Mohamadreza Hatefi - Academia.edu (original) (raw)

Papers by Mohamadreza Hatefi

Movement & sport sciences, 2024

PLOS ONE

Background The application of the modified reactive strength index (RSImod) and isometric hamstri... more Background The application of the modified reactive strength index (RSImod) and isometric hamstrings to quadriceps (H:Q) torque ratio to monitoring the athletes’ performance is well established, but their relationship to each other still remains unknown. Therefore, the purpose of this investigation was to clarify whether there is a relationship between RSImod and the isometric H:Q torque ratio. Methods Twenty-one male recreational athletes (age, 24.89 ± 4.46 years; weight, 74.11 ± 8.66 kg; height, 179.78 ± 6.76 cm) volunteered to participate in this research. Their isometric H:Q torque ratio via hand-held dynamometer and jumping performance variables during the stop jump (STJ), double leg-drop vertical jump (DL-DVJ), and single leg-drop vertical jump (SL-DVJ) tasks were measured. Also, the RSImod was calculated by dividing the vertical jump height by the time to take-off. Pearson correlation coefficients were used to determine the relationship between the RSImod and jumping performa...

Journal of Experimental Orthopaedics

Purpose Tibiofemoral Varus Malalignment (TFRV) contributes to overuse injuries by altering lower ... more Purpose Tibiofemoral Varus Malalignment (TFRV) contributes to overuse injuries by altering lower limb biomechanics. Both Posterior X Taping (PXT) and Real Time Feedback (RTF), have each been recommended for subjects with TFRV as they are thought to enhance control of excessive tibiofemoral rotations. This paper evaluates this claim. Methods A total of recreational male 24 athletes with TFRV participated in the current study. Kinematic and electromyography variables of lower extremity were synchronously recorded on five consecutive repetitions of the single-legged-squat (SLS) and forward-step-down) FSD) tasks before and after applications of PXT and RTF. Results The subjects at post-intervention in RTF group exhibited decreased hip adduction during FSD, and decreased hip adduction and internal rotation during eccentric and concentric phases of the SLS; Additionally, we observed increased gluteus medius activity during eccentric phase of the SLS and FSD tasks. In contrast, subjects a...

Journal of Clinical Research in Paramedical Sciences, 2021

Background: Patellofemoral pain syndrome (PFPS) is one of the most common knee injuries in athlet... more Background: Patellofemoral pain syndrome (PFPS) is one of the most common knee injuries in athletes and non-athletes. Due to the pain and muscle inhibition, it is possible that the disorder has negative effects on joint position sense. Cryotherapy is one of the most common methods applied in sports injuries. Objectives: The aim of this study was to evaluate the effect of topical cooling with ice and cold spray on knee joint position sense of athletes with PFPS. Methods: In this quasi-experimental study, 30 athletes with PFSP were divided into two groups of cold spray and crushed ice application. The effect of cooling on joint position sense was measured by the target reconstruction method (30° of knee flexion) while standing. In order to analyze the data, SPSS 23 and statistical tests of Shapiro-Wilk, paired t-test, and independent t-tests were used. The absolute error of 30° knee flexion angle reconstruction immediately after cryotherapy was significantly higher than before it in v...

Background: Gluteus medius muscle (Gmed) dysfunction has been confirmed as a functional defect in... more Background: Gluteus medius muscle (Gmed) dysfunction has been confirmed as a functional defect in subjects with Genu Valgum Deformity (GVD). In relation to these subjects, increase Gmed activity without synergist muscles dominance is considered as part of a specialized exercise program. Methods: A total of thirty female recreational athletes with (n=15) and without (n=15) GVD participated in this study. Surface electromyography measured Gmed, tensor fascia latae (TFL), and quadratus lumborum (QL) muscles activity when subjects performed pelvic drop (PD) in three different positions of hip rotations with and without applied isometric hip external rotation force. Results: There were differences in muscle activity between GVD and healthy subjects. The Gmed/TFL and Gmed/QL muscles activity ratio altered when placing the hip in different rotation positions and applying isometric load. Conclusions: The lower extremity muscles activity is affected by GVD, and changing the positions of the ...

Ankle sprain is one of the most common injuries during a physical activity, which may lead to ins... more Ankle sprain is one of the most common injuries during a physical activity, which may lead to instability and affect athletes’ performance. The present study aimed to investigate the immediate effects of kinesiotape and wobble balance board trainings on ankle joint position sense of individuals with Functional Ankle Instability (FAI). A total of 48 male athletes with FAI voluntarily participated in this study and were stratified into four groups including kinesiotape, wobble board, combined, and control groups. The pre-test was performed by Position sense at angles of (Plantarflexion 10°and 30°) using a gyroscope. Following the intervention, the post-test was taken from the subjects. Four-way repeated measures Analysis of Variance (ANOVA) followed by the post hoc analysis with Bonferroni’s test was conducted to compare the groups. In addition, paired sample t test was used to assess the intragroup variable. The results indicated statistically significant differences in applying imme...

Scientific Reports

Gluteus medius muscle (Gmed) dysfunction has been confirmed as a functional defect in subjects wi... more Gluteus medius muscle (Gmed) dysfunction has been confirmed as a functional defect in subjects with Genu Valgum Deformity (GVD). The purpose of this study was to determine whether the change in the positions of hip rotation and applying isometric hip external rotation during pelvic drop (PD) can affect muscles activity in subjects with GVD. A total of thirty recreational female athletes with (n = 15) and without (n = 15) GVD participated in this study. Surface electromyography measured Gmed, tensor fascia latae (TFL), and quadratus lumborum (QL) muscles activity when subjects performed PD in three different positions of hip rotations with and without applied isometric hip external rotation force. There were differences in muscle activity between GVD and healthy subjects. The Gmed/TFL and Gmed/QL muscles activity ratio altered while placing the hip in different rotation positions and applying isometric load. The lower extremity muscles’ activity is affected by GVD, and changing the p...

Journal of Rafsanjan University of Medical Sciences, 2020

Background and Objectives: Change in the lower extremity alignments in the frontal plane and musc... more Background and Objectives: Change in the lower extremity alignments in the frontal plane and muscle activation patterns during pedaling is associated with patellofemoral pain (PFP) and iliotibial band (ITB) syndrome. Therefore, the aim of the present study was to determine the effect of band loop on kinematic and electromyography of lower extremities during pedaling. Materials and Methods: In this descriptive study, Kinematic information of the lower extremity and the electromyographic activity of muscles of 30 male students (normal=15, Genuvarum (GV)=15) in the Movafaghian Clinic in Tehran were recorded during pedaling with and without band loop in 10 pedaling cycles of last 30 seconds. Independent t-test and paired t-test were used to analyze the data. Results: The results showed a significant difference in the gluteus medius (Gmed) muscle activation (p=0.001) and Gmed/tensor fasciae latae (TFL) activity ratio in both groups (normal p= 0.042, GV p= 0.045), onset of TFL (p=0.007) and offset of Gmed activity (p=0.018) in the normal group, and the onset of Gmed muscle (p=0.048), offset of Gmed (p=0.047) and mean knee abduction angle (p=0.047) in the GV group. Also, the results showed a significant difference in TFL activation with and without the loop across the two groups (with loop p= 0.001, without loop p= 0.003) and the mean (p=0.021) and maximum knee abduction angle (p=0.027) without loop between the two groups. Conclusion: Pedaling with loop band can be an effective method to increase the function and activation of Gmed muscle while decreasing TFL, improving knee kinematics in the frontal plane and knee stability to prevent injury in the normal and GV groups.

Journal of Sport Biomechanics, 2019

Objective Numerous abdominal exercises with Swiss ball are used to improve core stability with st... more Objective Numerous abdominal exercises with Swiss ball are used to improve core stability with strengthening and rehabilitation goals. It is claimed that the stability exercises have a greater impact on core muscle activation, but the validity of this claim is still in doubt. Moreover, there is no comprehensive study on the comparison of the core muscles activity in different core stability exercises. Therefore, the purpose of this study was to compare the Electromyography (EMG) activity of core muscles while performing side plank on stable and unstable (Swiss ball) surfaces. Methods Fifteen male students of Allameh Tabataba’i University were selected for the study based on inclusion and exclusion criteria. The EMG activity of gluteus medius, rectus abdominis, external oblique, and internal oblique muscles in subjects was recorded while performing side plank exercise on a fixed surface and a Swiss ball (2 sets of 5 seconds with a 30-second rest interval). Results There was a signifi...

International Journal of School Health, 2020

Background: Postural control can be affected by hyperlordosis and the effect of core training on ... more Background: Postural control can be affected by hyperlordosis and the effect of core training on postural control has yet to be established in students with hyperlordosis. Therefore, the aim of this study was to investigate the effect of core stabilization exercises on balance indices in girls with hyperlordosis. Methods: In this controlled laboratory study, we divided 32 girls (14-15 years old) with hyperlordosis inTehran schools into experimental and control groups in 2018. The experimental group received two core exercise sessions per week for a period of eight weeks. Before and after exercises, we evaluated the balance indices of center of pressure (COP) and time to stabilization (TTS). To analyze the data, statistical analysis of the t-test was used via SPSS software. Results: We observed significant differences in the COP indices of R.AP (P=0.038) and V.AP (P=0.001) and TTS indices of vertical (P=0.012), antroposterior (P=0.032), and mediolateral directions (P=0.001) before an...

BACKGROUND Change in the lower extremity alignments in the frontal plane and muscle activation pa... more BACKGROUND Change in the lower extremity alignments in the frontal plane and muscle activation patterns have been associated with lower extremity injuries. Therefore, to prevent injuries, many therapeutic protocols focus on find ways to correct dynamic knee valgus (DKV). METHODS Thirty-one recreational male cyclists with DKV (26.4 ± 4.5 years, 176.63 ± 7.51 cm, 75.81 ± 9.29 kg, 23.20 ± 4.15 kg/m2) volunteered to participate in this study. A motion analysis system and a surface Electromyography were used to collect ten cycles of three-dimensional kinematics and muscles activity during 2 min of pedaling in each of four testing conditions. The paired t-test was used for statistical analysis (p < 0.05). RESULTS The results indicated significant differences in VM (band = 0.029, no band = 0.031) and VL (band = 0.015, no band = 0.035) activation between workloads in each condition. Also there were significant differences in Gmed activation (0.5kg = 0.001, 2kg = 0.037), onset of Gmed (0....

Background: patellofemoral pain syndrome (PFPS) is one of the most common knee injuries, which is... more Background: patellofemoral pain syndrome (PFPS) is one of the most common knee injuries, which is caused by the abnormal position of patella. The present study was conducted to compare the effects of an eight-week training in both Total Resistance exercise (TRX) and physioball groups on the amount of pain and motor function of non-athletic women with patellofemoral pain syndrome. Methods: In this semi-experimental study, 30 non-athletic women suffering from patellofemoral pain syndrome were randomly divided into two groups. The first group performed TRX exercises (15 people), and the second group performed physioball exercises (15 people). Both groups received 3 practice sessions per week for a period of 8 weeks. The visual analog scale (VAS), pain scale and Kujala Patellofemoral questionnaire (KPQ) were employed before and after the exercise to assess the pain and motor function. Paired T-test and independent t-test were used. The significance level was considered as P≤0.05. Result...

Purpose The benefits of providing static stretching exercise targeting the hips in patients with ... more Purpose The benefits of providing static stretching exercise targeting the hips in patients with non-specific Low Back Pain (NSLBP) are not well established. The objective of the study was to verify the effects of static stretching on function, pain and range of motion on patients with non-specific Low Back Pain (NSLBP). Methods Thirty females with NSLBP were randomly assigned to two control (n = 15) and experimental (n = 15) groups. The experimental group received 3 stretch practice sessions per week for a period of 8 weeks. The Oswestry low back pain Disability Questionnaire (ODI), visual analog scale (VAS), and passive hip range of motion (PROM) were employed before and after the intervention. Results The results of mixed model analysis of variance indicate that the group × time interactions was not significant (p > 0.05) for all measurement outcomes. However, there was a main effect for Time (ODI: p = 0.002, VAS: p = 0.001, PROM-R: p = 0.016, PROM-L: p = 0.001). Such that the...

International Journal of Sports Medicine

The purpose of this study was to compare muscle activation during the squat with different hip ro... more The purpose of this study was to compare muscle activation during the squat with different hip rotations (neutral, 15, 30, and 45° of internal and external hip rotation) in subjects with and without Genu Varum deformity deformity. Surface electromyography were recorded from 32 men with (n=16) and without (n=16) Genu Varum deformity. In the Genu Varum deformity group, the squats with 30, 45 and 15° of internal rotations of the hip showed significantly greater gluteus medius activation as compared to other positions. Moreover, the tensor fascia lata activity increased with greater external rotation of the hip, and significantly more than hip internal rotations (p<0.05). For vastus medialis and vastus lateralis, both hip internal and external rotation showed a significantly greater activation compared to the neutral hip positions (p<0.05). There were significant differences in the gluteus medius:tensor fascia lata activity ratio (p=0.001) and the vastus medialis: vastus lateralis...

Journal of Sport Biomechanics

Objective Considering the importance of balance in performing daily tasks and sports activities, ... more Objective Considering the importance of balance in performing daily tasks and sports activities, it is necessary to examine the balance of the body from different angles. The aim of this study was to compare the changes in Center of Pressure (COP) and Time to Stabilization (TTS) in students with and without hyperlordosis. Methods In this study, 30 female students of Tehran's middle school with a range of 14-15 years old who were selected by available sampling method were participated. Subjects' spinal curvature was evaluated by a flexible ruler. Which divided into two groups: 15 patients with hypereloidosis and 15 healthy subjects. To assess postural static stability in a static state, from open and closed eyes on the force plate (Ver 3.0.2 model from an Iranian scientist) was used. also to assess postural stability in the dynamic state, the landing stability test on the force plate device was used. Independent Sample T test statistics were used to analyze the data. Results The results of the statistical test showed that there was no significant difference in the parameters of the center of pressure (COP) in two-position with open and closed eyes between the two groups of healthy and hyperlordosis (P>0.05). But the time to stabilization (TTS) between the two healthy groups and hyperlordosis was statistically significant (P<0.05). Conclusion The results of this study showed that the Spine Curvature Disorders (hyperlordosis) as a risk factor can distort the dynamic balance index (time to stabilization), But has no affect the static balance with both open eyes and closed eyes (center of pressure).

Physical Therapy in Sport