نشریه مطالعات کاربردی علوم زیستی در ورزش
پیاپی 17 (بهار 1400)

Considering the importance of prevention of risk factors in heart disease and lack of information about the effect of exercise training on angiopoietin 1 and canstatin expression, therefore the aim of this study was to investigate the effect of four types of exercise training protocols on the angiopoietin-1 and canstatin expression in left ventricle of Wistar rats.

For this purpose, 40 male Wistar rats with age of 8-weeks and an average weight of 237±33 grams were randomly divided into five groups (8 rats in each group), including control, moderate intensity training (MIT), high intensity training (HIT), high intensity interval training (HIIT) and moderate-intensity swimming training groups (MIST). The training programs in experimental groups were performed for 8 weeks and 5 days a week. 48 hours after the last training session, the sampling was taken from cardiac tissue. Then, the angiopoietin-1 and canstatin expression were determined by PCR method. To analyze data, one way ANOVA and tukeywere used at a significance level of p≤0.05.

Angiopoietin-1 and canstatin expressions in each intervention groups were significantly decreased compared to the control group (p=0.001). The comparison of four types of training showed that angiopoietin-1 expression was significantly decreased only in MIST group as compared to the other training groups and canstatin expression was significantly decreased in HIT, MIT and MIST groups when compared to the HIIT group (p=0.001).

All of the four types of exercise training methods were able to reduce the expression of the studied genes,and make favorable changes in reducing the consequences of cardiac tissue injury. However, moderate-intensity swimming training seem to have more favorable effects with regard to non-weight bearing property, although further research is needed.

Estrogen reduction during menopause can lead to an increase in oxidative stress and decrease in antioxidant enzymes, but physical activity and nutrition can be considered as two important factors for improving these conditions. The purpose of the current study was to investigate the effect of endurance training and crocin consumption on serum levels of catalase and glutathione peroxidase enzymes medulla in ovariectomized rats.

Thirty six female ovariectomized rats  with average ages ranging from 8 to 10 weeks were divided into 4 groups (n=9) including control, endurance training, crocin consumption and endurance training and crocin consumption groups. During 8 weeks period, the groups endurance training and endurance training plus crocin consumption were subjected to 5 training sessions per week while the crocin consumption and endurance training plus crocin consumption groups were received 25 mg/kg body weight crocin peritoneally. Enzyme levels were measured by the wavelength method and to analyze data one-way analysis of variance (ANOVA) along with Tukey’s post hoc test were used at the significant level of p < 0.05.

Endurance training (p < 0.03 and p < 0.001, respectively), crocin consumption (p < 0.001 and p < 0.001, respectively), and endurance training plus crocin consumption (p < 0.001 and p < 0.001, respectively) had a significant increase on the serum catalase and glutathione peroxidase activity in ovariectomized rats. However, endurance training plus crocin consumption had a greater effect on increasing enzyme levels (p < 0.001).

Endurance training along with crocin consumption can have a protective effect against oxidative stress by increasing serum levels of catalase and glutathione peroxidase medulla in ovariectomized rats.

The effect of resistance training and cold water immersion on muscle injury and inflammation is not clear. The aim of this study was to study the effect of 8-weeks resistance training and cold water immersion on muscle injury and inflammation responses following an acute strength activity in futsal players men.

Twenty futsal players (age 26±3.07 years and body mass index 24±3.40 kg/m2) volunteered to participate in the study and were randomly assigned to experimental and control groups. After first blood sampling, both groups performed one session of acute circular resistance training with 75% of 1-RM at 5 stations, 3 sets, 8-10 repetitions, and a 90-second rest between sets and a 5-minute rest between stations. The second blood sampling was performed after 48 hours. The experimental group performed 8 weeks of circular resistance training, 3 sessions per week like the acute resistance training and immediately after exercise were immersed, 20 minutes at 5-10°C in cold water. Forty eight hours after last training session, blood sampling was performed. Then, both experimental and control groups performed the second acute circular resistance training and one hour later, the fourth blood sampling was performed. The differences of variables at different time intervals were compared with 2×4 two-way ANOVA and Independent samples t-test at p < 0.05. Cearitine kinase (CK) was measured with Iran Alpha Classic Autoanalyzer and Bionic kit; while white blood cells (WBC) count and their subclasses were measured with BC-3000 hematologic auto analyzer and China Mindry kit. The differences between the variables at different times were analyzed by 4* 2 two-way ANOVA and the differences between the two groups were determined by independent t-test at p < 0.05.

CK (p=0.001), WBC and neutrophils (p=0.001) significantly were increased in both groups after the first acute resistance training. After 8 weeks of resistance training-cold water immersion CK (p=0.004), WBC, neutrophils, monocytes, and lymphocytes (p=0.001) significantly decreased in experimental group as compared to the control group. 8 weeks resistance training-cold water immersion significantly decreased CK, WBC, neutrophils (p=0.001), and lymphocytes (p=0.004) in experimental group following the second acute resistance training compared to the control group. Whereas, there was no significant differences in monocytes (p < 0.05).

Resistance training along with cold water immersion could reduce muscle damage and inflammation following acute exercise.

Warm-up is one of the factors that influence the success and improvement of athletes record. The post-activation potentiation can be considered as one of the new methods of warm-up. During fast and dynamic activities, there is a high level of neuromuscular activation, so the exercises with maximum loads can activate the central nervous system tocreate suitable condition for explosive activity. The purpose of this study was to investigate the effect of post-activation potentiation in different rest periods on the explosive power of athlete girls.

In this semi-experimental study, 12 female athletes (mean body mass index 21.1 ± 4.40 kg/m2, and age 23.28 ± 1.98 years) performed a countermovement Jump test using force plate. Then, they performed the squat movement with three repetitions, with 85% of one maximum repetition, and after 30 seconds of passive rest, they repeat the same countermovement Jump test. After that, the same test was carried out with one, two, three, and five minutes passive rest. For statistical analysis, theShapiro-Wilk normality test and analysis of variance with repeated measure method and Bonferron's post hoc test were used. All statistical analyzes were performed by SPSS softwareand significant level set at p < 0.05.

The results indicated that the reverse countermovement  Jump in post-tests were significantly higher at 30 second (p=0.001), 1 minute (p=0.001), 2 minutes (p=0.001) and 3 minutes (p=0.001) compared to pre-test, butdespite a slight increase in countermovement Jump with 5 minutes rest, this test did not change significantly (p=0.43) compared to the pre-test.

It seems that the use of squat movement after warm-up will increase the explosive performance, which can be beneficial in power, speed and explosive power sports.

Peroxisome proliferator-activated receptors beta and gamma (PPARβ and PPARγ) are stimulator of genes expression involved in reverse cholesterol transport and anti-oxidant defense, thus gene expression and activity of this substance can be one of beneficial mechanisms in prevention of atherosclerosis. The aim of this study was to investigate the effect of high intensity interval training (HIIT) and low intensity continuous training (LICT) after high fat diet (HFD) on PPARβ and PPARγ genes expression in male Wistar rats.

This experimental study involved two phases of fattening (13 weeks) and training (12 weeks, 5 sessions per week). After fattening phase, subjects assigned into three groups as: control, HIIT and LICT. Analysis of PPARβ and PPARγ genes expression was done using polymerase chain reaction technique after trainings. Results were obtained using Kruskal–Wallis and Mann–Whitney U tests in level of P≤0.05.

The PPARβ and PPAR γ genes expression were different between control group with HIIT (P=0.008) and LICT (P=0.008) and between HIIT with LICT (P=0.008); so that higher levels of PPARβ and PPAR γ genes expression observed in HIIT group and lower levels were in control group.

Results of this study showed that regular HIIT and LICT through elevation of PPARβ and PPARγ genes expression may be effective in reduction of heart attack risk and HIIT are more effective than LICT.

Skeletal muscles as an Irisin producing site can affect fat metabolism and energy expenditure. The purpose of the present study was to investigate the effect of resistance training intensity on serum levels of Irisin and lipid profile in sedentary elderly women.

Twenty eight sedentary elderly women in the current study were randomly divided into three groups as control, high (80% one-repetition maximum) and low (40% one-repetition maximum) intensity resistance training groups. Resistance trainings were performed 3 sessions per week for 8 weeks. Blood samples were taken before and after the study following 12 hour fasting to measure serum levels of Irisin and lipid profile. Dependent variables were measured by sandwich ELISA and photometric methods. Data were analyzed using analysis of covariance at the significant level of p < 0.05.

The results showed significantly increase on serum Irisin in both high (p=0.02) and low-intensity (p=0.02) resistance training groups than control group. In addition, body fat percent (p=0.002 & p=0.001 respectively) and serum total cholesterol (p=0.01 & p=0.03 respectively) were significantly reduced after high or low-intensity resistance trainings than control group.

Totally, the performing of low- and high-intensity resistance trainings can suggested for older women because of their positive effects on improving Irisin, body fat percent and lipid profile.