Showing 239 results for Type of Study: Research
Mr Amir Reza Sedighi, Dr Mehrdad Anbarian,
Volume 18, Issue 20 (11-2020)
Abstract
The purpose of this study was to determine the immediate effect of three types of shoe insoles, on electromyography activity of selected lower extremity muscles during running on treadmill. The electromyography activity of the rectus femoris, vastus lateralis, vastus medialis, biceps femoris, tibialis anterior and gastrocnemius lateralis muscles of 14 male athletes were recorded in non-insole, wearing soft, semi-rigid and rigid insoles conditions during running on treadmill. Electromyography activity of the rectus femoris muscle in the loading phase was lower in soft insole condition than other conditions. In the pre-swing/early swing phase, there was difference of the rectus femoris muscle activity in the soft/non-insole and soft/semi-rigid conditions. In this phase, the biceps femoris muscle had different activity in the semi-stiff/non-insole and semi-rigid/rigid conditions. In the mid-swing phase, there was a difference in the activity of the rectus femoris and the tibialis anterior muscles in the non-insole/semi-rigid condition, and the gastrocnemius lateralis muscle in the non-insole condition with other conditions. There was difference also for biceps femoris muscle activity in the semi-rigid/non-insole condition in the pre-activation phase. The vastus lateralis and gastrocnemius lateralis muscles activity in the soft insole condition was lower than that of the semi-rigid condition. It seems that the intensity and contraction pattern of the muscles change while using different shoe insoles with different variety of stiffness during running. It could be useful in choosing a shoe insole with a suitable stiffness material level for clinical and training purposes.
Karar Khajeh Nemat, Heydar Sadeghi, Ismaeil Ebrahimi Takamjani, Raghad Memar,
Volume 18, Issue 20 (11-2020)
Abstract
Proprioception is essential for joint function and through which individual can detect body parts movement in space. Aim of present study is to investigate effect of balance training on unstable platform with tilting, translation and combined motion on knee joint position sense in active young males. 39 healthy active male divided in to three training and control (n=9) groups. Training on unstable platform with tilting motion group (n=10), Training on unstable platform with translating motion group (n=10) and combined training group (n=10) performed exercises program for 8 weeks, three times a week. Errors in repositioning of knee joint in 30, 45 and 60⁰ angles (active and passive) was measured by Biodex system 3, before and after training period. Data was analysed by using one-way ANOVA test (P≤0/05). Although after 8 weeks, active and passive errors in repositioning of knee joint in mentioned angles decreased in training groups but this difference was not significant (P≤0/05). Balance training on unstable platform alone cannot have a big effect on knee joint position sense in active young male.
Mr Hamid Mahmodi, Dr Hamid Rajabi, Mr Mohsen Bapiran, Dr Pezhman Motamedi,
Volume 19, Issue 21 (9-2021)
Abstract
The purpose of this study was to compare the effect of plyometric training pre and post maturation period with soccer training on electromyographical index and soccer players performance. 30 students of soccer player's pre maturation period (weight 32.38±6.59 kg, age 10.35±0.59 years, and height 141±0.06cm) and post maturation period (weight 43.79±10.96 kg, age 15.43±0.72 years, and height 156.84±0.09 cm) were selected. Subjects in the experimental group were 15 students before and after maturity period. To evaluate the age of the indices such as height, age, dental and bone age (radiographic method) was used. Then, for homogeneous groups of index of biological age radiography was used by radiologists. Before and after 4 weeks of training,, functional tests of two 20 meter speed, agility, vertical jump and also Amplitude for vastus lateralis muscle Were taken. The result by using Paired t-test showed that in pre maturation group in the vertical jump, agility and 20 meters there was a significant difference (P=0.002,P=0.006,P=0.001) and the other variables there was no significant difference. In variations between the groups, independent t-test showed that only significant differences was found in the test 20 meter speed (P = 0.007) and in the other variables not significantly different. The results showed that plyometric training in the Pre maturation group compared to post maturation group were more effect and these results can help in the design training for premature age groups
Mr Iman Rouzbeh, Dr Amirhossein Barati, Dr Hooman Minoonejad,
Volume 19, Issue 21 (9-2021)
Abstract
As Squat is a popular exercise for support of lower extremity muscles in order to injury prevention this study has been hold to comprise the electromyography of vastus medialis and vastus lateralis muscles in three Squat techniques of man soccer players. 15 soccer players, aged 18-25 years old, who had regular exercise more than two years did open, closed and lung Squats exercise while electromyography of vastus medialis and vastus lateralis muscles were recorded. Data analyzed by using dependent and independent T test and repeated measure ANOVA. There was not significant difference of vastus medialis and vastus lateralis muscles’ electromyography during getting up, going down phases and also for different squat techniques. The vastus lateralis muscle show more activity in all conditions. Though, it is recommended that vastus medialis has bold role for controlling of squat exercise, reduction of Q angle and participants’ knee varus in this study can be the reason of antithesis.
, , Elham Shirzad,
Volume 19, Issue 21 (9-2021)
Abstract
Despite the importance of talent for sports, but it has yet received little attention. The purpose of this study was to present a pattern design for talent identification in karate based on artificial intelligence algorithms. Subjects divided to adolescent elite karate athletes (n = 19) and non-karate athletes adolescent (n=20) by convenience sampling. Besed on previous literature, we selected and measured biomechanical and anthropometric variables. The normal distribution of all data was analyzed using Shapiro-Wilk test. Principal component Analysis (PCA) was performed to reduce the number of variables and identify the most important anthropometric and biomechanical variables. Then, for modeling, the neural network algorithm was used with three input layer (10 neurons), middle (7 neurons) and output (2 neurons). The results showed the most important anthropometric variables of adolescent elite karate athletes were thoracic subcutaneous fat, height, jump, static balance, grip strength, chest circumference, ankle circumference, abdominal subcutaneous fat and apparent length leg respectively. Also, percentage of correct classification and sensitive of data was high and 87% and 85% respectively. According to the results of this study, this method can be used for talent karate athletes along with other methods.
Azadeh Doroodgar, Khalil Khayambashi, Shahram Lenjannejadian, Ghasem Yadegarfar,
Volume 19, Issue 21 (9-2021)
Abstract
Hamstrings (Hams) to Quadriceps (Quadr) strength ratio is known as a risk factor for Anterior Cruciate Ligament (ACL) injury and affects by knee and hip flexion angles. Gluteus Maximus (Gmax) muscle acts as a synergist for Hams in hip extension in a closed kinetic chain. The aim of this study was to investigate the effect of Gmax strengthening exercises on the kinetic and kinematic risk factors of ACL injury when single-leg landing from a jump. 25 volunteer women aged 18-30 years were assigned into control (n =13) and experimental (n =12) groups. Maximum isometric strength of Gmax, hip and knee joint angles and ground reaction force (GRF) was measured at landing, by dynamometer, 2D imaging and foot scan respectively,. After 8 weeks of 3 sessions of Gmax resistance training, Following the significant within-subject difference for GRF (F=5.245, P=0.032) by using Two-way mixed model ANOVA, Pre and post-test Differences were significant with 16.63% decrease (P= 0.038, t=2.354). Differences between pre and post-test peak force, time to peak, mean joint angles, impact and load rate were not significant (α = 0.05). According to a 4.55% and 3.47% increase in Gmax strength and time to peak force, and considering the fact that at the beginning of landing, the mechanical advantage of Hams is lower than that of Gmax, the risk of ACL injury could be reduced by reducing GRF following an increase in the Gmax strength.
Dr Shirin Yazdani, Prof Nader Farahpour,
Volume 19, Issue 21 (9-2021)
Abstract
Background and Objective: although it is documented that the spine and hip alignments alter in scoliosis subjects, but the effect of these changes on the lower extremities’ biomechanics have not been well understood yet. So, the aim of this study was to compare hip, knee and ankle joint’s power generation and absorption during gait in patients with adolescent idiopathic scoliosis (AIS) and healthy controls. Methods: Using motion analysis system with 4 Vicon-460 cameras and two Kistler force plates, the kinematics and kinetics of gait was assessed in twenty girls with AIS and 20 matched healthy controls, then the power of the right and left hip, knee and ankle joints in sagittal plane was calculated. Data was analyzed using ANOVA statistical method with significance level of α<0.05. Results: Results showed that in scoliosis group, the peak power absorption of the right knee was significantly 12.5% smaller than that in control group (p=0.01). But, peak power generation and absorption of the hip and ankle joints in both right and left limbs were not statistically differed between the two groups (p>0.05). Conclusion: scoliosis is associated with the smaller power absorption of the knee joint at convex side. This might be linked with unilateral alterations of the joints' moment, joint forces, and the related muscle activity which might impose asymmetrical force to the hip and cause curve progression.
Dr. Leila Ghazaleh, Mis Fahimeh Bakhshizadeh, Dr. Rana Fayazmilani,
Volume 19, Issue 21 (9-2021)
Abstract
It is necessary to examine the changes of muscle co-contraction in different percent of fatigue-induced force reduction. The present study aims to investigate the effect of fatigue-induced force reduction of knee extension on muscle co-contraction. Ten healthy and active women aged 26.10±2.99 years performed fatigue protocol including 5 seconds of maximal voluntary isometric contraction (MVIC) of the knee extension and a 5-second rest. Muscle co-contraction was calculated for each subject in the repetitions in which the MVIC force was reduced by 10, 20, 30, 40 and 50% as compared to the pre-fatigue MVIC force. Knee extension force and muscle activity measured by Isokinetic and electromyography apparatus, respectively. The difference between co-contraction of vastus lateralis and medialis in different percentages of force reduction was not statistically significant. The co-contraction of rectus femoris and biceps femoris increased by 40 and 50% of force reduction compared to pre-fatigue co-contraction (P<0.01). Co-contraction of biceps femoris and vastus lateralis increased by 20, 30, and 40%, as well as co-contraction of biceps femoris and vastus medialis increased 40% of the force reduction, compared to pre-fatigue co-contraction (P <0.05). The results, overall, showed that the change of co-contraction during fatigue is influenced by the selected muscle and the rate of force reduction. This finding can help researchers decide how neuromuscular fatigue effects on muscle co-contraction
Mr Mohamadreza Hatefi, Dr Ramin Balochi, Dr Farideh Babakhani,
Volume 19, Issue 21 (9-2021)
Abstract
The purpose of this study was to investigate the effect of different hip joint postures on electromyographic activity of selected lower limb muscles during squat's movement. Electromyographic activity of selected lower limb muscles of 15 healthy male students was recorded while performing a squat with neutral, 15°, 30°, 45° external and internal rotation of the hip. Friedman's nonparametric test was used to compare muscle activation at different angles of the hip rotation and the Wilcoxon test was used to determine within-group differences. The results of this study showed no significant difference in the activity of Vastus medialis (p = 0.052), Vastus lateralis (p = 0.102) and tensor fasciae lata (p = 0.193) in squat between different hip joint angles, but Significant differences were observed in gluteus medius muscle activation (p = 0.001) and biceps femoris (p = 0.015) in squat between different hip joint angles. Also, the results of this study showed that gluteus medius to tensor fascia lata activation ratio was significant in squat between different hip joint angles. squat with the external hip angles can be considered as an effective method to increase gluteus medius activation and gluteus medius to the tensor fasciae latae activation ratio. On the other hand, 45 ° external and 30 ° internal hip angles can be considered as an effective method to increase the biceps femoris activation.
Mr Amir Hossein Tavari, Dr Mohammad Hadi Honarvar, Dr Mostafa Hajlotfalian,
Volume 19, Issue 21 (9-2021)
Abstract
In recent years, efforts have been made to use non-invasive methods to achieve these angles. The aim of this study was to investigate the capabilities and reliability of a non-invasive system based on surface data mining using infrared depth cameras. To do this, you must first use a number of mathematical relations to create a cloud of points of the surface and to extract the desired deviations by geometric analysis of the map and surface topography. In this study, after extraction of cloud of points, the gossip method based on the second surface derivative was used to identify anatomical landmarks. Based on this, the body surface area was divided into a number of convexity, convection and parabolic. Then, by mathematical analysis of the surface topography map, the angles of a number of backward anomalies were estimated. To test the repeatability of this method, intra class correlation coefficient and minimum detectable changes were used to evaluate the relative and absolute reliability. The results of this study showed that it is possible to identify landmarks using the second derivative method with appropriate accuracy. The results of the reliability survey also showed acceptable and high values for the studied angles. Thus, it can be said that the use of this method has a good introverted reliability and can be a good alternative to radiography in continuous evaluations.
Golnaz Mousavi, Mehdi Varsei , Abosaeed Rashidi, Reza Ghazisaeidi,
Volume 19, Issue 21 (9-2021)
Abstract
The purpose of this article is to biomechanically simulate athlete's leg and compression garment to measure the pressure on a young athlete's leg in order to apply more optimal and uniform pressure distribution while providing a greater sense of comfort when wearing.
The body condition and body shape of the athlete are measured by anthropometric method. Although Using a CT scan of the athlete's body (athlete's limb) and the mechanical properties of the pressure garment (leggings) that made of elastane spacer fabric was simulated by finite element technique. The results of measuring the real pressure on the young athlete's foot were measured and compared by a kikuhime device. The values of pressure applied by the leg in the real state and simulation indicate a maximum error of 14/44 percent (Cross section below the knee and the point behind the leg), a minimum error of 8 percent (Cross section of the ankle and the front point of the leg). Despite the assumptions and sources of error in this simulation, the results show that measured pressure values in the simulation mode with the real mode with incredible accuracy
Somaieh Mahdaviyan, Farshad Ghazalian, Khosro Ebrahim,
Volume 19, Issue 21 (9-2021)
Abstract
The aim of this study was to investigate the effect of 8-weeks of resistance training and vitamin D supplementation on some indicators of renal function in male rats with renal failure. Methods: In this experimental study, 16 male rats (7-8 weeks and mean weight: 350 to 370 gr) were divided into four groups (n = 4): training, supplement, training and supplement and control group. After induction of kidney damage through NX 5.6 surgical method and two weeks later, resistance training was performed for 8 weeks. Simultaneously, 1000 unit of vitamin D per week intramuscularly was injected. Finally, glomerular purification (using urea and creatinine levels) and serum levels of vitamin D, calcium and phosphorus were measured. Descriptive statistics, one-way ANOVA test and Tukey post hoc test were used to analyze the data. The results showed that glomerular filtration and vitamin D in the training and supplementation groups showed a significant increase compared to the control and training groups (P<0.05). However, Urea and creatinine and serum calcium and phosphorus significantly was decreased (P<0.05). It seems that the simultaneous use of resistance training and vitamin D supplementation can affect glomerular filtration rate.
Marjan Asadi, Heydar Sadeghi,
Volume 19, Issue 21 (9-2021)
Abstract
Knowledge of the relationship between performance and range of motion, helping to design training programs, comply of individual with the needs of children is, therefore, The aim of research the relationship between some of the lower extremity range of motion and biomechanical parameters of the boys was performed. Hundred students in this study were randomly selected. After measuring the range of motion of lower extremity, test speed, power, balance and agility of the subjects were recorded. By descriptive statistics to determine the mean and standard deviation of the method of multiple correlations to assess the relationship between the selected range of motion and biomechanical parameters of subjects were used. Hip flexion by speed, hip abduction and knee flexion by balance and hip flexion, hyper adduction and ankle dorsi flexion significant positive correlation by the agility, the rate of hip and knee flexion by power a significant negative correlation and with other lower extremity range motion parameters showed a significant positive association. According to the research findings, seem to be characteristics of the children lower extremity range of motion and identify performance indicators for various athletic field, can be used.
Reza Sabzevari Rad, Hekmat Ehsan Bakhsh, Ebrahim Fasihi Ramandi,
Volume 19, Issue 22 (12-2021)
Abstract
Adiponectin plays an important role in many metabolic and heart diseases. Regulation of liver enzymes is also essential for the health of the body's organs. Therefore, this study aimed to evaluate the effect of a HIIT training period on adiponectin levels and serum concentrations of liver enzymes in obese and overweight boys. 22 obese and overweight boys were selected and randomly divided into two groups of control and experimental. The experimental group performed eight weeks of HIIT pedaling with 80% HR reserve intensity for 3 days a week. The variables of adiponectin, aspartate aminotransferase (AST), alkaline phosphatase (ALP), alanine aminotransferase (ALT) using kits and laboratory methods as well as aerobic power, body mass index, and fat percentage of tests in the two stages before and after Exercise protocol was also measured and covariance test was used to compare the research variables and Pearson correlation coefficient was used to examine the relationship. The results were analyzed at a significant level (P<0.05) using SPSS software version 24. Performing eight weeks of HIIT exercise using a bicycle resulted in a non-significant reduction in adiponectin (P>0.05), AST(P>0.05) and ALP(P >0.05) enzymes. This exercise also significantly reduced ALT enzyme (P<0.05) and fat percentage (P<0.05) and increased aerobic capacity (P<0.05)
HIIT exercise strengthens aerobic power and reduces the percentage of fat and reduces the liver enzyme ALT in obese boys. Of course, more research is needed to clarify this issue.
Fadideh Alabaf Yousefi, Roghayeh Pouzesh Jadidi, Jabbar Bashiri, , Javad Vakili,
Volume 19, Issue 22 (12-2021)
Abstract
Background and Objective: the aim was to investigate the effects of 12 weeks of High Intensity Interval Training (HIIT) and curcumin supplementation on expression levels of FSTL1 and Smad7 and also Type I, III and IV collagens in rat model with myocardial infraction (MI). Methodology: 48 male rats were randomized into five groups of Reference, HIIT, Curcumin, Concomitant (HIIT+ Curcumin) and Control, following isoproterenol induced myocardial infarction. After Reference group execution in order to conform the MI, curcumin was administrated through oral gavage 15 mg/kg.day. HIIT sessions were conducted for five days per week, each session for 60 minutes, consisted of 10 bouts (each for 4 min) of running repetitions at 85-90% of v VO2 peak separated by 2 min active rest intervals between running periods. Left ventricular FSTL1, Smad7 and also type I, III and IV collagens expression level was detected by western blotting. Results: In all three intervention groups of HIIT, Curcumin and Concomitant, the cardiac weight was significantly higher (p=0.001, p=0.018 and p=0.001 respectively), while type IV collagen expression level was significantly lower (p=0.001 in any circumstances) than Control group. However, only in the Concomitant group, a significantly lower type III collagen (p=0.033) expression level as well as higher FSTL1 (P=0.001) and Smad7 (P=0.008) expressions were recorded, compared to the Control group. Conclusion: A diminished cardiac type IV collagen expression level in accompany with a zero mortality rate in all three interventions could likely imply on the safety of HIIT as well as curcumin supplementation to suppress post infraction myocardial fibrosis. However, only concomitant intervention could decrease infracted left ventricular type III collagen expression level, with an elevated FSTL1 and Smad7 expressions, which outlines their synergistic prescription to achieve better results. However, more researches remains to be done because of the lack of evidence and study limitations.
Leila Nazari, Saba Rahmati,
Volume 19, Issue 22 (12-2021)
Abstract
One of the most important issues in community is health and progress people. Because of durability of a community depends on health each person. In this regard, the present study aims to compare anthropometric, biomechanical and psychological factors between university student and student girls done. Subjects of the study were 86 girls 15-17 years old and 113 university student 18-24 years old, took part randomly in this study. Measure anthropometric, biomechanical characteristic also psychological characteristics including general health (GHQ-28) and personality (NEO-FFI) were measured. The result of independent t-test showed that between percent fat and lean body mass, static balance and muscular endurance and all of the general health factors, there are significant differences between the two groups. In generally the subjects are in the border abdominal obesity and high risks associated health them. Doing prevention programs are essential. One of the most important proceedings for this group doing of physical activity and fitness and have a regular exercise program.
Dr Heydar Sadeghi, Mohsen Ali Darchini, Hossein Nabavi Nik,
Volume 19, Issue 22 (12-2021)
Abstract
Core stability (CS) is a popular term that has evolved into a fundamental concept the much rehabilitation, performance training and preventative programs. The purpose of this study is considering the relationship between CS power and endurance with performance of adolescence athletes. 12 male swimmers participated in the study. McGill Protocol, the core stability power, MBESTT and 30/60 sit-up test were used to measure the CS endurance and power, respectively. Participants' performance was measured as the specific (stroke-index, 100m crawl stroke) and general performance (standing-broad-jump (SBJ), vertical Jump, 9.1 m sprint, shuttle-run, flexibility and seated medicine-ball toss tests). The Pearson correlation coefficient was used to determine the relationship between the CS power and endurance with general and specific athletes' performance. The results showed only significance relationship between trunk flexion with SBJ and seated medicine-ball toss, and flexibility and total CS power score with flexibility. Also, negative significance relationship found between left lateral flexion with shuttle-run test and trunk flexion with stroke-index. The findings of this study showed a weak correlation between CS with specific and general athletes' performance. Based on our findings, there is no necessity for focusing on swimming training programs.
Ms Sepideh Samavati Sharif, Phd Abbas Ferjad Pezeshk, Phd Mohammad Yousefi,
Volume 19, Issue 22 (12-2021)
Abstract
This study aimed to determine the role of strength, expulsive power and range of motion of lower limb muscle on the fencing performance of elite florists. In this study, eight elite fencers’ participated. Kinetic variables measured using force plate and kinematic variable measured using motion analysis system. The squat jump test used to measure the compulsive power of the lower extremity muscles of the fencers. The Drop-jump test used to measure the lower strength of the muscles of the lower extremity muscles. Descriptive statistics (mean and standard deviation) used to describe the data and Pearson correlation coefficient used for determine the relationship between data (P≤0.05). The results of this study showed there is a significant relationship between squat jump power and mechanical energy and drop jump height with lunge speed and also between ankle range of motion with peak force and impulse in the anterior direction (P<0.05). Given the results of this study, coaches should have a special attention on the strength and explosive power of plantar flexor muscles.
Mahboubeh Alemzadeh, Seyed Abdolali Hosseini, Mehrdad Anbarian, Safoura Ghasemi,
Volume 19, Issue 22 (12-2021)
Abstract
Nowadays, light and minimal shoes have been used by athletes in various types of sports activities in order to be in a position close to barefoot position. But its effect on the electrical activity of the shank muscles is not well understood. Therefore, the aim of this study was to investigate the electrical activity of selected shank muscles when using minimalist shoes, normal shoes and barefoot during single-leg landing. For this purpose, 15 healthy boys with a mean age of 23.53± 2.64 years who had no history of any abnormalities participated in this study. Electromyographic variables of tibialis anterior, peroneus longus, peroneus brevis, gastrocnemius medialis, gastrocnemius lateralis and soleus muscles of subjects' superior legs were examined in two phases; pre-activity and eccentric. Analysis of Variance (ANOVA) with repeated measures tests were used for data analysis. The significance level was set at α=0.05. The results showed that in both phases, the activity of selected muscles in the shank of individuals during the one-legged landing movement in the barefoot position was more than the minimalist shoes and when using the minimalist shoes was more than normal shoes (P<0.05); Since minimalist shoes have been shown to have moderate muscle activation patterns, between barefoot and casual shoes, it is recommended to use it to prevent sports injuries and also to strengthen the shank and leg muscles in environments where it is not possible to move barefoot.
, , , ,
Volume 19, Issue 22 (12-2021)
Abstract
Aim: Neuropathy control and management is an objective in therapeutic exercises prescribed for patients with Type 2 diabetic peripheral neuropathy. We examined the effects of 12-week integrated exercises (IE) on glycemic control and peripheral sensation criteria in patients with diabetic neuropathy. Methods: Based on scores of MNSI, we assigned 40 patients into two equal paired random groups (control vs. IE). Pre and post-tests were administered before and after three months of intervention for 3 sessions per week with a time of 60 minutes in the first week and gradually increased with the duration and volume of training to 90 minutes in the final session.
Results: Repeated measures ANOVA showed no significant interaction between FBS of the groups (P = .26), but significant interactions were observed between the levels of 2 hrs pp G , 4 pm G, HbA1c, Diapason, Monofilament, and Thermofeel in favor of the IE group (P <.05). Conclusion: At the beginning of the IE, we used massage and foam roller to release pain, and improve blood circulation as well as sensation in the neuropathic areas. This may have helped the patients perform the aerobic and resistance exercises more easily Therefore, better glycemic control and peripheral sensation was achieved. Verification of the long-term effects of this training strategy requires further study.
