نشریه فیزیولوژی ورزش و فعالیت بدنی
سال سیزدهم شماره 1 (بهار و تابستان 1399)

A novel virus that expanded globally from China known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing Corona Virus Disease 2019 (COVID-19). Based on the pandemic and fast spreading characteristics of corona virus (COVID-19), it causes concerns for elderly individuals and those with chronic diseases. To lower the chances of spreading the coronavirus, and preventing the social and economic burden, most of the credible medical centers and organizations have recommended social distancing and isolations. Disclosure of gyms and sport centers and isolation has resulted in inactivity in different individuals. The corona virus disease has led to challenges for keeping the active lifestyle and it can induce some diseases due to inactivity such as obesity metabolic disorders (e.g., diabetes), cardiovascular diseases, and other diseases that can increase hospital referral. Since this is a novel disease and although the effects of regular exercise on it has not been investigated yet, exercise and active lifestyle through increasing energy expenditure, body metabolism, and improving physical and psychological fitness can result in increasing health, reducing virus infection and in the case of having the corona disease it helps a quicker recovery. Since, corona disease influences on the immune and cardiorespiratory system and the person’s physical fitness can be effective in tolerating the disease side effects, this article expands on the effects of regular exercise on immune system, viral infections (inflammation), cardiorespiratory system and physical fitness and at the end presents exercise guidelines for different populations.

Fish is an anti-inflammatory agent that different studies showed its effectiveness on reducing inflammation and improving performance, but its effect on peripheral fatigue mediators is not well understood. Therefore, present study performed in order to investigate the role of fish oil supplementation on tumor necrosis factor-α (TNF-α), nitric oxide (NO) and reactive oxygen species (ROS). For this purpose, 20 healthy students (age: 26.90±2.64 yrs, weight: 78.33±10.42 kg, height: 175.80±4.89 cm, body fat percent: 18.40±5.46%) were voluntarily participated in this study and assigned into control (corn oil) and experimental (fish oil) groups. Participants consumed fish oil for 4-weeks and their response to Bruce exhausting protocol investigated before and after supplementation. In each testing session, blood samples were taken before, immediately after and after 20-min recovery. In addition, ELISA method was used to analyze blood samples. All statistical analysis performed using SPSS software and level of significant defined as P<0.05. Our results showed significant decrease in baseline values of TNF-α and significant increase in baseline values of NO (P<0.05). In addition, two-way ANOVA results showed significant differences between groups after supplementation in changes of TNF-α after recovery (F=7.38, P=0.015) and changes of NO after exercise (F=5.64, P=0.034) and recovery (F=8.83, P=0.011). However, no changes observed in the case of ROS. These results showed that fish oil supplementation can reduce baseline inflammation and thus, increase baseline NO that can improve anti-oxidant capacity. However, TNF-α response to recovery increased that seems to be highly affected by increase in post-supplementation baseline. In addition, NO responses to exercise decreased that is maybe because of the lower physiological pressure of activity.

Although exercise is one of the Medical aid strategies to reduce arterial stiffness in diabetic patients, but the mechanism remains unclear. The purpose of this study was to determine the effect of aerobic exercise on Klotho-fibroblast growth factor-23 (FGF23) axis and arterial calcification in type 2 diabetic Postmenopausal women.

Twenty-four type-2 diabetic Postmenopausal women who were registered at the diabetes association of Shahrood, randomly assigned into two groups including exercise (n=12, 51±6 yrs, 31.9±5 kg/m2) and control (n=12, 52±5 yrs, 29.23.8 kg/m2). The aerobic training consisted of 45 to 60 minutes running with 45 to 70 percent of heart rate reserve, three sessions per week for 8 weeks. Before and after the experimental period, blood fasting samples were taken and the ELISA method was used to analyzed klotho and FGF23. Arterial stiffness analysis was also performed using VaSera-VS-2000. The data were analyzed using the statistical tests of Paired and Independent t-test (P<0.05).

No significant changes in phosphor, FGF23, phosphor × calcium, diastolic blood pressure and VO2max in this study (P>0.05). But, that calcium levels in exercise group decreased significantly following the experimental period (P<0.05). Moreover, systolic blood pressure, klotho/fgf23 and arterial stiffness significantly decreased and klotho significantly increased in exercise group (P<0.05).

aerobic training can decrease the arterial stiffness by modifying the underlying causes of SBP, klotho and klotho/fgf23 in postmenopausal women with diabetes. However, due to the few studies in this regard, these findings need to be validated in the future studies

systemic strength training, proper rest intervals impact of the increase neuromuscular and hormonal adaptations. In this study the effect of different rest intervals on the development of resistance training with strength, body composition and serum levels of anabolic hormones-young men practice was not done.

In this study, 20 young male athletes were selected randomly strength training two groups (each group 10 persons). Program of strength training include: (5 to 8 sets of 3 to 15 repetitions and time of 60 to 90% of one repetition maximum (which both groups with rest intervals varying between sets that the case was in the group 1: rest intervals between sets in the first 3 weeks with 2 minutes rest started and then 6 weeks Training (especially in terms of a period of time, intensity and rest intervals between sets) for 9 weeks, 3 sessions per week were performed. The Two meetings supplementary training exercise (intensity 60% HR) during the week. Then the subjects before and after the 48 hours of training at 10am sampling, fasting blood was drawn and blood samples using Radioimmunoassay laboratory were analyzed. Results were extracted using t-test and a significance level of P <0.05 was considered.

Statistically significant increase in serum concentrations of testosterone and growth hormone and strength training showed in both groups (P = 0.007) and no significant difference was observed between the groups. The results also showed a significant decrease in body fat percentage and body fat mass index showed (P = 0.004) difference was not significant between the two groups.

do resistance training with proper rest intervals have significant effects on physical indicators is often, and it appears resistance training with short rest intervals will lead to further improvements in participants.

Sodium bicarbonate with buffering effect is one of the additives and effective supplement to reduce fatigue. Therefore, the main objective of the present study is to investigate the acute effect of sodium bicarbonate supplementation on anaerobic performance in elite and non-elite male cyclists.

In a single-blind crossover study 12 semi endurance elite cyclist (with 3 year national and international competitions experience) and 16 non-elite cyclist (no history of official competition) in the range of 17 – 29 years old selected purposefully and were placed in two group. Both group within one week, 60 minute before the test, consumed 100 mg placebo (NaCl) or 300 mg sodium bicarbonate per kg of body weight of dissolved in 200 ml of water. The Wingate anaerobic test, measure participants peak power, average power, power drop and recovery heart rate indexes and the results were analyzed by using analysis variance (2 × 2) (α >0/05) . dependent variables response to sodium bicarbonate supplementation had no significant difference between two groups (α >0/05), However, in both group the acute supplementation of sodium bicarbonate result in a significant increase in peak power (P<0/001) and average power (P=0/001) and result in a significant decrease in power drop (P<0/001) and fifth minute recovery heart rate (P<0/001). 

Discussion and Conclusion

According to improvement of anaerobic capacity of elite and non-elite male cyclists following acute supplementation of sodium bicarbonate, its effectiveness is possible regardless fitness level or muscle buffering capacity.

Individuals ability are different for achieving to success in sports disciplines and most of this differences are related to genetic factors. Finding genetic structures that effect on athletic performance is an important step in developing methods related to talent identification. Judo athletes for being successes in this discipline need to high levels of strength and power. The previous investigations revealed the insulin-like growth factor (IGF2) is associated with body mass index, fat-free mass, hand grip strength and leg strength.

The aim of the present study was to evaluate the possible association between ApaI IGF2 and judo status. The athlete group includes 40 elite judo athletes who had medals in Asian and World championship and control group comprised of 120 health non-athletes men.

DNA was extracted from the peripheral blood using a non-enzymatic method and Genotyping was conducted by PCR method for identifying the IGF2 ApaI polymorphism. The distribution frequency of this polymorphism was determined by chi-square analysis.

There were no significant differences in genotype and allele frequency of the judo athletes compared with control.

The result of the present study revealed IGF2 ApaI polymorphism due to the influence of judo discipline from different factors and no relying completely on a single factor (such as strength or endurance) may have no effect in judo status in elite Iranian judo athletes.

Muscle strength is needed for performing many movements and skills in football like speed decreasing, shooting, dribbling, rotating, and jumping. Several studies shown that lower limb muscle strength can increase the quality of exercise skills. But few studies have compared the strength of players at different levels. Therefore, the present study intends to investigate the strength of the isokinetic and isometric knee muscles of the elite, sub-elite and amateur football players of Iran. For this purpose, the isokinetic strength of the knee muscles in 102 soccer players including 29 players of the national under-23 football team of Iran (elite), 29 players of 1st division of under-23 football team of Iran (sub-elite) and 44 players of 2nd division of under-23 football team of Tehran province (amateur) was measured for angular momentum of 60 and 180 degrees per second by the isokinetic Biodex System 4. The isometric strength of flexor and extensor muscles of knee were measured at an angle of 60 degree. The results of the ANOVA test showed that there is a significant difference in strength of flexor and extensor knee muscles in both momentum angles of 60 and 180 degrees per second and flexor/extensor isokinetic strength ratio at 180 degrees per second speed between elite, sub-elite, amateur. However, there was no significant difference in the ratio of flexor /extensor isokinetic strength ratio at 60 degrees per second. Also, there was a significant difference in isometric strength of the extensor and flexor muscles at knee flexion angle of 60 degrees in the three groups. Considering the results of the present study, it can be concluded that exercises and the competition level affect the isokinetic and isometric strength of the knee muscles of young football players of Iran.

Hydrogen sulfide an important role in the body's physiological functions. The aim of the present study was to survey on the effects of 4-week of the special aerobic training on CBS, SAM and H2S levels in hippocampus of Wistar male rats.

Fourteen male Wistar rats (12 weeks old and weight 195 ± 20 g) were randomly divided into two groups including: control and aerobic training. Training group trained 5 days a week for 4 weeks (15 minutes at 10 m/min). ). CBS and SAM mRNA expression in hippocampus was measured by Real time-PCR techniqiue and the ELISA method was used to measure H2S. For data analysis, MANOVA and Eta and Omega squared tests were used to determine the effect size at 95% confidence level (p<0.05).

Findings revealed that the 4-week of special aerobic training increased significantly the CBS, SAM and H2S levels in hippocampus of training rats compared to the control rats ( ES=68.15; P= 0.002, ES= 84.85; P= 0.001, ES= 77.32; P= 0.001).

According to the results, It seems that the special aerobic training can play an important role in physiological and pathophysiological functions through positive regulation of hydrogen sulfide via CBS and SAM enzymes and as a non-pharmacologically beneficial therapeutic treatment for dementia patients.

Aim myocardial infarction(MI) is destruction and cell Death in part of the myocardial that it Happens During an Ischemia. Evidence suggests that exercise training Increased capillary density in Skeletal and myocardial muscles presumably. But Cell process In response to activity and appropriate Intensity is not clear. Vascular endothelial growth factor(VEGF) and endostatin and also their common receptor(FLT-1) are the most important factors involved in angiogenesis. Methodology in this study we investigated the effect of 6 weeks of high intensity interval training on changes of these factors in 12 male Wistar rats with 10-week old with myocardial infarction in two groups, experimental(60 minutes interval running on treadmill, 4 minutes running with 85-90% of VO2max , and 2 minutes recovery with 50-60% VO2max and four days a week per six weeks) and control(no exercise). Result The results show a positive and significant increase in FLT-1 and VEGF and no significant changes in collagen 18 gene expression during HIIT training. Conclusion Overall its results conforms that HIIT training can effective on angiogenesis factors after MI.

Perpose: Sirtuins-3 (SIRT3) is a mitochondrial deacetylase and through acetylation of Oxoguanine Glycosylase 1(OGG1) protein caused repair mitochondrial DNA damage and prevents cell apoptosis. The purpose of this study was to evaluate the effect of vigorous continuous and interval exercise training along with resveratrol on SIRT3 and OGG1 proteins in the liver tissue of male Wistar rats.

Forty eight male Albino Wistar rats divided into six equal groups including sedentary control, resveratrol, interval exercise, interval exercise + resveratrol, continuous exercise and continuous exercise+ resveratrol. Continuous and interval exercise performed for 6 weeks, six days per week, up to 80% and 95 -100% VO2max respectively on a rat treadmill. Resveratrol users received daily supplements as 50 mg/kg of body weight. After intervention, the animals were anesthetized and their liver samples were taken for analysis.

After 6 weeks of vigorous exercise training and resveratrol consumption, OGG1 level was significantly increased in continuous exercise (p=0.0001) and continuous exercise + resveratrol (p = 0.0001) groups. In addition, the level of liver SIRT3 increased in the resveratrol (p = 0.01), interval exercise (p = 0.04), interval + resveratrol (p = 0.04), continuous exercise (p = 0.001) and continuous exercise + resveratrol (p = 0.001) groups; so that the induced elevation in the dependent variables of continuous + resveratrol group was significantly higher than other groups (p = 0.001).

Compare to the interval exercise, performing of continuous exercise along with resveratrol consumption can induce more improvement in the liver mitochondrial function and biogenesis.