Fakhreddin Izadimanesh; Amir Hossein Haghighi; Seyed Alireza Hosseini Kakhk; Majid Asadi- shekaari; Hamid Marefati
Abstract
Background and Aim: Autophagy is a protected lysosome-dependent cellular degradation process that helps maintain homeostasis and metabolic adaptation of the cell. The aim of the present study was to investigate the effect of moderate intensity continuous training on the expression of C/EBPβ and ...
Read More
Background and Aim: Autophagy is a protected lysosome-dependent cellular degradation process that helps maintain homeostasis and metabolic adaptation of the cell. The aim of the present study was to investigate the effect of moderate intensity continuous training on the expression of C/EBPβ and mTOR genes related to autophagy in the frontal cortex of methamphetamine-dependent rats. Materials and Methods: Thirty two male Wistar rats were randomly divided into four equal groups (n=8) of saline, primary methamphetamine, secondary methamphetamine, and methamphetamine-training. Methamphetamine was injected in the amount of five mg/kg for 21 days. The exhausted endurance test and the average maximum speed of the rats were calculated in order to design the training program as it included 24 minutes of running with an intensity of 60-65% of the maximum speed on the treadmill for eight weeks (five sessions per week). At the end, to evaluate gene expression changes, C/EBPβ-mTOR indices were extracted from the frontal cortex tissue of the rats. The results were extracted using one-way analysis of variance at a significance level of p≤0.05. Results: Methamphetamine injection in the primary and secondary methamphetamine groups indicated a significant increase in C/EBPβ gene expression compared to the saline group (p=0.001 and p=0.005, respectively), but in the group early methamphetamine showed a significant decrease in mTOR gene expression compared to the saline group (p=0.04). Moreover, moderate intensity continuous training in the methamphetamine-exercise group indicated a significant decrease in C/EBPβ gene expression compared to the primary methamphetamine group (p=0.04), but as compared to the primary and secondary methamphetamine groups showed significantly increased mTOR gene expression. Conclusion: Methamphetamine injection could probably increases the expression of C/EBPβ autophagic gene in the frontal cortex of the brain; while continuous exercises with moderate intensity, as a preventive strategy, can moderate and regulate autophagy caused by methamphetamine, through increasing mTOR gene expression in the brain.
Mohammad Malekipooya; Mojtaba Khansooz
Abstract
Background and Aim: Research has shown that inflammation is an important factor in atherosclerosis. New markers of heart diseases such as natriuretic peptide-B (BNP) and osteoprotegerin (OPG) during inflammation from atherosclerotic lesions, monocytes, macrophages and endothelium of heart patients; it ...
Read More
Background and Aim: Research has shown that inflammation is an important factor in atherosclerosis. New markers of heart diseases such as natriuretic peptide-B (BNP) and osteoprotegerin (OPG) during inflammation from atherosclerotic lesions, monocytes, macrophages and endothelium of heart patients; it is secreted and plays an essential role in heart attack patients. The present research has investigated the effect of a session of physical activity and early electrical stimulation on some inflammatory markers of infarcted rats. Materials and Methods: In this controlled experimental study with a control group, 50 rats with an average weight of 210±20 g were randomly divided into five groups including healthy, infarcted, physical activity, electrical stimulation, and physical activity + electrical stimulation. The intervention groups underwent physical activity on a treadmill (with a speed of 10 to 18 m/min for one hour) and electrical stimulation (with a foot shock device for 0.5 mA and 20 minutes) for one session. Then, immediately after the intervention, the serum levels of the variables were checked by ELISA method. Data analysis was done with one-way ANOVA test at p<0.05 significance. Results: Induction of infarction indicated a significant increase in the serum levels of BNP and OPG (p=0.0001 and p=0.001 respectively). Moreover, acute physical activity and its combination with electrical stimulation had no significant effect on BNP values (p=0.39) and OPG serum concentration was not affected by acute physical activity (p=0.42); but OPG levels in electrical stimulation groups showed a significant decrease as compared to acute physical activity (p=0.02). Conclusion: It seems that early electrical stimulation alone and along with acute physical activity, by reducing the concentration of BNP and OPG, has no effect on the recovery process of heart markers and needs more study.
Ehsan Eghbali; Hamid Arazi
Abstract
Background and Aim: Creatine hydrochloride is a new form of creatine, it has higher absorption and solubility and also a greater impact on performance due to the properties of hydrochloride. The purpose of this study was to investigate the effect of creatine hydrochloride supplementation along ...
Read More
Background and Aim: Creatine hydrochloride is a new form of creatine, it has higher absorption and solubility and also a greater impact on performance due to the properties of hydrochloride. The purpose of this study was to investigate the effect of creatine hydrochloride supplementation along with resistance training on testosterone, cortisol, strength, muscle hypertrophy and body composition in young men. Materials and Methods: Twenty qualified young men participated in this research. They were divided into two groups (10 people) including resistance training with creatine hydrochloride (0.03 grams per kilogram of body weight per day, taken 30 minutes before training) and resistance training with placebo (with the same dose and time of use). The creatine hydrochloride consumption and resistance training (three sessions per week, with an intensity of 70-85% of one maximum repetition, three times with 6-12 repetitions) interventions were applied for eight weeks. Before and after the intervention, height, weight, body composition (muscle mass, fat percentage and muscle hypertrophy), muscle strength (in chest press and leg press) and serum levels of testosterone and cortisol were measured based on standard valid methods. For statistical analsysis, the results were extracted with the covariance test at a significance level of p≤0.05. Results: Creatine hydrochloride along with resistance training caused a more significant increase in the ratio of testosterone to cortisol, muscle strength of chest press and leg press; cross-sectional area of arm and thigh muscles; and muscle mass; but it also showed a more significant decrease in the percentage of fat and cortisol of the participants, compared to resistance training with placebo. Conclusion: The results show the efficiency of creatine hydrochloride on some variables as: cortisol, the ratio of testosterone to cortisol, the muscle strength of chest press and leg press, and the cross-sectional area of the arm and thigh muscles, and it seems that this type of creatine, considering its characteristics, does not require a loading period, can have beneficial effects on performance and hormonal profile.
Ramtin Sabet; Mohammad Fashi
Abstract
Background and Aim: During the plateau stage of resistance training, in order to cross this stage, it is necessary to manipulate training variables and apply advanced training techniques. Therefore, the purpose of this study was to investigate the acute effects of sarcoplasmic stimulation and traditional ...
Read More
Background and Aim: During the plateau stage of resistance training, in order to cross this stage, it is necessary to manipulate training variables and apply advanced training techniques. Therefore, the purpose of this study was to investigate the acute effects of sarcoplasmic stimulation and traditional resistance training on muscle thickness, plasma volume, and testosterone to cortisol ratio in bodybuilders during a plateau period. Materials and Methods: A crossover design was conducted with 10 bodybuilding athletes (26.71±4.1 years, 3.5±1.6 years of training experience) participating in two traditional and sarcoplasmic stimulation protocols over an interval of seven days. During the traditional protocol, eight sets were performed at an intensity of 70-80% of one repetition maximum until failure. As the same, for the sarcoplasmic stimulation protocol, six reduction sets were performed (three sets of 70-80%, three sets with a 20% load reduction and one set of isometrics until failure). Buresh formula was used to measure acute muscle thickness of the biceps muscle, Castille’s equation was used to measure changes in plasma volume, and blood samples were taken to determine testosterone and cortisol levels. The difference between the pre-test and post-test values of each variable was determined and the changes were analyzed using the paired t-test at the significance level of p<0.05. Results: The results of the present research showed that the resistance training system with sarcoplasmic stimulation showed significant increase on the acute thickness of the biceps muscle compared to traditional resistance training (p=0.03). However, no significant difference was observed between the two protocols (p<0.05) based on the hormonal response of testosterone and cortisol and changes in plasma volume. Conclusion: In trained individuals, the use of the sarcoplasmic stimulation system appears to be an effective method for passing the plateau stage, despite the lower training volume, it involves more metabolic stress and acute swelling than traditional training.
Adel Donyaei; Mehrnegar Rojhannezhad; Farhad Gholami
Abstract
Background and Aim: Considering the relationship between vascular disorders and low-density lipoprotein cholesterol (LDL), the purpose of this research was to investigate the relationship between the LDL and arterial stiffness indices, including cardiovascular-ankle vascular index (CAVI) and ankle-brachial ...
Read More
Background and Aim: Considering the relationship between vascular disorders and low-density lipoprotein cholesterol (LDL), the purpose of this research was to investigate the relationship between the LDL and arterial stiffness indices, including cardiovascular-ankle vascular index (CAVI) and ankle-brachial index (ABI) in the basic state and also after glucose consumption and physical activity. Materials and Methods: This intervention and trial research was conducted on 82 inactive subjects (40 women and 42 men) in the age group of 20 to 45 years of Shahrood city. After 12 hours of fasting, the subjects’ LDL levels were measured. Then the weight, height, body composition and arterial stiffness (cardiovascular index-ankle index (CAVI) and brachial-ankle index (ABI)) were taken at baseline and response 30 minutes of acute endurance activity with 65% maximum heart rate on the treadmill. After 30 minutes of activity, 75 grams of glucose that dissolved in 225 ml of water was consumed, followed by 60 minutes of inactive rest, and the arterial stiffness was measured at the end. Data analysis was performed using simple linear regression and paired t-tests at a significance level of p≤0.05. Results: The results showed no significant relationship between LDL levels and baseline levels of CAVI index in both male and female groups (p>0.05). But, a significant relationship was observed between baseline LDL levels and CAVI index changes (changes in the second stage of measurement after intervention compared to rest levels) in both male and female groups (p=0.001). Also, changes in ABI index were significantly related to LDL only in the male group (p=0.01). Conclusion: It can be concluded that the baseline LDL level can be a sex-dependent predictor of arterial stiffness response to physical activity and glucose consumption.
Hassan Kosari; Pezhman Motamedi; Hamid Rajabi; Shahriar Gharibzade; Shapour Jaberzadeh
Abstract
Background and Aim: Changes in corticospinal excitability will cause a change in the neural output and finally the maximum force will be changed. Various training and non-training factors affect this neuromuscular response and it seems that the intensity of the intervention is one of the effective factors ...
Read More
Background and Aim: Changes in corticospinal excitability will cause a change in the neural output and finally the maximum force will be changed. Various training and non-training factors affect this neuromuscular response and it seems that the intensity of the intervention is one of the effective factors in this regard. Based on this, the present study sought to investigate the response of corticospinal excitability to different intensities of postactivation potentiation in young trained subjects. Materials and Methods: Eight young men (24.8±2.70 year) performed the research protocol in three separate sessions with preparatory contractions during the handgrip movement with intensities of 20, 50 and 80% root mean square of maximal voluntary contraction. Several times after that, the amount of corticospinal excitability, the electrical activity of the flexor carpi radialis muscle (FCR) and the maximum force in the hangrip were measured with a dynamometer. Then, the results were extracted by using the statistical method of repeated-measures analysis of variance at a significance level of p<0.05. Results: The amplitude of motor evoked potential increased after preparatory contraction with intensity of 20%, but it decreased significantly after intensity of 50% and 80%; so that, there was no significant difference between the intensity of 50% and 80%. On the other hand, the amount of voluntary force measured by the maximum voluntary contraction did not show any significant change as well as the electrical activity immediately and after 5 minutes of preparatory contraction. Conclusion: None of the changes in corticospinal excitability were associated with changes in muscle strength and electrical activity. Therefore, there is a complex interaction between changes in supraspinal excitability following preparatory contractions and their effect on an individual’s ability to improve or maintain force output, and further investigations are needed in this area.
Hasan Naghizadeh; Faeze Heydari; Zahra Rostami
Abstract
Background and Aim: The use of medicinal plants along with exercise especially in obese people has received much attention due to the modulation of inflammatory and oxidative responses. Therefore, the aim of this study was to investigate the effect of eight weeks of high intensity interval training (HIIT) ...
Read More
Background and Aim: The use of medicinal plants along with exercise especially in obese people has received much attention due to the modulation of inflammatory and oxidative responses. Therefore, the aim of this study was to investigate the effect of eight weeks of high intensity interval training (HIIT) and green tea supplement on serum levels of acetylcholinesterase (AChE), amyloid beta-42 (Aβ42) and malondialdehyde (MDA) in untrained obese elderly men. Materials and Methods: Forty eight obese elderly men (age 65.42±3.16 years and body mass index 30.93±1.15 kg/m2) were randomly divided into four groups of 12 people including HIIT, supplement green tea, HIIT+ green tea supplement and control- placebo. HIIT training was carried out for eight weeks and three sessions per week. Green tea supplement in the form of six capsules per day in the amount of 450 mg was received by the target groups. Testing was done 48 hours before and after the last training session. The AChE and AB42 were measured by ELISA and MDA by TBARS method. Results were extracted using by analysis of variance with repeated measurement, analysis of variance two -way and Tukey’s post hoc tests at a significance level of p<0.05. Results: The most significant changes (decrease) in body mass index (p=0.01, 3.50%) and percent body fat (p=0.0001, 11.07%); and a significant increase in maximum oxygen consumption (p=0.02, 9.22%) was observed in the HIIT+ green tea group. The combined effect of HIIT and green tea supplementation showed a significant decrease in AChE (p=0.0001, 19.91%), Aβ42 (p=0.0001, 27.99%), and MDA (p=0.01, 26.09%). Moreover, the HIIT caused significant decrease in AChE (p=0.02, 15.67%), Aβ42 (p=0.01, 16.22%) and MDA (p=0.01, 14.14%); and green tea supplement caused a significant decrease in Aβ42 (p=0.023, 6.19%). Conclusion: The combined intervention of HIIT with green tea supplement compared to the effect of each one alone, causes a further improvement of inflammatory and oxidative indices in obese elderly men.
