Showing 251 results for Type of Study: Research
Dr Malihe Aveseh, Dr Maryam Koushkie Jahromi, Dr Javad Nemati, Dr Saeed Esmaeili Mahani,
Volume 21, Issue 25 (9-2023)
Abstract
Lactate has been recently considered as a signaling factor involved in metabolism. The aim of this study was to investigate the role of lactate entrance into the brain on endurance training-induced adaptations in lipid oxidation.
24 male rats (age: 8 weeks, weight: 197 ± 21 g) were divided into control (C), trained (T), and traind+4-CIN (T+4-CIN, which experienced the inhibition of lactate entrance into the brain during exercise). All animals performed a single session of acute endurance exercise following their 12-weeks training protocol. Free fatty acids (FFA) and triglyceride content in plasma and adipose tissue and cAMP and Inositol triphosphate (PI3) content in epididymal fat were measured immediately after acute exercise using ELISA and were compared among the groups by one-way analysis of variance (ANOVA).
Acute exercise significantly increased lactate concentration in cerebrospinal fluid (SCF) in both T and T+4-CIN compared to the C group. Lactate concentration was slightly lower in T + 4-CIN compared to the T. Immediately after acute endurance training, a significant decrease of 61 and 31% in plasma triglyceride levels, a significant decrease of 39 and 26% in adipose tissue triglyceride levels, a significant increase of 125 and 56% in plasma FFA levels, a significant increase of 217 and 125% increase in FFA plasma levels, a significant increase of 87 and 41% in adipose tissue cAMP levels, and a significant increase of 90 and 49% in adipose tissue inositol triphosphate levels was observed in the T and T+4-CIN compared to the control group, respectively (all P < 0.01). Plasma triglyceride and adipose tissue levels in the 4-CIN + training group were significantly higher and plasma and adipose tissue FFA levels were significantly lower (all P < 0.05) than the values found in the T group. In conclusion, the results of the present study showed that lactate can be effective on endurance training-induced adaptations in lipid oxidation due to its action in the brain.
Mr Masoud Sebyani, Dr Hooman Minoonejad, Dr Elham Shirzad, Dr Mohammadhossein Alizadeh,
Volume 21, Issue 25 (9-2023)
Abstract
The Prone Hip Extension test (PHE) is used to evaluate the quality of motor control in the lumbopelvic region. Because of the similarity of this test to the walking and running pattern, it seems that muscle interaction in this test is important in hamstring injury. Therefore, this study aimed to investigate the effect of changing the activation patterns of muscles in prone hip extension on kinematical variables affecting hamstring injury. 28 male soccer players participated in this study. The prone hip extension test was used to evaluate and classify subjects, and based on the activation pattern, they were divided into two groups: normal pattern (N=14) and altered pattern (N=14). We used the Myon electromyography device to evaluate the prone hip extension test muscles activation pattern. Also, the kinematic evaluation of running was done on a treadmill at a speed of 20 km/h. Two-dimensional and three-dimensional video analyses were used to extract kinematic data (pelvic tilt, trunk lateral flexion, and trunk flexion). The range of motion in a running cycle and the amount of each variable at the moment of initial foot contact were used. An Independent t-test was used to analyze the data. The results of this research showed that there is a significant difference in the amount of trunk lateral flexion (p= 0/002), and trunk flexion (p= 0/024) at the moment of the initial foot contact and the range of motion of trunk lateral flexion (p=0/019), and trunk flexion (p=0/035) and pelvic tilt (p=0/008) in a running cycle between the changed pattern group and the normal group. The results of this research showed that changing the pattern of muscle activation in the prone hip extension test can increase the risk of a hamstring injury.
Dr Mostafa Haj Lotfalian, Dr Heydar Sadeghi, Mr Soroosh Bagheri,
Volume 21, Issue 25 (9-2023)
Abstract
The purpose of this study was to examine and compare the difference between inside kick, outside kick, toe foot kick and cheap kick with maximum effort, in some parameters associated with the electromyographic activity of the quadriceps muscle. Eight skilled collegiate soccer players volunteered as subjects in the study. These variables were included the average and maximum activation, activation time (AT), the time which the muscles reached to zenith activity (ZAT) and work (W). In order to calculate electromyography of selected muscles contain, RectusFemuris, VastusMedialis and VastusLateralis, ME6000 apparatus with 1080 Hz sample rate was used. Paired sample t-test was used to analyze data. The results indicate similarity between outside and toe foot kicks in average and maximum activity, activation time and work. thus there was no significant difference in electromyographic activity of the quadriceps muscles between these two kicks. But in many parameters, these two kicks were different with inside and cheap kicks. In a nutshell, according to the results, it can be said, quadriceps muscles during various kicks, adapting different trend of contraction which are dependent on the position of the muscles and limbs interaction during soccer kick. And outside kick could be created maximum stimulation in quadriceps.
Vahid Fazeli, Pezhman Motamedi, Hamid Rajabi, Neda Khaledi,
Volume 21, Issue 26 (12-2023)
Abstract
Objective: The aim of the present study was to investigate the effect of combined exercise on aortic atherosclerosis and FGF23 in male rats with chronic renal failure. Methods: In this study, 20 male Wistar rats (mean weight 10 ± 250 g) were induced by NX5 / 6 method for chronic renal failure. After 2 weeks of recovery, they were randomly divided into two groups of control (n= 10) and combined training (n= 10) and performed a combined training protocol for 8 weeks. The combined training protocol consisted of two resistance training exercises on a ladder with 2 sets and 6 repetitions with percentages of body weight and aerobic exercise included 30 minutes of low-intensity treadmill activity. Results: The results showed that combined exercise reduced aortic atherosclerosis and decreased plaques, and FGF23 decreased significantly (p = 0.001). Parathoromon hormone also significantly decreased (p = 0.041) and calcium and phosphorus significantly decreased (p = 0.004 and p = 0.005, respectively). Conclusion: Overall, the results showed that combined training could decrease FGF23, parathoromon hormone, calcium and phosphor on aortic atherosclerosis and cardiovascular disease indices in chronic renal failure patients.
Zahra Ghahremani, Hassan Daneshmandi, Mehrdad Anbarian,
Volume 21, Issue 26 (12-2023)
Abstract
The purpose of this study was to assess the acute effect of warm-up protocols (general and post-activation potentiation) on vertical jump performance and jump-landing technique in female handball players with trunk dysfunction. Twelve trained female handball players with trunk dysfunction participated voluntarily in this study. Subjects randomly performed three different warm-up protocols on separate days: 1- general warm-up protocol, 2- general warm-up with 2 repetitions of dynamic half-squat at %90 of one repetition maximum, 3- general warm-up with 2 repetitions of static half-squat at %90 of one repetition maximum. In the fifth minutes of recovery period after 3 protocols, subjects performed vertical jump and the Landing Error Scoring System tests, and Landing Error Scoring System scores, valgus and flexion angles, and vertical jump height was assessed. ANOVA with repeated measures was used for statistical data analysis. The jump height increased significantly after performing the second and third protocols related to general warm-up (p=0.039, p=0.047 respectively), but there weren’t a significant difference in Landing Error Scoring System score, valgus and flexion angles for three protocols. It seems that the special warm-up method by post-activation potentiation can improve vertical jump performance without influencing Anterior cruciate ligament injury risk.
Mohsen Soltani, Ali Barzegari, Saeed Naghibi, Mohammad Hassaan Dashty Khavidaki,
Volume 21, Issue 26 (12-2023)
Abstract
This study aimed to investigate the effect of quercetin supplementation and training on myostatin and follistatin levels in the heart tissue of diabetic rats. Methods: For this purpose, 50 10-week-old male Wistar rats with an average weight of 237±33 grams were randomly divided into five groups of 10 including: healthy control, diabetes, diabetes+supplement, diabetes+exercise, and diabetes+supplement+exercise. . The training protocol includes five sessions per week for eight weeks on a treadmill without a special slope. The rodents ran for 60 minutes at a speed of 25 meters per minute in each session.and the supplement groups received 50 mg/kg quercetin daily by gavage. The results showed that the difference in myostatin levels among the groups is significant (P=0.001). There was a significant decrease in myostatin levels between exercise+supplement+diabetes group with diabetes (P=0.002). There was also a significant difference between the supplement+diabetes and exercise+diabetes groups (P=0.009). Also, the results showed that the difference in follistatin levels among the groups is significant (P=0.001). The results showed that follistatin levels in the heart tissue increased significantly between the groups of diabetes, exercise+diabetes, supplement+diabetes and exercise+supplements+diabetes with the control group (respectively: P=0.005; P=0.001; P=0.001; P = 0.001).
It seems that moderate intensity aerobic exercise and quercetin supplementation have a positive and beneficial effect on the levels of myostatin and folstatin.
Mojtaba Salehpour, Ali Sarlak, Hadi Samadi,
Volume 21, Issue 26 (12-2023)
Abstract
Introduction: The increase of iron due to aging affects the process of ferroptosis, and the final product of lipid peroxidation, MDA, is the central regulator of ferroptosis. Therefore, the aim of the research was to determine the effect of eight weeks of endurance training on the expression of GPX4 and MDA in the soleus muscle of aged male rats.
Materials and Methods: This study is of an experimental type. 20 healthy rats were divided into two groups of 10 each: training group and control group. The training was done incrementally for eight weeks. 48 hours after the last training session, the soleus muscle of mice was surgically removed and the amount of variables was measured by gene expression and ELISA methods.
Results: There was no significant difference in the level of GPX4 gene expression in the soleus muscle of exercise group rats compared to control group rats (p=0.4079). But the amount of MDA in the training group was significantly reduced compared to the control group (p=0.0028).
Conclusion: According to the findings of the present research, it seems that the effect of endurance training in this research shows a decrease in ferroptosis. The absence of a significant difference in the level of GPX4 gene expression is a sign that endurance training with this intensity does not affect it.
Elahe Talebi-Garakani, Shokoufeh Kheradmand, Khadijeh Nasiri,
Volume 21, Issue 26 (12-2023)
Abstract
The prevalence of obesity in postmenopausal women is higher compared to men. A decrease in estrogen with menopause leads to dysfunction in mitochondria. The purpose of this study is to investigate the effect of high intensity aerobic training(HIT) on the copy number of mitochondrial genome (mtDNAcn) and mitochondrial transcription factor A(Tfam) in visceral adipose tissue(VAT) in ovariectomized(OVX) rats fed with high-fat diet(HFD). 40 rats (8 weeks, 200±20 gr) were divided into 5 groups:1) normal diet (ND), 2) ND+OVX, 3) HFD, 4) HFD+OVX, and 5) HFD+OVX+HIT. HIT performed aerobic training (80-85% of maximum oxygen consumption) for 8 weeks/5 sessions/42 minutes.48 hours after the last training session, VAT samples were taken to evaluate mtDNAcn and Tfam gene expression by qRT-PCR method. ANOVA and LSD tests were used to compare the differences between groups. OVX and HFD didn’t lead to a significant change in Tfam gene expression, but caused a significant decrease in the mtDNAcn compared to the control group. HIT caused a significant increase in Tfam gene expression compared to the control group and Tfam gene expression and mtDNAcn compared to the HFD+OVX. Hence, HIT improves mitochondrial function through mtDNAcn and Tfam gene expression in VAT in OVX rats fed by HFD.
Javid Shah Hosseini, Arezoo Eskandari, Mohamad Fashi,
Volume 21, Issue 26 (12-2023)
Abstract
Using standard tests to assess maximum strength is very important where resistance training planning is based individually. This study aimed to estimate 1 repetition maximum of active women based on the Rating of Perceived and to provide a special predictive equation. 30 healthy women (20-35 years; BMI: 26.32 ± 3.34 kg/m2) performed one repetition of chest press with eyes close and then chose a number to determine the intensity by Rating of Perceived Exertion scale of 6-20. In order to evaluate the validity of the designed equation, one repetition of the maximum number of subjects was calculated by Brzycki equation, and correlation was determined by Pearson's correlation method. There was a high correlation between the present study equation and the Brzycki method (r=0.89) and also after cross validations (r=0.91). No significant difference was observed between the results of the present equation and the results of Berzyski's equation. It seems that the equation of the present study” 1RM={(20-RPE" /" 40) +1 }× weight/2 " can provide a reliable estimate for 1 repetition maximum of chest press in healthy women.
Elham Shahabpoor, Mohammad Amin Delavari,
Volume 21, Issue 26 (12-2023)
Abstract
Cachexia syndrome and the risk of cardiovascular diseases are highly prevalent in cancer patients.The purpose of the present study was to investigate the effect of endurance training as a therapeutic method on muscle cachexia and cardiovascular consequences caused by breast cancer. After 2 weeks of breast cancer induction, 20 BALB/c mice (age: 6-8 weeks and weight: 17- 18 g) mice performed the maximum aerobic capacity test and were randomly allocated into tumor-control and tumor-exercise groups. The tumor-exercise group performed the endurance Training protocol for 6 weeks, 5 days a week with gradual increase in intensity from 12 to 20 (m.min-1) and duration from 25 to 55 minutes And 24 hours after the last training session, the maximum aerobic capacity test was performed. 48 hours after the last training session, the mice were sacrificed. Heart weight, weight of gastrocnemius and soleus muscle, heart mass index, ratio of weight of soleus muscle to body weight and ratio of weight of gastrocnemius muscle to body weight were measured in tumor-control and tumor-exercise groups. Data were analyzed by independent t-test at the significance level of P≥0.05. The results of the present study showed a significant increase in heart weight (P=0.005), spleen weight (P=0.029), weight of the gastrocnemius muscle (P=0.009) and soleus muscle (P=0.022) in the tumor-exercise group compared to the tumor-control group. Also, significant increase in the heart mass index (P=0.016) and the ratio of the weight of the gastrocnemius muscle to the body weight (P=0.005) and the ratio of the soleus muscle to the body weight (P=0.021) were observed in the tumor-exercise group compared to the tumor-control group. In conclusion,Endurance training seems to be a potential treatment method and strategy to improve the health of the skeletal muscle and cardiovascular system and reduce the process of muscle cachexia caused by breast cancer.
Hamdollah Hadi,
Volume 21, Issue 26 (12-2023)
Abstract
The purpose of this research was to determine the effect of different doses of caffeine chewing gum on stress hormones and shooting performance of military men. The subjects of the present research were 10 commanders of Valiasr Police Training Center in Tabriz with a mean and standard deviation of age of 31.52±2.78 years, weight of 75.32±3.91 kilograms, His height was 176.14 ± 4.84 cm. The levels of cortisol, adrenocorticotropic hormone and oxytocin in the blood as well as shooting performance were measured after consuming different doses of caffeine. In the first phase, the placebo was given 15 minutes before the shooting. In the second, third and fourth stages (the time interval between each stage is 5 days), all the subjects were given caffeine gum with doses of 150, 200 and 300 mg 15 minutes before the shooting. Gum and placebo were given to the participants in a double-blind manner. Descriptive statistics, analysis of variance with repeated measures and Tukey's post hoc test were used to analyze the data(P≤0.05). The results of the present study showed that the consumption of caffeine gum in doses of 200 and 300 grams causes a significant decrease in all three stress hormones and also a significant increase in shooting performance, however, the consumption of a dose of 150 mg of caffeine don’t have an effect on the reduction of stress hormones and Shooting performance. According to these results, shooting athletes can be advised to use caffeine gum with doses of 200 and 300 mg before their training and competitions. However, more studies are needed to comment on the use of different doses of caffeine, especially in the form of chewing gum.
