پژوهشنامه فیزیولوژی ورزشی کاربردی
پیاپی 31 (بهار و تابستان 1399)

Obesity is a global epidemic and a risk factor for many diseases. miRNAs are increasing as pathological molecular determinants of pathologic processes. The aim of this study was to investigate the effect of 12 weeks elastic band resistance training on mir-34a expression and cardiovascular risk factors in obese elderly women.

In this single blind randomized clinical trial (RCT), 49 elderly women with obesity (based on the results of the DEXA test, age 64.13 ± 3.68, fat percentage 45.4 ± 6.56, BMI 33. 1 ± 3.71) were divided into two groups: control (n=22) and training (n = 27). The training group performed elastic band resistance training for 12 weeks and three sessions at week for all major muscle groups. 48 hours before and after 12 weeks of intervention, blood sampling was performed.

The results of the intergroup comparisons indicated a significant decrease in mir-34a expression and LDL levels and a significant increase in HDL in the training group compared to the control group (P = 0.05, P = 0.03, P = 0.03, respectively), whereas There was no significant difference in body weight, body mass index, fat percentage, total cholesterol and CRP.

It seems that 12 weeks elastic band resistance training have been able to modulate and reduce the serum concentration of mir-34a in obese elderly women, which was associated with a decrease in LDL levels and increase levels of HDL(p≤0.05), although body mass index, fat percentage, total cholesterol and CRP Significant changes were not observed, which may be due to the type and intensity of the exercises, which requires further investigation in this field.

Optimization of positive effects of exogenous supplements on sports performance is very important. The aim of this study was to investigate the Synergistic effectof L-carnitine and caffeine supplements on physiological variables corresponding to anaerobic threshold (AT) in Kerman karate men.

Fifteen elite karate athletes performed a progressive standard test following placebo (250 mg Lactose), caffeine (5 mg/kg), L-carnitine (3 g), and caffeine and L-carnitine (5 mg/kg, 3 g) consumption in four sessions separated by one-week intervals. Blood sample was collected before supplement consumption and immediately after exercise. Respiratory gases were measured throughout the test. Heart rate and oxygen consumption corresponding to AT were determined, and compared among trials by repeated measures analysis of variance.

End test values of plasma fatty acid (FFA) and its changes during exercise in caffeine and combined trial were significantly higher than those values in the control trial (both p <0.05), but plasma triglyceride levels were not significantly different between trials. The workload and oxygen (O2) corresponding to AT were significantly higher in the caffeine and combined trials compared to the values found in the control trials (all p <0.05). There was no significant difference regarding other variables among trials. Simultaneous consumption of caffeine and L-carnitine improved the values of O2 (11 vs. 17%) and workload (12 vs. 21) corresponding to AT compared to caffeine consumption alone, although there was no significant difference between groups.

Caffeine consumption can improve endurance performance through increasing fatty acid availability and this effect could be exacerbated by simultaneous consumption of L-carnitine.

Blood flow restriction has been suggested as a complementary method to improving physical fitness indicators. However, the efficacy of this method along with interval running training has received less attention. The aim of this study was to examination the effects of eight weeks interval-training with and without blood flow restriction (BFR) at different intensities on endurance performance, strength and serum level of Myostatian in male athletes.

Thirty two young athletes (19.6 ± 0.49 years; 59.3 ± 6.44 kg) were selected and randomly divided into four groups and training based percent of maximal aerobic speed (MAS): 85% MAS with (N=8) and without (N=8) BFR, 100% MAS (N=8) and control (N=8). The participants completed 24 training sessions (3 sessions per week) comprised of repeated bouts of 2 min running on a treadmill interspersed by 1-min recovery. Blood sampling and tests were taken before and after training period. The one-way repeated-measures ANOVA was used to determine difference between groups. The significance level was set at P ≤ 0.05.

There were significant difference in leg muscle strength, endurance performance and serum level of Myostatin between groups. Leg muscle strength significantly increased only in group 85%+BFR and endurance performance significantly increased in 85% with BFR and 100 groups, so, serum level of Myostatin significantly decreased in 85% with BFR and 100 groups.

The results suggest that low intensity interval running with BFR can improves simultaneously both aerobic fitness and muscle strength in athletes and more benefit have in compare to high intensity interval training.

Exercise along with the desired effect on some physical systems may be associated with the disorder of other systems. Although endurance training is a "golden exercise" for general health, but based on the scientific studies, it can be associated with reproductive system disorders; the purpose of the present study was to investigate the effects of endurance swimming on the histomorphometric indices of testis in adult male Wistar rats.

For this purpose, rats (N=10) were randomly divided into control (C) (n=5) and endurance swimming (ES) (n=5) groups. The rats in ES group were exposed to 45 minutes' endurance swimming, three sessions a week for 6 weeks. Forty-five hours after the last swim session, rats were euthanized, research ethics considered. Their testes were placed in 10% buffered formalin solution and sent to the laboratory for histomorphometric evaluations. Data were analysed using independent t-test at α=0.05.

Tubular differentiation indices (TDI) (p=0.001), cumulative coefficient (RI) (p=0.00), spermiogenesis index (SI) (p=0.00) and number of Sertoli cells (p=0.01) of ES group were significantly less than C group, but differences in Leydig cell parameters (p=0.45), testicular capsule thickness (p=0.07), tube diameter Spermatogenesis (p=0.92), sperm tube-forming epithelium height (p=0.117), number of spermatogenic tubes (p=0.51) and inner tube lumen diameter Spermatogenesis (p=0.29) were not significant. The histological profile of the testis of ES group showed severe spermatogenesis.

Endurance swimming protocol of this study can provoke reproductive and infertility disorders, and given the role of endurance activity in public health, especially cardiovascular health, complementary strategies should be considered to prevent the occurrence of such complications.

The aim of present study was to examine the difference between the cardiovascular performance of women and men due to running effects using phase space dynamics.

Fifty four University students were voluntarily participated in this study and divided in two groups’ male (34 participants, 21.68±1.66 years old and 67.01±9.77 Kg) and female (20 participants, 22.4±5.33 years old and 54.1±5.79 Kg). Heart rate variability (HRV) parameters as a function of the cardiovascular system indices measured in these subjects. Using drawing the phase space dynamics and applying the Poincaré section, the features of the time-domain extracted. Data were analyzed by an independent t-test with a significance level (p<0.05).

The results of this study showed that the HRV parameters, i.e., P-Com, PNN50, HRmax, Tr, and  in men’s group significantly altered compared to the women’s group. We found that the average time for reach to maximum heart rate was higher in the women's group and that the average PNN50 and rMSSD parameters in the men's, were higher than the women's, which was stimulated by the parasympathetic and vagus nerve and affected. So this point demonstrated the slowest rhythm of the heartbeat in men.

According to the experimental results, during exercise activities, there is a phenomenon of hysteresis in the cardiac phase space arising from the chaotic and nonlinear dynamics of the biological system in the human body. Therefore, the analysis of these parameters indicates that the intervals between two consecutive beats are higher in men. Thus, they have fewer beats rhythm. Besides, this group is almost more physically fit than women are.

Menopause is a physiologic process and diabetes is a metabolic disease that occurs with high prevalence in old women. In this study effects of exercise training on some biochemical parameters and factors ofTumor necrosis factor alpha (TNF-α) andInterleukin 6(IL-6) investigated in ovariectomized and diabetic rats.

In this empirical study 50 mature female rats divided into five groups that 10 rats attributed to each group and were studied for eight weeks. The first as control group, the second group as ovariectomized (bilateral), third group as diabetic ovariectomized rats, fourth group as ovariectomized under swimming training, and fifth group as diabetic ovariectomized under swimming training rats. At the end experimental period, tissue sampling was performed and changes of biochemical and pre-inflammatory factors were determined.

The blood glucose concentration increased in diabetic and diabetic ovariectomized (p < 0.001). The concentration of malondialdehyde increased in ovariectomized (P=0.025) and diabetic ovariectomized (p < 0.001) groups and decreased with training (P=0.040). The activity of superoxide dismutase (P=0.021), glutathione peroxidase (P <0.001) and catalase (P=0.010) decreased in diabetic ovariectomized group, which increased with training. (P=0.023, P=0.041 and P=0.027, respectively). The pre inflammatory factors (TNF-α and IL-6) were increased in diabetic and diabetic ovariectomized groups (p < 0.001) while training decreased the increased amount of these factors.

The menopause and diabetes lead to increasing of the renal pre inflammatory factors and harmful changing in the antioxidation enzymes. The aerobic training like as swimming can be used as an effective factor in improving these factors.

Proper nutrition, especially essential energy and nutrients intake, is very important, particularly for women athletes. This study was conducted to investigate the nutritional status of Iranian national karate athletes.

This descriptive-analytical study was conducted on 15 Iranian women karate athletes of the national team aged 14-18. The required data were collected using general information questionnaires, and food and 7-day activity diaries were also kept. The data were analyzed using Nutrition 4 and SPSS 22.

The average calorie intake was 2368 ± 540 and the daily energy intake was 2446 ± 354 kcal/day. The average carbohydrate, protein, and fat intake were within the recommended DRI values. Carbohydrates, proteins, and fats accounted for 55.36, 14.52, and 30.11 percent of the total daily energy intake, respectively. Regarding the micronutrients, the average intake of vitamins D, E, pyridoxine, folate, calcium and magnesium was significantly lower and vitamins A, K, C, Thiamine, riboflavin, niacin, pantothenic acid, biotin, cobalamin, Phosphorus, iron, zinc and copper were significantly higher than the recommended DRI values.

in terms of most of micronutrients, the nutritional status of karate athletes was different from standard values. The difference between the nutrient intake and the recommended doses may affect the athletes' physiological growth as well as their athletic function. Therefore, controlling and reviewing the athletes' diet seems essential. As a result, athletes need nutritional information (nutrition before, during, and after exercise) and the knowledge about different food groups.

Due to the protective effects of resistance training and Zataria Multiflora supplementation on hepatocytes, the purpose of this study was to investigate the effect of 8 weeks of resistance training with supplementation of Zataria multiflora on liver enzymes, hepatic steatosis index of men with non-alcoholic fatty liver.

In this semi-experimental study, subjects were randomly assigned into four groups: control, resistance training, supplementation of Zataria multiflora and resistance training with Zataria multiflora supplementation. The training program consist of eight weeks resistance exercise training for, 3 sessions per week, each session with intensity of 80-50% one repetition maximum. For Zataria multiflora supplementation, the Barij capsule was used for 8 weeks, three and half hours before meals. Blood samples were taken to evaluate the status of liver steatosis and liver enzymes (AST, ALT and GGT) before and after the exercise program. For data analysis one-way analysis of variance was used at a significant level of 0.05.

The results showed that resistance training alone and in combination with Zataria multiflora supplementation improve lipid profile (Increased HDL (p<0.001 and p<0.003, respectively), reduction of cholesterol (p<0.02 and p<0.001, respectively), LDL (p<0.003 and p<0.001, respectively) and triglyceride (p<0.002 and p<0.001, respectively)), compared to control group. However, such significant effect was not observed as a result of Zataria multiflora supplementation on the mentioned variables. In addition, eight weeks of resistance training with and without Zataria multiflora supplementation had a significant effect on hepatic steatosis index and hepatic enzyme levels (AST, ALT and GGT) (p<0.05).

According to these findings, it can be concluded that resistance training and not Zataria multiflora supplementation may be a beneficial intervention to improve indicators related to fatty liver (GCT, AST and ALT) in people with non-alcoholic fatty liver. However, understanding its mechanism requires further research.

Cardiac autonomic system dysfunction in type 2 diabetic patients can lead to diabetic neuropathy. The purpose of this study was to investigate the meta-analysis of the effect of aerobic exercise on cardiac autonomic system in middle-aged men with type 2 diabetes.

A total of 256 related articles were selected by searching in the Pubmed, Web of Science, ScienceDirect and Magiran databases. Finally, considering the inclusion criteria, 11 articles were selected for evaluation and analysis after validation using PEDro scale. PICOS method was used to extract data from each article. Then, they were analyzed using Comprehensive Meta Analysis V3.exe software with group comparisons method and random and fixed effects size models of each study.

Regular participation in aerobic training programs in middle-aged men with type 2 diabetes had significant effects on SDNN as time domain index (p = 0.004; effect size = 0.33) and HF as frequency domain index (P = 0.017; effect size = 0.23). Also, these exercises had an insignificant effect on the rMSSD as time domain index (p = 0.096; effect size = 0.50) and LF as frequency domain index (p = 0.184; effect size = 0.47).

Regular participation in moderate intensity aerobic exercise in middle-aged men with type 2 diabetes can partially prevent the effects of this disease on cardiac autonomic system function. Therefore, it is recommended for middle-aged diabetic patients to consider exercise as one of their therapeutic modalities.

Activation of adhesive molecules is an index of endothelial dysfunction and atherosclerosis. The aim of this study was to investigate the effect of eight weeks high intensity interval training (HIT) on levels of ICAM1, VCAM1, E-selectin, P-selectin and L-selectin.

Subjects of this study included healthy young obese women that assigned into control and experimental groups. Subjects of experimental group performed eight weeks HIT trainings (3 sessions per week) with the intensity of 90% heart rate reserve. Blood sampling was done before and 48 hours after trainings. Data were analyzed using Paired T-test and covariance analysis (Ancova).

In experimental group, Weight, BMI and VCAM1 decreased and cardiorespiratory fitness increased significantly (P≤0/05).

Eight weeks HIT training through elevation of cardiorespiratory fitness and reduction of weight, BMI and VCAM1 levels is effective in prevention of risk of atherogenic plaque formation in young obese women. Thus, these persons can use HIT trainings as short duration and time saving trainings for improvement of cardiovascular health.

Recently, the technique of restricting blood flow (BFR) has become more popular among researchers, physicians, physiotherapists, and coaches due to its anabolism effects. Given the importance of adaptive response of hormones and vascular function to exercise with BFR, this study examines the effect of BFR composition and rock climbing activity on the hormonal response of growth hormone and insulin-like growth factor1 and plasma nitric oxide of elite rock climbers.

In this quasi-experimental study with pre-test and post-test design. 20 climbers (weight: 61.55±8.69, fat percentage: 15.29±8.05 and age: 26.6±2.6) as accidentally, they were divided into two training groups (5 men + 5 women each) with limited blood flow and no blood flow restriction. The training protocol was 4 weeks and 3 sessions of climbing training per week. Blood pressure was about 40 to 100 mm Hg. Blood sampling was performed at baseline at rest before and after exercise to determine growth hormone, IGF-I, and nitric oxide levels. Also, the strength of the dominant hand grips was measured before and after the training period. Data were evaluated using spss v16 statistical software and paired t-test and p <0.05.

After climbing training, only a significant increase was observed in the basal level of growth hormone and nitric oxide, but the basal level of IGF-I showed a low increase. And the strength of the dominant hand grips increased in both groups.

Apparently, climbing exercises with blood flow restriction improve anabolic processes, muscle strength, and vascular function.

Progranulin is a novel adipose tissue secreted adipokine correlating with obesity related metabolic diseases such as insulin resistance and type II diabetes. Purpose of this study was to investigate effect of high intensity interval training (HIIT) on serum levels of Progranulin, insulin and fasting glucose and insulin resistance index (HOMA-IR) in young sedentary overweight and obese women.

Twenty overweight and obese women randomly divided into two groups of experimental (mean age 32.5±4.14 years, body mass index 33.18±6.12 Kg/m2) and control (mean age 35.45±2.33 years, body mass index 26.58±1.65 Kg/m2) ones. Subjects in experimental group participated in 8 weeks of HIIT (one minute of running interval at intensity of 90 percent of maximal heart rate and 1 minutes of rest interval of running at intensity of 50-60 percent of maximal heart rate). Blood factors and anthropometric indices were assessed before and after training protocol. Statistical analysis was done by Covariance, t-test and Pearson correlation at significant level of p < 0.05.

HIIT resulted in significant decreases in serum levels of Progranulin (P=.0.013), weight (P=.0.001), body mass index (P=.0.001) and body fat percent (P=.0.001). Moreover, there were significant difference between groups of experimental and control for insulin (P=.0.039), weight (P=.0.001), body mass index (P=.0.005) and body fat percent (P=.0.001).

High intensity interval training (HIIT) resulted in significant decreases in serum levels of Progranulin and can be the effective procedure to improve body composition and metabolic status in young sedentary overweight and obese women.