نشریه فیزیولوژی ورزش و فعالیت بدنی
سال سیزدهم شماره 2 (پاییز و زمستان 1399)

 Since obesity and overweight have dramatically increased in recent years, the purpose of this study was to compare the effects of aerobic exercise training in normobaric hypoxia and normoxia conditions on the resting levels of the VEGF, body composition, and the VO2max among Overweight / Obesity Women.

 Twenty-four overweight women voluntarily agreed to take part in the study following the related announcement. The Mean±SD of their age, height, and weight were, respectively, 28.25 ± 3.7 (years), 161.8 ± 3.01 (cm), and 78.64 ± 7.18 (kg). The normobaric hypoxic training group performed aerobic training in hypoxic tents for six weeks, three sessions per week (with 60% of the maximum heart rate), and the normoxic group (control group) performed aerobic training for the same period of time as the hypoxic group. The training program included a 5-minute warm-up following 20 minutes of exercise at 60% of the maximum heart rate for the first week; every week, five minutes were added to the total exercise time.

 The results of comparing pre- and post-exercise changes in body composition indexes for the normobaric hypoxic and normoxic groups indicated that changes in weight (p=0.165) and BMI (p= 0.191) were not significantly different, but the changes in fat percentage (p=0.022) and waist (p = 0.031) were significantly different between the two groups. The changes in the maximal oxygen consumption (p= 0.008) and the VEGF (p < 0.001) following six weeks of training also differed across groups.

The significanlty larger increase in the resting levels of the VEGF in normobaric hypoxia conditions could indicate the importance of physical activity in such conditions in reducing the risk of cardiovascular diseases and vascular endothelial function among overweight people.

Atrial natriuretic peptide secretion from the heart, and can have different effects on different body organs including the effects of these hormones influence the mechanisms of blood pressure. The purpose of this study is to identify the effects of resistance training with blood flow restriction on atrial natriuretic peptide and subsequent blood pressure.

This quasi-experimental study was Cross-group design with repeated measures with the aim of determining the effect of a session of high and low intensity exercise, with and without the of blood flow restriction, on the serum levels of atrial peptide natriuretic and men's blood pressure. To this end, from the available subjects, 8 trained men with an age range from (2575.1±) and fat percentage of (15.7±4.7) were randomly selected. These people with 48 hours of various protocols included: resistive activity with high intensity (%75 1RM) with and without blood flow restriction and the same activity with low intensity (%75 1RM) and without blood flow restriction. Serum levels of atrial natriuretic peptide were examined using ELISA method. Data were analyzed using repeated measure ANOVA.

Therefore, it seems that the effect of high and low intensity resistance exercise, with or without blood flow restriction through the secretion of peptide natriuretic atrial had no difference with each other.

Therefore, it seems that the effect of high and low intensity resistance exercise, with or without blood flow restriction through the secretion of peptide natriuretic atrial had no difference with each other.

Desirable effects of exercise on cardiovascular health in pediatrics due to different physiology than other ages, has not been well elucidated. The aim of this study was to effect of 12 weeks of moderate-intensity aerobic exercise on cardiac structural and functional parameters in pediatrics.

Twenty healthy pediatrics (without regular training background) with average age of 10-12 years participated in this study. Subjects were randomized to one of two groups: control (n=10) and exercise (n=10). The subjects in the exercise group performed aerobic exercise training up to 55 -70% of heart rate reserve, three sessions per week, 25 to min per session for 12 weeks. The cardiac structural and functional parameters were measured with Echocardiography system at baseline and end of 12 week exercise training. The research data were analyzed using independent t- test and Paired t- test (p < 0.05).

In the exercise group in comparison to the control group and baseline conditions LVEDd, LVmass, LVEDV and VO2peak significantly increased (p < 0.05) and resting heart rate decreased (p < 0.05) after 12 weeks moderate intensity aerobic exercise.

The results of present study demonstrates that after 12 weeks moderate intensity aerobic exercise some of cardiac structural and functional parameters in pediatrics will improve, As these changes can have an effective role in improvement of Pediatrics cardiovascular system.

Today, identifying and designing educational, low-cost and accessible exercise interventions for patients, especially those with Multiple Sclerosis appears to be essential. One potential approach may be to practice through media such asose of this study was to investigate the effect of two months pillates training with and without supervision on women with Multiple Sclerosis.

This study was semi experimental with pre-test and post-test design. Thirty women with multiple sclerosis (age: 43/6 ± 6/24 years, Height: 163/20 ± 5/40cm, weight 60/22 ± 6/52 kg) participated and divided into three groups: control, exercise with deliverd CD, and exercise with coach. SPPB test (balance, walking speed, lower extremity strength) was performed before and after training. The exercises lasted for 8 weeks, 1 hour,3 sessions per week. To analysis of data analysis of covariance (p < 0.05) was used.

Results showed that the SPPB scores of the CD group increased in the post-test compared to the pre-test but did not show a statistically significant difference. (p < 0.05, F (1, 13) = 3.52). However, the effect size was 21persent. That is, two months of selective exercise with a CD at home had a 21% effect on SPPB for women with MS. Also There was a statistically significant increase in SPPB scores in the training group (p = 0.005 and F (1,14) = 0 .11).

It can be concluded that selected Pilate's home exercise with CD on the SPPB of MS patients is 21% effective and can be easily accessed with very low cost and cost. Since this research is the first of its kind in the country, further research is needed.

Adipolin is a novel anti-inflammatory adipokine with insulin-sensitizing effects that ameliorates glucose intolerance and insulin resistance. Since physical activity and exercise are one of the effective and safe therapeutic interventions in improving insulin resistance; this study investigated effect of endurance training of two different intensities on adipolin and furin levels and insulin resistance index (HOMA-IR) in sedentary men.

38 sedentary overweight men (BMI>25 Kg/m2, aged 35-50 years) randomly assigned in to two training groups of low (n=13) and high intensity (n=12) and control (n=13) groups. Subjects in moderate intensity training group run on treadmill at intensity of 50-70 % of maximal heart rate and high intensity training group run at 70-90% of maximal heart rate, 30-45 minutes per session and three sessions per week for 10 weeks. Serum levels of adipolin, furin, insulin and fasting glucose and anthropometric indices measured before and 48 hours after last training session. Statistical analysis was done by one-way ANOVA and p < 0.05 considered significant.

changes in adipolin levels were significantly different between group of moderate intensity training and high intensity training one. Moreover, there were significant differences between two groups of moderate and high intensity training and control group for changes in weight, body mass index, body fat percentage and waist to hip ratio.

it seems that intensity of endurance training in addition to effecting anthropometric indices, is the important factor to determine changes of adipolin levels in sedentary overweight men; however, it seems more studies are necessary to identify the mediated mechanism.

Arterial CO2 pressure (PaCO2) is one of important factors in Chemical mechanism of ventilation (VE) control that its direct or indirect effect on VE or its lack of influence is still under discussion. The purpose of the present study was to investigate the effect of PaCO2 on VE during short-term intermittent activity and during recovery after this activity and to investigate time lag in stimulation of VE by PaCO2.

Ten inactive male subjects performed a short-term intermittent activity (10 sec) with work load of 200 watts that induces condition in which only PaCO2 among all chemical factors is changed. VE and gas exchange data were measured continuously during rest, warming up, activity and recovery periods. PaCO2 was predicted from PETCO2 and tidal volume (VT). Cross correlation was obtained for showing correlation coefficient between VE and predicted PaCO2considering various time lags.

The amount of Predicted PaCO2 was significantly higher than warming up levels from 14 sec to 28 sec during recovery and the amount of VE was significantly higher than warming up levels from 14 sec to 90 sec during recovery (p < 0.05) and the highest correlation coefficient between VE and predicted PaCO2 was obtained in time lag of 7s (r=0.854).

The results of this study indicate that in inactive males PaCO2 stimulate VE during short-term intermittent activity and during recovery after that and there is a time lag of 7 sec in stimulation of VE by PaCO2.

Because of exiting uncertainties in growth and maintenance of muscle mass processes, particular atrophy inducing inactivity, the aim of the present study was to investigate changes in the expression of atrogenic genes in the muscle of the rat in which the hind-limbs were kept under unloaded conditions.

For this purpose, 10 male Wistar rats were assign in two groups of suspension (n=5) and control (n=5) and the suspension group rats were kept for two weeks in this conditions. After 14 days, the soleus muscle was extracted and the expression of TRAf6 and MuRF1 genes was measured by real-time-Pcr method.

The results of this study showed that after 14 days of hind-limb suspension, the relative weight of soleus muscle was significantly decreased (P=0.009). In addition, the expression of TRAF6 gene was significantly increased (P=0.033), but MuRF1 was not statistically significant (P=0.061).

Therefore, according to the results of this study, it can be stated that TRAF6 and its downstream factor, MuRF1, can be involved in the regulation of muscle mass in conditions of reduced muscular activity and mechanical unloading and as candidates for controlling muscle mass in conditions such as athlete's hospitalized after sports injuries or hind-limb unloading after injury to be considered.

Exercise training with blood flow restrictionare associated with immunological changes as well as changes in the indices of inflammation and muscle damage. Therefore, the aim of this study was conducted to identify the effect of 4 weeks rock climbing with and without blood flow restriction on response of the LDH, CK and CRP in elite rock climbers.

12 elite male and 12 female rock climbers with at least 4 years rock climbing experience and age range of 23.54±2.32 to 27.18±3.18 years and a fat percentage of 8.22±1.12 to 14.19±1.18 percent were selected purposefully among elite climbers and randomly assigned to one of two groups The exercises were limited by blood flow and exercise without limitation of blood flow. The exercise protocol was performed for 4 weeks (three sessions per week and each session was 90 minutes, severity of each session was 60 to 80% of climbing grades). Blood samples were taken in two stages (pre and post test) in sitting and resting conditions to determine the amount of lactate dehydrogenase, creatine kinase, blood lactate and C-reactive protein. To analyze the data, an independent test was used to compare the meanings and Kolmogorov-Smirnov test for homogeneity of the two groups at a significant level of α ≤0.05.

The results showed that the index of muscle damage of LDH, CK and inflammatory CRP index did not show a significant difference in response to climbing exercises with and without blood flow restriction between the two groups (P <0.05).

According to the results of this study, rock climbing training with or without blood flow restriction, do not increase inflammatory and muscular damage, and this method of training is likely to be safe for climbers due to the mechanical and metabolic pressure of exercise activity.

The prevalence of obesity as a health problem is known in all over the world, as well as diseases associated with obesity, including insulin resistance, metabolic syndrome, type 2 diabetes, high blood pressure and cardiovascular disease has spread. The purpose of this study was to evaluate the effect of exercise training in hypoxia and normoxia on irisin levels and insulin resistance index in overweight men

fourteen non-athlete men divided in either hypoxic (14% oxygen) (mean age 22 ± 1.63 yr and BMI 28.48 ± 1.28 kg/m2) or normoxic (21% Oxygen) (mean age 22.14 ± 1.34 yr and BMI 27.83 ± 2.42 kg/m2) condition randomly. Subjects do aerobic training for eight weeks (each session was 45 minutes, 3 d•wk−1, with 60% VO2max). Subjects performed an exhaustion test to determine the maximum oxygen consumption before the beginning of the training. Blood samples were collected 24 hours before and after the test. Dependent t-test, independent t-test and Pearson correlation test with significant level (P≤0.05) was used to examine the hypotheses.

The result showed a significant increase in irisin level after eight weeks of aerobic training in both normoxia (8%) and hypoxia (12%) conditions, while the HOMA-IR had a significant reduction (P≤0.05); it has to be mentioned that no significant difference has been observed between groups in both irisin and HOMA-IR changes.

Training in both normoxia and hypoxia conditions, through a favorable impact on irisin levels and insulin resistance and can act as an effective factor to improve the complications in overweight men.

The aim of the present study was to investigate the effects of short-term vitamin D supplementation on the pulmonary function and physical fitness factors in adolescent wrestlers.

36 wrestlers (age: 16.18 ± 0.81 years, height: 171.5 ± 5.7 cm, weight64.2±.36 kg, BMI: 21.6 ± 1.75kg/m2, Ft mass: 8.9±1.82%) participated in this study. The subjects in the experimental group received 2000 IU of vitamin D daily and the control group received the same amount of placebo for 14 days, during which time they also performed wrestling training (5 sessions per week). To investigate the research variables, serum 25(OH)D levels, pulmonary function by spirometry test and physical fitness indices were measured twice, before and after supplementation periods. The data were analyzed using the analysis of covariance.

Results showed that vitamin D levels (23%) and FVC indices (20%), FEV1 (17%), MVV (12%), FEV1 / FVC (11%), FEF25 / 75 (13%) were higher significantly in vitamin D compare with placebo group (P>0.05). But there was no significant difference between PEF, FEF25, FEF75, FEF50 and physical fitness factors (shuttle run, 50m sprint, sit-ups, pull-ups, push-ups and Sargent jump) in the experimental group compared to the placebo group (P>0.05).

The present findings of this study indicated that short-term vitamin D supplementation may improve pulmonary function in adolescent wrestlers by affecting respiratory muscle strength and decreasing airway resistance but did not affect their physical fitness.