فهرست مطالب mohammad abdollahpourdarvishani

The aim of this study was to evaluate electromyography frequency spectrum of selected lower limb muscles in males with ACL injury during three different running patterns. Fourteen soccer players with ACL injury and 14 healthy soccer players were volunteered to participate in the study. A wireless electromyography system with 8 pairs of bipolar surface electrodes was used to record the electromyography frequency spectrum during three running patterns. The results showed that the median frequency of tibia anterior muscle in the ACL injury group during propulsion phase in the rear-foot strike running pattern was greater compared to the healthy group (p= 0.024). The median frequency of semitendinosus muscle in the propulsion phase in mid-foot running patterns in the ACL group was higher compared to the healthy group (p=.0.044). Also, the median frequency of semitendinosus muscle in the loading response phase in forefoot running patterns in the ACL group was greater compared to the healthy group (p= 0.028). According to the research results, it can be stated increased agonist and antagonist muscle activity across different running patterns increase the risk of secondary injury in people with ACL injuries.

The link between frequency domain analysis of ground reaction forces and hearing loss and blindness during walking is not well understood. Therefore, the purpose of this study was to investigate the frequency domain analysis of ground reaction forces in deaf and blind people during walking.

This study was quasi-experimental. The volunteer participants in the current study consisted of thirty males who were divided into three equal groups: blind, deaf, and healthy (control) groups. Frequency domain analysis of ground reaction forces in three groups was recorded by a foot scan system (sample rate: 300 Hz). The multivariate ANOVA test was used to compare between groups. The significance level was set at P<0.05 for all analyses.

The results showed that the frequency content with the power of 99.5% in the vertical component of ground reaction forces in both deaf (P=0.020) and blind (P=0.021) groups was reduced vs the control group. Also, frequency content with the power of 99.5% in the mid-foot in the deaf (P=0.020) group was more than the blind group (P=0.036).

The present study showed that the frequency content with the power of 99.5% in the mid-foot in the deaf group was more than the blind group. It can be stated that the frequency domain analysis of ground reaction forces has a clinical value. Therefore, the use of therapeutic interventions to improve the frequency domain analysis of ground reaction forces in deaf and blind people is suggested.

Measurement of foot pressure variables can be used to assess the loads to which the human body is subjected in normal activities, like walking, or in more demanding situations such as sports. The purpose of this study was to compare the foot pressure variables in blind and healthy individuals with open and closed eyes during walking.

The present study was a quasi-experimental and laboratory study with pretest-posttest design. The statistic samples included 13 blind men with the mean age of 29.05±3.28 years and 17 healthy men with the mean age of 24.22±1.31  years  participated in this study and were selected by available sampling method.. A foot scan (RS Scan International, Belgium) set was used for measuring planter pressure during walking. Variables data were recorded at a sampling frequency of 300 Hz. For data analysis, paired t-test was run to compare the means within the group; also, independent t-test run to compare the means between the groups using SPSS ver. 16 statistical software.

The results showed that the peak reaction time of the ground reaction force during the heel contact phase was 45.89% higher than blind people compared to the normal participants (p<0.023). The time to peak of vertical force during mid stance in the blind people was 38.97% more than in normal people with closed eyes (p<0.013). The peak vertical loading rate in the blind people was 41.65% lower than normal participants with closed eyes while walking (p<0/003).

Congenital blind people have less stance time in comparison with the healthy people with closed eyes. Decreased walking stance time seems to be related to improved their other senses that requires further research.

Using textured insoles in Autism Spectrum Disorder (ASD) individuals could be effective during walking. This factor is a major cause to change the frequency spectrum of ground reaction forces during walking. The aim of the present study was to evaluate the effect of texture insoles on the frequency spectrum of ground reaction forces in children with ASD during walking.

A quasi-experimental study was conducted on children with Autism Spectrum Disorder selected via available sampling. A total of 10 girls with ASD participated in the present study with the age range of 7-8 years old. A foot scan system (sampling rate: 300Hz) was used to assess frequency spectrum of ground reaction forces during walking with and without textured insoles and bare foot condition. Repeated measures ANOVA was used for statistical analyses.

The results did not show any significant difference in the frequency spectrum of ground reaction forces in the vertical direction, hallux 1, and toes 2-5 among the three conditions of bare foot, shoe, and LP insole (p>0.05). Also, the number of essential harmonies in the third metatarsal during insole condition was lower than that for bare foot condition by 29.32% (p=0.044, d= 1.13).  In addition, the number of essential harmonies of the fifth metatarsal during insole condition was lower than that of shoe condition by 27.19% (p= 0.031, d=1.33).

The present study showed that the use of textured insole reduced the number of essential harmonics in the fifth metatarsal as compared to shoe walking and, therfore, could be recommended for the blind. However, it did not show any significant effect on most of the frequency spectral variables.  Yet, further study is warranted.

The aim of this study was to evaluate the effects of school sport spaces on electromyography activity of lower limb and erector spinae muscles during running in students.Fifteen students with an age range between 10 to 14 years from schools with suitable sport facilities and fifteen students with the same age range from schools with inappropriate sport spaces. A wireless electromyography system with 8 pairs of bipolar surface electrodes (sample rate: 2000 Hz) was used to record the electromyography activity of back and lower limb muscles during running. The results showed that during the loading response phase, median frequency of the tibialis anterior (p=0.005, d=1.27) and medial gastrocnemius (p=0.021, d=0.93) muscles in the suitable sport facilities group were higher than that the other group by 13.45% and 38.28%, respectively. Also, during the propulsion phase, median frequency of biceps femoris muscle in the suitable sport facilities group was higher than that the other group by 28.88% (p=0.002, d=1.37). In addition, during the loading response phase, amplitude of medial gastrocnemius (p=0.024, d=0.84) and erector spinae (p=0.014, d=0.85) muscles in the suitable sport facilities group were lower than other group by 35.55% and 43.29%, respectively. The results of this study showed that students in schools with suitable sport facilities have better performance of the lower limb and erector spinae muscles while running, which reduces the chance of injury during running.

Efficient walking requires the interaction of the three sensory systems for a good maintenance of the balance. In blind people, lack of visual input can harm for walking mechanics. The aim of this study was to compare plantar pressure variables during walking with and without immediate use of textured insoles in blind subjects.

The design of the present study was self-controlled study. 12 blind men (age: 29.66±4.39 years) volunteered to participate in this study. A foot scan system (sampling rate: 300 Hz) was used for measuring plantar pressure variables during walking with and without textured insoles. Paired sample t-test was used for statistical analysis. Alpha level was set at p< 0.05.

Stance time duration did not show any significant difference between both walking with and without insole conditions (p>0.05). Results demonstrated that the medio-lateral displacement of the center of pressure during walking with insoles was lower than that walking without insoles by 35.51% (p= 0.001). First metatarsal peak plantar pressure and force during walking with insoles decreased by 25.69% (p= 0.020) and 64.30% (p= 0.004), respectively. While, peak plantar pressure in second and third metatarsals during walking with insoles increased by 20.03% (p= 0.041) and 28.9% (p= 0.023), respectively. Also, peak force in second metatarsal during walking with insoles was greater than that during walking without insoles by 19.70% (p= 0.010).

Textured insoles improved medio-lateral postural control during walking. Therefore, it could be recommended for blind individuals. However, further study is warranted.

The frequency domain analysis of ground reaction forces is one of the mechanical parameters that can be distinguished by comparing the differences between healthy and patient groups. The purpose of the current study was to compare the frequency domain analysis of ground reaction forces in deaf and healthy control people during running.

The present study was a quasi-experimental design. A total of 30 male individuals were equally divided into two groups of normal hearing and hearing loss (Deaf group). Peak plantar pressure variables in deaf people and healthy control were recorded using a foot scan system (sample rate: 300 Hz). The multivariate ANOVA test was used to compare the ground reaction force frequency domain data during running in deaf and healthy participants.

The results showed that frequency content with the number of essential harmonies in the Toe area (P= 0.012) and fingers 2 to 5 (P=0.035) in deaf was smaller than that of healthy control group. Also, the frequency content with power of 99.5% in the fourth metatarsal (P=0.038) and fifth metatarsal (P=0.019) in deaf group was greater than that of healthy control ones. Stance time during running was more in deaf group than in healthy control group (P=0.032).

According to the results of the present study, it can be stated that deaf people are likely to be exposed to the damage caused by the ground reaction force frequency domain during running.

The Frequency Domain analysis of Ground reaction forces is one of the mechanical parameters that play a significant role in the vulnerability of people while walking and running. The purpose of the present study was to compare the frequency domain analysis of ground reaction forces in deaf and healthy control people during running.

A quasi-experimental study was carried out on 30 males who were equally divided into a healthy group and a group with hearing loss problems (Deaf group). Peak plantar pressure variables in deaf individuals and healthy controls were recorded using a foot scan system (sample rate: 300 Hz).

The results showed that the frequency content with the number of essential harmonies in the Toe foot (p= 0.012) and foot finger 2 to 5 (p=0/035) in deaf were smaller than those of the healthy controls. Also, the frequency content with power 99.5% in the fourth metatarsal (P=0.038) and fifth metatarsal (P=0.019) in deaf were greater than those of the healthy controls. Moreover, stance time during running in deaf group was more than that of the healthy control group (p=0.032).

Stance time during running in deaf group was more than that of the healthy control group, which has the potential for injury in these people.

The Survey of plantar pressure variables provides better understanding of the potential injury to the plantar area nowadays. The aim of this study was the Comparison of plantar pressure variables during walking in male and female.

The present study included 15 males and 15 female. A foot scan set (sampling rate: 300Hz) was used for measuring plantar pressure variables during walking in male and female. Independent sample t-test was used for statistical analysis.

Results demonstrated that the Medio-lateral (p=0/001) and anterior-posterior (p=0/001) displacement of the center of pressure during walking in male is greater than  female. Also fifth metatarsal peak plantar pressure during walking in male is greater than female (p= 0/004). In addition peak force first (p=0/043), third (p=0/049), fourth (p= 0/012), fifth (p= 0/011) and heel medial (p= 0/049) metatarsals during walking in male greater than that female.

According to the findings of this study, the increase in Center of pressure fluctuations and pressure and forces during walking in men and the relationship between pressure and force pattern with injury, indicates more susceptibility to injury during walking in men.

The purpose of the current study was to investigate the effect of quadriceps muscular fatigue on knee joint kinetics and kinematics in professional soccer players.
In the present semi-experimental study, 20 male soccer players (age: 22.90±2.29 years) volunteered to participate. Isokinetic dynamometer (Gymnex ISO 2) was used to measure biomechanical variables during 60, 180, and 360 degree/s angular velocities, each including three repetitions of different flexion/extension velocities. Shapiro-Wilks goodness-of-fit test was used for normality and paired samples t-Test and Two-Way analysis of Variance were used for data analysis (p<0/05).
The results showed that there was a significant reduction in the peak extensor power in angular velocity of 60 degrees/s after fatigue as compared to before fatigue (p=0.002). Also, there was significant effects of velocity factor on peak extensor torque (P<0.001), peak flexor torque (P<0.001), peak extensor ratio torque (P<0.001), peak flexor ratio torque (P<0.001), peak extensor angle torque (P=0.048), peak extensor power (P=0.001), peak flexor power (P=0.003), peak extensor work (P<0.001), peak flexor work (P<0.001), total extensor work (P<0.001), total flexor work (P<0.001), and ratio Flexor strength to Extensor (P<0.001).
Our results demonstrated that peak extensor power in 60 degrees/s reduced after fatigue. Reduction of peak extensor power could be a possible reason of reduction of performance in the final parts of the competition.

Elastic walking with direct involvement of thoracolumbar fascia can prevent from recurrent low back pain. The aim of the present study was to investigate the effect of six weeks of training of elastic walking on the frequency domain of ground reaction forces during running in 10 areas of foot in patients with low back pain. A total of 28 men with low back pain were randomly divided into experimental (n=16) and control (n=12) groups. The participants in the experimental group were trained with elastic walking for six weeks, three days per week, each time for 45 min. Frequency domains of ground reaction forces during both pre- and post-test were recorded using a foot scan system (sample rate: 300 Hz).    The results showed that in experimental group, the number of essential harmonies in the Toe 2 region during post-test was lower than that in the pre-test (P=0.017). The duration of running stance phase during both pre- and post-test were similar in both experimental and control groups (P>0/05). Findings of the present study demonstrated that the effects of elastic gait training on improvement of ground reaction force frequency content in low back patients may have a clinical value during rehabilitation.

The purpose of this study was to investigate the effect of Kinesio Taping method and corrective exercise on Genu Varum and knee kinematics in adolescent soccer players. The present study was a quasi-experimental study with pretest-posttest design. The sample consisted of 30 soccer players with mean age of 16.66 ± 2.32 years with genu varum. Participants took part in this study voluntarity and were randomly divided into three groups including: corrective exercise, tapping and control groups. Q-angle and knee deformity were measured by caliper and universal goniometer. Gait analysis was measured by two cameras with 50 fps. The distance between internal epicondyl and Q angle was measured before and after 8 weeks of taping. The results showed that in Kinesio Taping group there was significant decrease on distance of internal epicondyl (p=0.001) and a significant increase on Q angle (p<0.001), knee angle in mid stance (p=0.008), heel contact (p<0.001), and toe off (p<0.001). Also, in corrective exercise group there was a significant decrease on distance of internal epicondyl (p<0.001) and a significant increase on Q angle (p=0.003), knee angle in mid stance (p=0.003) and heel contact (p=0.045). The finding suggest that both corrective exercise and kinesio taping will significantly affect effect of distance of internal epicondyl and can increase the Q angle. Therefore, it can be concluded that taping and corrective exercises help increase the Q –angle in players who have Genu Varum.

Osteoarthritis is the most common chronic condition of the joints. Osteoarthritis can affect any joint, but it occurs most often in knees, hips, lower back and neck. The purpose of this experimental pretest-posttest study was to determine the effect of eight weeks' core stability and strength training on knee pain and function in elderly women with osteoarthritis.

Thirty-six elderly women with osteoarthritis (mean age, 64/5 ± 4/50 years and mean weight of 70/71 ± 10/52, mean height 156/34 ± 6/12) were participated and randomly divided into three equal groups (n=12): strength training program, core stabilization training and control groups. Strength training, core stabilization training groups received especial training for eight weeks and control group no received any training. To collect the data, Visual Analogue Scale (VAS), functional questionnaire (WOMAC) body composition and dynamometer were used.  Normality of Data and homogeneity was tested by Shapiro–Wilk test. Descriptive statistics, two way ANOVA, paired sample t test and the bonferroni test were used to analyze the hypotheses. (P ≤ 0.05).

The results showed that, there was significant effect of eight weeks' exercises of core stability on, increase muscle strength (d=0.80, p=0.002) and function (d=0.73, p=0.001) and decrease knee pain (d=0.81, p=0.036). Also, there was significant effect of eight weeks' exercises of strength training on increase function (d=0.90, p=0.001) and muscle strength (d=0.73, p=0.041) and decrease knee pain (d=1.52, p=0.003).   

It seems, core stability and strength training can reduce the pain and help to rehabilitation of elderly women with osteoarthritis.