نشریه فیزیولوژی ورزش و فعالیت بدنی
سال شانزدهم شماره 4 (زمستان 1402)

Obesity, especially central body obesity, is related to cardiovascular diseases risk factors such as high blood pressure and hyperlipidemia. The aim of the present study was to investigate the relationship between blood pressure and serum levels of salusin-β, angiopoietin-like protein 3, lipid profile and anthropometric indicators following eight weeks of interval training with different intensities among women with overweight/obesity.

In this study, 30 inactive women were divided into three groups of 10 including control group (average age, 28.7 years; body mass index, 30.42±3.29 kg/m2), moderate-intensity interval training group (average age, 30.2 years; body mass index, 31.19 ±3.75 kg/m2), and high-intensity interval training group (average age, 28.9 years ؛body mass index, 30.17 ±3.83 kg/m2). The Subjects in training groups performed eight weeks of interval training encompassed pedaling on a stationary bike with different intensities. Blood samples were taken 48 hours before the first training session (baseline values) and 48 hours after the last training session to measure the serum levels of salusin-β, angiopoietin-like protein 3 by using ELISA method. Factorial ANOVA and Pearson's correlation coefficient tests were used to analyze the data.

Data analysis showed a positive and significant relationship (P<0.05) between blood pressure and angiopoietin-like protein 3, waist-hip ratio, salusin-β, waist circumference and an inverse significant relationship between blood pressure and high density lipoproteins (P<0.05).  Factorial analysis of variance showed a significant decrease in the levels of angiopoietin-like protein 3, salusin-β, triglyceride, weight, waist circumference, waist-stature ratio, body mass index, systolic blood pressure and a significant increase in the levels of high-density lipoproteins following eight weeks of interval training (P<0.05). However, no significant changes were observed for low-density lipoproteins, diastolic blood pressure and waist-hip ratio following interval training.

Interval training with sufficient intensity can be effective in increasing obese/overweight individuals’ health by improving body composition and reducing some serum proteins related to high blood pressure.

Steroid receptor RNA activator (SRA) is one of the long non-coding RNA (LncRNA) playing a dual role in glucose homeostasis and insulin resistance. Purpose of this study was to investigate the effect of six weeks of high intensity interval training on adipose tissue levels of SRA and insulin resistance index in diabetic rats with high fat diet and streptozotocin.  

Twenty male wistar rats (10-12 weeks old; 200-300 gr) were selected and type 2 diabetes was induced by six weeks of high-fat diet and streptozotocin injection. Afterwards, obese diabetic rats were randomly divided into experimental and control groups. The rats in the experimental group participated in six weeks of high intensity interval training included 40 seconds of running on a treadmill at 25-35 m/min followed by 2 minutes of active rest at 10 m/min, which was performed for 30 minutes per session, five sessions per week, 6 weeks. All rats were dissected 48 hours after the last training session and adipose levels of SRA, serum levels of insulin and fasting blood sugar were evaluated using appropriate laboratory methods. Data analyses were carried out using independent and paired t-test and Pearson's correlation test at a significance level of less than 0.05.

Six weeks of high intensity interval training resulted in significant decreases in adipose tissue levels of Steroid Receptor RNA Activator (P=0.001) in addition to significant decreases in levels of insulin (P<0.001), fasting blood glucose (P<0.001), insulin resistance index (P<0.001) and body weight (P=0.028) in the experimental group compared to the control group. Furthermore, six weeks of high intensity interval training in experimental group caused significant decreases in body weight in post- test compared to pre- test (P<0.001). However, according to the Pearson’s correlation test, there were no significant correlations between the changes in steroid receptor RNA activator levels of adipose tissue and changes in other variables following high intensity interval training (P>0.05).

It seems that in addition to improving body composition, six weeks of high intensity interval training play a role in improving insulin resistance through decreasing the levels of SRA.

Background and Purpose:

The maximal heart rate is a physiological index to control the intensity of physical activity in exercise and rehabilitation. Due to the practical problems of measuring maximal heart rate in strenuous exercise tests, this physiological index is estimated by regression equations. Most scientific sources have used the two equations of Fox (age - 220) and Tanka (208 -0.7 age) to estimate the maximal heart rate. Fox and Tanaka's equations were designed based on the data obtained from the adult population. Therefore, these two equations may not be highly accurate in the child and adolescent population. The purpose of this research is to evaluate the validity of Fox and Tanaka's equations in estimating the maximal heart rate of children and adolescent boys.

In the present study, maximal heart rate was measured in 349 healthy boys aged 8 to 18 years in a direct method by using modified Bruce test on a treadmill equipped with a respiratory gas analyzer. Thereafter, the maximal heart rate was estimated using Fox and Tanaka’s equations. In order to validate the equations of Fox and Tanaka, the measured and estimated maximal heart rate were compared in all subjects as well as children and adolescent. For this purpose, Pearson's correlation, pair sample t-test, and Bland-Altman's agreements were used.

With increasing the age of the subjects, there was no noticeable change in the maximal heart rate of the boys. So that, a weak negative correlation was observed between age and maximal heart rate (r = -0.198, p<0.05). A significant correlation was observed between the maximal heart rate measured by the standard method with Fox (r=0.198) and Tanaka (r=0.198) equations (P<0.05). However, there was a significant difference between the measured maximal heart rate and estimated maximal heart rate by Fox (mean difference = 5.23±6.32, equivalent to 2.7% of the mean for maximal heart rate) and Tanaka (mean difference = 3.07±6.17, equivalent to -1.44 percent of mean for measured maximal heart rate). The Fox and Tanaka equations led to overestimation and underestimation of maximal heart rate, respectively. Furthermore, the Bland-Altman diagram indicated a low agreement between the maximal heart rate equations of Fox and Tanaka compared to the standard method. Even by dividing the subjects into two age groups, 8 to 13 years and 14 to 18 years, no changes in the results were found. No significant correlation was observed between maximal heart rate of Fox and Tanaka equations with standard method (r = 0.028-0.094) (p<0.05). In addition, a significant (P<0.05) difference was observed between the standard maximal heart rate and the Fox and Tanaka equations (mean difference = - 3.55 to 6.26 beats per minute).

It seems that the Fox and Tanaka heart rate equations do not have sufficient validity in children and adolescent boys. However, in situations where we have to estimate the maximal heart rate, Tanaka's equation has a lower estimation error. According to the results of this research, it will be beneficial to design a native equation for estimating the maximal heart rate of Iranian children and adolescent boys.

Irisin is an exercise-stimulated hormone that affects white adipose tissue and brown adipose tissue. Based on the previous studies, physical activity increases the expression of proteins such as follistatin, which causes weight loss by increasing energy expenditure and through this has an effect on the insulin resistance index. The present study aimed to investigate the response of plasma levels of irisin, follistatin, and insulin resistance index to two types of high-intensity interval training (HIIT) in overweight men.

 For this purpose, 33 overweight men (mean age 22.9±2.11 years, weight 82.45±6.1 kg, body mass index 26.7±1.22 kg/m²) who were able to regularly attend physical activity voluntarily participated in the study and were randomly divided into three groups: 30-s HIIT groups (HIIT-30), 60-s HIIT (HIIT-60), and control. The training protocol was performed three sessions per week for eight weeks. The HIIT-30 exercise program included eight repetitions of 30-second activity at an intensity of 80-90% of the maximum heart rate with a two-minute recovery for the first four weeks, ten repetitions for the fifth and sixth weeks, and twelve repetitions for the seventh and eighth weeks. The HIIT-60 exercise program included four repetitions of 60-second activity at an intensity of 80-90% of the maximum heart rate with a four-minute recovery for the first four weeks, five repetitions for the fifth and sixth weeks, and six repetitions for the seventh and eighth weeks. The control group did not attend any regular exercise program during the research. Blood samples were taken to measure levels of Irisin, follistatin, and determine the insulin resistance index. One-way analysis of variance (ANOVA) and paired t-test were utilized at a level of P≤0.05 to compare means of parameters.

 The within-group comparisons for irisin and follistatin data showed that there is a significant difference between pre-test and post-test in the 30-s HIIT and 60-s HIIT groups (P<0.05). The results of ANOVA indicated that the 30-s HIIT and 60-s HIIT protocols increased the levels of irisin (P<0.05), follistatin (P<0.05), and reduced insulin resistance index significantly (P<0.05). The between-group comparisons of the data showed no significant differences between the HIIT-30 group and the HIIT-60 group for all variables.

 According to the results of this research, it could be concluded that, the two HIIT methods of 30 and 60 seconds by increasing irisin and follistatin levels can cause weight loss, treat obesity and improve the insulin resistance index in overweight men.

Covid-19 is an infectious disease with a very high contagion in the society that its management and control is still considered a challenge for the health systems. Severe respiratory infections with corona various (COVID 19) complications such as hypoxia, lymphopenia, shortness of breath and heart disorders are among the manifestations of this disease. Fatigue, reduced lung function, reduced cardio-respiratory capacity, psychological problems such as depression and stress, reduced quality of life, and movement disorder are some of the permanent post-acute problems of people who have recovered from the corona virus. Due to the novelty of the corona virus, there is not much consistent evidence that rehabilitation training are effective in improving the physical condition, pulmonary and mental function in post-coronavirus patients. Therefore, the purpose of this study was to investigate the efficacy of pulmonary rehabilitation training on pulmonary function, arterial oxygen, stress, depression and quality of life in post-covid patients.

Forty two patients (22 men and 20 women) with moderate to severe consequences of the covid-19 disease in the age range of 45-70 years were admitted to comprehensive 8-week outpatient pulmonary rehabilitation programme and divided into two groups of training and control. The trining protocol included eight weeks of aerobic, mental and breathing exercises (three days a week, 80 minutes per session) under the supervision and monitoring of arterial oxygen EKG. Pulmonary function measurement (PFT), Corona Stress Standard Questionnaire (CSS-18), depression intensity (Beck Depression Questionnaire), and quality of life (SF-36 questionnaire) were assessed befor and after the pulmonary rehabilitation program. Independent t-test was used to compare the data between control and training groups.

The oxygen support in patients with pulmonary rehabilitation was significantly reduced (p<0.001). In addition, the level of oxygen saturation in arterial blood (SaO2%) was significantly improved in the pulmonary rehabilitation group compared to the control both at rest, during exercise and physical activity (p<0.001). The pulmonary function indices (FVC, FEV1), and quality of life significantly (p<0.001) improved in rehabilitation group, whereas the level of stress (p<0.05) and depression (p<0.01) showed significant decreases compared to the control group.

Considering the multifaceted involvement of corona disease and its numerous complications, it seems that compehensive pulmonary rehabilitation training could be effective in post-covid patients through improving the performance, oxygenation of the pulmonary system, and quality of life, as well as reducing the stress and depression which total improve the functional and cognitive abilities.

Diabetes is a metabolic disease associated with increased blood glucose. Based on the results of previous research, physical activity, and herbal supplements containing antioxidants and anti-inflammatory agents play an important role in controlling blood glucose in diabetics. GLUT4 as a glucose transporter and AMPK as an insulin-independent biological pathway play an important role in energy homeostasis in the body. This study aimed to investigate the simultaneous intervention of aerobic training and berberine supplementation on GLUT4 and AMPK gene expression in the quadriceps muscle of diabetic male rats.

In this experimental research, 35 male Wistar rats (age 8 weeks, weight 242.15±10.32 grams) were purchased from the Pasteur Institute of Iran and transferred to the animal house located in the international campus of Yazd University of Medical Sciences. Became Rats were randomly divided into five groups of seven: 1. healthy control, 2. diabetic control, 3. diabetes + berberine, 4. diabetes + aerobic training, 5. diabetes + aerobic training + berberine. Induction of diabetes was done by one-step intraperitoneal injection of STZ (60 mg/kg). Blood glucose above 300 mg/dL meant successful induction of diabetes. The training groups worked on the treadmill according to the protocol for six weeks and with a frequency of five days a week, with a gradual increase in speed and time. Berberine supplementation with a dose of 50 mg per kilogram of body weight was done by gavage on all days and one hour before training. 48 hours after the last training session, rats were deeply anesthetized by intraperitoneal injection of ketamine (75 mg/kg body weight) and xylazine (10 mg/kg body weight) and then Sampling of quadriceps muscle tissue was done. RT-PCR technique was used to investigate the relative expression changes of GLUT4 and AMPK genes. The data were analyzed using SPSS software by one-way analysis of variance and Tukey's post hoc test at a significant level (P<0.05).

AMPK and GLUT4 gene expression in the quadriceps muscle of the diabetic control group was significantly decreased compared to the healthy control group (p=0.0001). Also, the results showed that the content of AMPK and GLUT4 gene expression in (diabetes + aerobic training) and (diabetes + aerobic training + berberine) groups increased significantly compared to the diabetic control group (p=0.0001). This increase in gene expression was higher in the (diabetes + aerobic training + berberine) group than in the (diabetes + aerobic training) group. Also, the level of AMPK and GLUT4 gene expression in the group of (diabetes + aerobic training + berberine) increased significantly compared to the group of (diabetes + berberine) (P<0.005). In the (diabetes + berberine) group compared to the diabetic control group, despite the increase in gene expression of these two variables, it was not statistically significant (P>0.05).

The simultaneous intervention of aerobic training and berberine supplementation has positive synergistic effects on AMPK and GLUT4 gene expression in the quadriceps muscle of type 1 diabetic rats and may improve energy homeostasis in the body.

Physical activity is one of the promising interventions with positive effects on the quality of sleep and cognitive function in multiple sclerosis (MS) patients. With the development of various physical programs, including physical-cognitive combined training,, it seems that these dual interventions may better affect neurodegenerative diseases, such as MS. In the same direction this study aimed to investigate the quality of sleep and psychomotor Vigilance of patients with MS by performing combined aerobic-cognitive training (Brythonic) and conventional aerobic training (Aerotonic).

30 patients (22 women and 8 men) with Relapsing-Remitting and Expanded Disability Status Scale (EDSS) less than four, an average age of 36.66±9.36 years, average height of 164.5±6.30 cm, average weight of 65.43 ± 9.80 kg and average body mass index 24.02 ± 3.02 kg/m2 were randomly divided into 3 groups of 10 people: Brythonic training, Aerotonic training, and control without training. Two groups, Brythonic and Aerotonic, during 10 weeks (20 sessions), two sessions per week, performed relevant online training at home, including 10 minutes of warm-up, 15 to 35 minutes of physical activities, and five minutes of cool-down. In the pre-test and also after 10 weeks of online practice at home (post-test), psychomotor vigilance test (PVT), and Pittsburgh Sleep Quality Index (PSQI), volunteer patients were measured. All the procedure was conducted under the supervision of neurologist with precision. Descriptive statistics (mean ± standard deviation) were used to analyze the data. To investigate the difference between the three groups and the intra-group differences before and after the training period, the repeated analysis of variance test with between-group factor was used and the significance level was considered P≥0.05.

Despite observing a relative improvement in most variables of the PVT test in the Brythonic group compared to the Aerotonic and control groups, these changes were not significant. Also, in the PSQI test, even though a 1-point improvement was observed in the sleep quality of patients in the Brythonic and Aerotonic groups, the changes were not significant.

This study showed that although the repetition of motivational words with aerobic movements in a short training period does not have a significant effect on the quality of sleep and the levels of psychomotor vigilance of patients with MS, due to the improving trend in the Brythonic training group, it is probably suggesting that significant changes in these variables may require more duration or intensity of exercise or cognitive interventions..

Parkinson’s disease is a progressive neurological disorder where loss of dopamine neurons in the substantia nigra and dopamine depletion in the striatum cause characteristic motor and nonmotor symptoms. Glial cell line-derived neurotrophic factor (GDNF) is one of the most important neurotrophins that regenerates dopaminergic neurons by receptor tyrosine kinase Ret in Parkinson's disease. The effect of exercise on these proteins are not well known. The present study was conducted to examine the effect of high intensity swimming training on GDNF and Ret gene expression in hippocampal tissue in rats with Parkinson's disease.

In this experimental study, twenty-one male Wistar rats (age 8 to 10 weeks and weight 200-250 gr) were obtained from the Animal Breeding Center of Islamic Azad University, Shiraz branch and transferred to the animal laboratory of this university. Parkinson's disease induced in fourteen rats by injection of 1 mg/kg reserpine during 5 days and then these rats were divided into Parkinson's disease group or training group randomly. The rats in the training group swam 20 times of 30 seconds with 30 seconds of rest between each time for 6 weeks. Additionally, seven remaining rats were included in the healthy control group without any intervention. GDNF and Ret gene expressions were measured in hippocampus 48h after the last session of training using Real Time-PCR. Data were analyzed using one-way ANOVA test and Bonferoni post hoc using SPSS-22 at the P < 0.05.

Data indicated that GDNF gene expression was reduced after induction of Parkinson's disease and this gene was lower in Parkinson's disease group compare to the healthy control group (p=0.001). For Ret gene expression also our results indicated that this gene was reduced after induction of Parkinson's disease and this gene was lower in Parkinson's disease group compare to the healthy control group (p=0.03). After 6-week of training, GDNF gene expression increases compare to the Parkinson's disease group (p=0.009). For Ret gene expression also our results indicated that this gene expression increases compare to the Parkinson's disease group (p=0.007 respectively); while on significant differences were observed between training group and healthy group (p=0.6 and p=0.9 respectively).

In summary it seems that high-intensity interval swimming training that used in this study improves dopaminergic neuron survival in Parkinson's disease by increasing GDNF as a neurotrophine factor and subsequent signaling, receptor tyrosine kinase Ret. According to limit of information, future studies are needed specially in human cases.

Physiological angiogenesis and homeostasis of blood vessels is a complex process that is regulated at a high level by the balance between positive proteins such as follistatin-like factor-1 (FSTL-1) and negative proteins such as thrombospondin-1 (TSP-1). While there is considerable evidence about the role of positive factors in angiogenesis, however, the role of negative factors is not well defined. In physiological conditions, such as resistance training as one of the effective training methods to improve cardiovascular function, the role of these factors is not properly known. The aim of this study was to investigate the response of thrombospondin-1 and follistatin-like factor-1 of heart tissue to six weeks of resistance training in obese male rats.

In an experimental study, 20 Wistar male rats were divided into two equal groups of control and experimental based on weight homogenization. The experimental group participated in a six-week training protocol with a frequency of three training sessions per week, and each session included 10 repetitions with a 90-second rest interval, climbing a resistance training ladder at a height of one meter and an 85-degree incline with a weight attached to the base of the tail (according to the maximum weight carrying capacity of each rat). 48 hours after the last training session, TSP-1 and FSTL-1 values in heart tissue were evaluated using ELISA method. In order to examine the changes between groups, independent t-test were used at a significance level of p<0.05.

The findings showed that performing six weeks of resistance training protocol in the experimental group compared to the control group caused a significant increase in FSTL-1 values (p=0.0001) and a non-significant decrease in TSP-1 values (p=0.09).

It was determined based on the results of this study that intervention of exercise for six weeks of resistance exercises can have positive effects on the development of angiogenesis process in heart tissue. Based on the findings of this study, it seems that six weeks of resistance training, despite the significant decrease in TSP-1 as an inhibitory factor in the angiogenesis process and an increase in FSTL-1 values as an angiogenesis stimulating factor, may have positive effect on improving blood supply to the heart muscle in obese subjects. The data of the present study refer to the role of resistance training in facilitating intracellular signaling pathways that modulate some inhibitory factors and stimulatory factors in heart tissue angiogenesis in obese rats.

Playing chess under time pressure is one of the most important challenges faced by chess players during various competitions in the final stages of the game, and it affects the performance of athletes in this field during the competition, hence suggesting the suitable training solutions is considered necessary to improve the performance of athletes in this sport field along with its occurrence mechanisms. Therefore, the aim of the current study was to investigate the effect of chess-based training in time pressure on the electroencephalography and skill indicators in chess players.

In a semi-experimental research among chess players (with15-22 years range) in the international level (ELO) range of 2000-1400 who had the experience of at least 3 years of chess activity, 28 subjects were chosen voluntarily and were placed in two groups: chess-based training under time pressure and the normal chess training group. On the first day of the study, electroencephalography indices of the subjects were recorded at rest and during the game under time pressure. The chess-based training group did 12 weeks of special chess training under time pressure in the form of 5 sessions per week each session for 4 hours. In the sixth and after the twelfth week of the study protocol, the electroencephalography and skill indices of all subjects were recorded to determine the absolute and relative power of theta and, alpha waves and the theta to alpha ratio. The data were analyzed with a 3×2 analysis of variance (ANOVA), bonferroni post hoc and independent t-tests using SPSS22 software at a significance level of P < 0.05.

The results showed that before the start of the research project, there was no difference between the studied groups between the absolute and relative power of theta and, alpha waves and the theta to the recorded alpha ratio (P>0.05). Subsequent six weeks of regular and time-limited exercise, a significant increase was observed in the absolute and relative power index of theta, and alpha waves, and the ratio of theta to alpha waves(P<0.05), but no intra-group and inter-group differences were observed in terms of the aforementioned indicators (P>0.05). However, the increase in theta wave and the alpha to theta ratio in the time-limited training group were significantly more than from the normal training group.

It could be concluded that time-limited chess-based training may cause positive changes in the cerebral cortex by modulating theta wave activity. Therefore, time-limited chess training can be an effective intervention to improve the brain waves and electrical activity of the cerebral cortex and potentially improve the brain performance of chess players.