as asymmetry. Excessive asymmetry in movement can be used to diagnose various diseases among individuals with and without pathology. Despite the wide variety of equations and formulas used to estimate symmetry and asymmetry, it remains unclear which equation is superior to the others. The present study aims to compare the equations to gain a better understanding of three-dimensional joint angle symmetry during walking and to select a more suitable equation for estimating symmetry in athletes. 30 healthy female athletes walked barefoot in front of 10 Vicon motion analyzer cameras along a 10-meter walkway to record three-dimensional angles of both lower limb joints. Then by independent t-test, the results of two equations of calculating the symmetry of the three-dimensional angles of the hip, knee, and ankle joints of the lower limbs were compared. The study's results revealed that there was no statistically significant variance in the lower limb symmetry when comparing the two distinct symmetry equations. coaches and sports professionals can use these findings to analyze the symmetry of athletes' movements and develop tailored training programs. Moreover, these assessments can aid in identifying and correcting any asymmetries to prevent sports-related injuries, as symmetry and the dominant leg are crucial for maintaining proper technique across a wide range of sports.

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 effect of gender differences on the occurrence and symptoms of stroke has always been considered and unclear. The purpose of this research is to investigate and compare the effect of a long-term traditional rehabilitation course on the knee function of women and men with stroke.

The present study was a cross-sectional study. The knee function of 10 women and 10 men stroke patients was measured at the beginning and end of two years of traditional rehabilitation programs. To compare the knee functions of two groups in the pre-test and post-test stages, the inferential ANOVA method and post-hoc Bonferroni tests were used (P≤0.05).

The results showed that there is no significant difference in the average knee performance of women and men with stroke before and after long-term rehabilitation (p=0.07).

Maybe we can conclude that gender is not an important factor in the field of knee rehabilitation planning and its results.

 Although immobilizing the upper limb is known to aid rehabilitation and improve symptoms for specific conditions, there is evidence suggesting that casting or splinting the upper limb can substantially alter walking biomechanics, including kinetics, kinematics, and spatiotemporal aspects.

 This study aimed to explore how unilateral casting of either the dominant or non-dominant upper limb affects the maximum three-dimensional mechanical power of the ankle joint during walking.

 In this quasi-experimental study, 30 healthy women (average age ± standard deviation: 29.5 ± 3.45 years) participated. They walked under three conditions: Without immobilization, with immobilization of the dominant upper limb, and with immobilization of the non-dominant upper limb, along a path equipped with force plates and cameras. The instantaneous muscle power at the ankle joint in each plane was measured. A repeated measures analysis of variance (ANOVA) was conducted to identify significant differences among the three conditions.

 Significant changes were observed in all parameters of maximum power generation and absorption at the ankle joint across all planes when walking with the dominant and non-dominant upper limbs splinted (P ≤ 0.05).

 Considering that muscle power is a crucial biomechanical parameter during walking, the observed alterations in this parameter due to upper limb splinting highlight the need for awareness to prevent potential walking difficulties when using upper limb braces.

Depression is a common problem after stroke, with a high prevalence. Multiple studies have suggested that biofeedback therapy can effectively treat depression without causing side effects. This research aims to investigate the long-term impact of biofeedback therapy on depression in stroke survivors.

A quasi-experimental study was conducted with 40 stroke patients who were divided into a rehabilitation control group and a rehabilitation group that underwent long biofeedback electromyography exercises. All patients were assessed for their level of depression at the start of the study and again after two years of treatment, after completing occupational therapy sessions with and without biofeedback intervention. Statistical analysis was performed using paired t-tests and correlated t-tests with a significance level (P≤0.05).

In both control and intervention groups, no significant differences were observed in the level of depression between the pre-test and post-test stages. However, a crucial difference was observed between the intervention and control groups after using biofeedback. The average depression in patients who used long-term biofeedback decreased after two years compared to the control group (P≤0.05).

Long-term utilization of biofeedback therapy impacts the depression levels of stroke patients. This method is highly recommended as a complementary approach to conventional rehabilitation.

The successful performance of block skills is crucial for volleyball players, requiring efficient techniques that optimize time, movement, and vertical jump. The purpose of the present investigation was to compare the kinetic temporal phasic differences between middle and side blockers among elite volleyball players during block jump. 

Seventeen junior male volleyball players, consisting of eight middle blockers and nine side blockers, participated in this research. The evaluated skill was the block jump ability. Data collection involved calibrating a force plate (Kistler® 1000 Hz). An independent t-test was used to compare mean values between the two groups during jumping (p<0.05). 

The results indicated no significant differences between middle and side blockers in terms of time and force during the amortization phase. 

These findings provide valuable insights into monitoring time and force variables among middle and lateral blockers. Trainers can utilize these results to tailor task-specific training programs that optimize performance outcomes.

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.

Understanding the biomechanical performance of the lower limb joint during running is of the utmost importance for enhancing our current understanding of high human performance, as well as for identifying potential factors that may be associated with injuries. Given that the mechanical work of the lower limb joints conveys crucial information about joint function, the objective of the present study was to examine the impact of increasing running speed on the mechanical work of elite male runners.

The current study is an observational cross-sectional study.28 healthy male elite runners aged 22 - 51 years ran on a treadmill with a force plate in the middle of the walk-way, at three different speeds, 2.5, 3.5 and 4.5 m/s respectively, and the data related to the mechanical work of the lower limbs were recorded and extracted. Also, in order to compare the averages of the Hip, Knee and Ankle mechanical work variables, ANOVA repeated measurements method with Bonferroni post hoc test was used.

It was found that increasing the speed leads to a significant difference in the mechanical work of the joints of the lower limbs including hip and ankle in both absorption and production phases(P<0.05) except in the knee joint at a speed of 3.5 to 4.5 in positive mechanical work (P=0.121).

Considering the biomechanics of running is very important as a basic skill that every person performs during his life. The mechanical work aspects of the hip, knee, and ankle joints during increased running speed may potentially provide a biomechanical explanation for these clinical observations.

This study aimed to investigate the effect of chronic ankle instability on coordination and variability of coordination of lower limb joints during running. 20 active male subjects (10 subjects with chronic ankle sprain and 10 healthy subjects) started running on the treadmill with connected sensors at a gradual speed. Information about the coordination and variability of 10 steps of each subject in the joints of the lower limbs was extracted in the sagittal plane of all three joints (hip, knee, and ankle) as well as the transverse plane of the ankle. Finally, an independent t-test was used to analyze the statistical analysis at a significant level of (P <0.05). The results showed that coordination at the initiation of the stance phase was significantly lower in the group with chronic ankle sprain than in the healthy group. The coordination of the hip-knee, hip-to-ankle, and knee-to-ankle joints are more different in injured people than in healthy people at the initiation of the stance phase running, so the coordination of these joints is reduced in the sagittal plane of subjects with chronic ankle sprain. Also, the coordination of the knee joints to the ankle in the frontal plane of the injured group is greater than the healthy group. Chronic ankle sprain injury has caused this difference in the pattern of coordination during the stance phase of running, so that the central nervous system of the body, under the influence of fear of re-injury, designs the movement of the ankle joints relative to the knee to minimize the risk of injury.

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.

Running is known as one of the most popular sports for which there is no time and space limit. Recently, due to lifestyle changes, the use of treadmills for walking and running has increased. However, the biomechanical differences in coordination between running on a treadmill at different speeds have not been sufficiently addressed. The aim of this study was to investigate the effect of increasing running speed on three-dimensional changes of lower extremity joint angles in the open motor chain and swing phase.

28 elite runners participated in this study. Subjects ran on an equipped treadmill while kinematic running data was recorded for 30 seconds through a three-dimensional 12-camera motion recording system at speeds of 2.5, 3.5 and 4.5 m / s. Data were normalized based on the subjects' body mass as well as 101 time points in the running cycle. The normality and homogeneity of variance of the dependent variable were tested using Bartlett and Leven’s tests. Repeated measurement test was performed to measure the angles of the pelvis, knee and ankle between the dominant and non-dominant lower limb joints in the running swing phase.

In the range of motion of hip, knee and ankle joint, there were significant differences among all the three speed rates of 2.5, 3.5 and 4.5 on all planes.

Changes in the angle and range of motion of the hip, knee and ankle joints are significantly greater in the swing phase as the running speed increases. Due to the fact that in high-speed running, the stability of the body decreases, the central nervous system commands to increase the range of motion of the angle of the mentioned joints to regulate the structure of the body and reduce the instability in response to the applied disorders. The results also show that the ankle joint, as the closest joint in contact with the ground, helps to run faster and more efficiently by increasing changes in the angle and range of motion of the ankle joint during running, and by reducing the time of foot contact with the ground at each step. It can be concluded that this point is effective in increasing speed.

Investigating and understanding the relationship and correlation between functional movement screening (FMS) and anthropometric characteristics play a significant role in predicting and preventing injury. This study investigated the relationship between FMS and anthropometric characteristics in the Iranian national team's teenage volleyball players. 22 elite youth volleyball players who were members of the national adolescent volleyball team of the Islamic Republic of Iran participated in this research. Also, two demographic characteristics and FMS were examined. The Pearson correlation test was used to investigate the relationship between the demographic variables and the FMS score. There was a significant positive relationship between "in-line lunge with upper limb balance, shoulder mobility with active straight leg raise, fat mass index with fat ratio to SM, Body Mass Index (BMI), Total Body Fat (TBF%), Visceral Fat Index (VFI), fat-free mass with fat-free mass index. Bone Mineral Content (BMC), Basal Metabolic Ratio (BMR), the ratio of fat to SM with TBF% and VFI" and “weight with BMI, BMC, and BMR, and BMI with VFI, BMR, and Upper Limb Balance" and "TBF% with VFI" and "BMC with BMR" and "TBW% with SM%" and "body balance with TBW%, SM%, and Upper Limb Balance”. Based on the analysis of the obtained results, it can be suggested that FMS test results and anthropometric indices can be useful in the initial assessment and prediction of people's susceptibility to functional-motor injuries. Also, athletes' functional movement patterns and body composition are different according to their sport and position. Therefore, it is necessary to pay attention to the positive points of the athlete's performance in his specialized sports field and functional movement disorders in young people, which may help to reduce injuries and improve sports performance.

Attention can be paid to the biomechanical characteristics of running since the speed of running varies. The aim of the present study was to investigate the effects of increasing running speed on the three-dimensional kinematics of the lower limb joints in the stance phase.

The research was quasi-experimental. 27 volunteer subjects ran on a treadmill and the kinematic and kinetics data were collected through a three-dimensional system at three speed levels (2.5, 3.5, and 4.5) m/s. kinematics and kinetics data were recorded by 12 cameras (120 Hz) and force platform (150 Hz), respectively.   The stance phase was derived according to the ground reaction Force value of the force platform. Hip, knee and ankle kinematics including peak of the absolute angles in three dimensions and three speeds were calculated for further analysis. Repeated measurement with Bonferroni post Hoc tests were employed to investigate the differences between the variables in three dimensions using SPSS software (P <0.05).

The results showed that during increasing speed, significant differences were observed in frontal (2.5 & 3.5, 2.5 & 4.5 m/s) and sagittal (2.5 & 3.5. 2.5 & 4.5, 3.5 & 4.5 m/s) planes in hip as well as only in transverse (2.5 &4.5, 3.5 & 4.5 m/s) plane for knee. No significant differences were obvious in peak of ankle joints during increasing speed in all three planes.

The results of the present study showed that hip and knee joints are more susceptible to changes of kinematics behavior during running progressively. Ankle joint seems to be more stable during the progressive running situation. Coaches and athletes may also enhance their performance using the results of the present study.

The aim of this study was to investigate the effect of increasing running speed on motor ‎chain and kinetic ratio of lower limb joints‎.

The statistical population of this study consisted of healthy people and ordinary runners. A ‎group of 28 healthy male subjects, including runners who ran more than 20 km per week, ‎were selected via convenience sampling method as research sample. They were also fully ‎acquainted with running on a treadmill. Three-dimensional kinetics parameters of the lower ‎limb joints, hip, knee, and ankle, torque and the kinetic ratio of the minimum, maximum and mean values of these ‎joints at three different speeds 2/5,3/5 and 4/5 was measured by two important instruments, ‎the camera and the force plate. Shapiro-wilks test was used to check the normality of data ‎distribution and data analysis was performed using analysis of variance with repeated ‎measurements or repeated measure through SPSS software, version 22‎.

Based on the results obtained in this study, the torque ratio of hip to knee and thigh to ankle ‎joints was not significant in any of the anatomical plates and axes at three speeds (p≥0.05). ‎Also, the ratio of torque of knee joints to ankle in three speeds and three planes did not ‎show a significant difference ( p≥0.05)‎.

According to the results obtained in this study, it seems that with the knowledge of the ‎moment changes of the lower limb joints, practical solutions can be provided to reduce the ‎amount of damage when running, especially on a treadmill, to these 3 joints. ‎

The aim of this study was to present and discuss the knowledge gathered on various Achilles tendon injuries and to highlight the clinical implications for the evaluation and treatment of Achilles tendon injuries. Achilles injury is common in both athletes and non-athletes. Study design: Systematic review.

A search of 6 databases was performed using keywords related to Achilles tendon injury factors and a review of all usable manuscripts was performed.

One hundred and fifteen articles met the inclusion criteria. Among all the independent variables that were analyzed, age, obesity, athletes and normal people, professional or amateur sports, men and women, and Achilles tendon treatment methods were examined.

Comparison of the incidence of Achilles tendon injuries in sports and non-sports shows that the increased risk of Achilles tendon injuries in male athletes is higher than women, which has the opposite effect with age, and it can be concluded that Achilles injuries in both Men and women are generally almost equal.

Due to the paucity of information regarding the lower limb biomechanics in running at slow speed, as well as the concentration of most previous studies on a single movement plane, this study aimed to investigate lower limb joint kinetics with increasing running speed.

Twenty-eight runners were asked to stay on the treadmill at a bent velocity which was incrementally increased to 2.5 m/s, 3.5 m/s, and 4.5 m/s speeds. The three-dimensional joint moment and sagittal mechanical muscle power of the lower limb were calculated during the stance phase of running. Repeated measures analysis of variance (ANOVA) with Bonferroni post hoc test was used to examine the variables during running at various speeds.

The results showed that at the hip joint in the frontal plane, an adduction moment developed in the middle of the stance phase, and the highest peak adduction moment was obvious at the highest speed condition (4.5 m/s). Also, the time elapsed to peak in the highest speed condition was less than the others. In the transverse plane, although the 3.5 m/s-speed condition experienced the maximum external rotation peak moment, the 4.5 m/s-condition speed reached the internal status earlier than the two other speeds. In the sagittal plane, the highest speed condition showed the highest extension and flexion moments.

Increasing running speed in runners leads to more kinetic output and mechanical power gradient.