فصلنامه علوم زیستی ورزشی
پیاپی 47 (زمستان 1399)

The purpose of this study was to investigate the effects of six weeks endurance training and treatment of stanozolol on hepatic enzymes (ALT, AST and ALP) in male healthy rats. For this reason, 32 male Wistar rats aged 12 weeks old (initial body weight, 289±16g) were divided randomly into four groups; placebo (P, n=8), exercise (E, n=8), exercise stanozolol (ES, n=8) and stanozolol (S, n=8). ES and S groups received a weekly intramuscular injection (5mg/kg of body weight) of stanozolol, while P and E groups received Arashiz oil as placebo. E and ES groups were submitted to a progressive running program on a treadmill, for 6 weeks and 5 days per week. ALT, AST and ALP serum levels were measured by ELISA method. Data were analysed by one way ANOVA test, (p < 0.05). ALT (P=0.002) and AST (P=0.001) changes were significant but ALP changes were not significant. According to the findings of this study, endurance training could not modulate possible side effects of stanozolol on liver tissue.

The aim of this study was to investigate the changes in creatine kinase lactate dehydrogenase, aspartate aminotransferase, and alanine aminotransferase enzymes about recovery with two types of rolling foam after a training session and a disinfectant in futsal men. The subjects of this study, 24 futsal players of Isfahan Province League with an average age of 26.08 ± 2.34 years and a height of 179.03 ± 3.58 cm, were randomly divided into three homogeneous groups (soft foam, hard foam, control). Initially, the subjects performed exhausting exercise, Then the soft foam and hard foam groups did the recovery protocol. And the control group rested. The enzymes were measured in four steps (baseline, immediately after exercise, immediately after recovery, and 24 hours after exercise). Although the activity of all the enzymes in the present study decreased significantly after recovery in both soft foam and hard foam groups, no significant difference was observed between these two groups in the changes of these indicators (p> 0.05). but, all changes in enzymes except lactate dehydrogenase within 24 hours after exercise were significant for both soft foam and hard foam compared to the control group (p≤0 / 0001). As a result, according to the findings of the present study, the physiological effect of these two types of rolling foam is very close. Also, the use of active recovery method using rolling foam compared to inactive recovery has reduced the indicators of muscle damage more and more. And it will get athletes back to basics faster.

The purpose of this study is evaluation of the acute effects of high and low dosages of β-alanine on functional measures during 1km cycling time trial on female athletes. For this purpose, 30 female athletes from Shiraz participated in this study. They were randomly divided in two groups: high dosage with an average age of 24±3.047 and an average weight of 58.60±7.576; the second group was the low dosage group with average age of 23.60±3.439 and an average weight of 61.93±5.311. In the first week, Subjects ingested a placebo (orange juice) and in the second week, subjects of the low dosage group ingested 0.03 grams of β-alanine per kg of their bodyweight; While the participants in the high dosage group took 0.1 grams of β-alanine per kg. 1km cycling time trial test was conducted. Performance Time, RPE and Recovery Heart Rate was measured at rest, immediately, 4 minutes and also 10 minutes after cycling, with Performance Time obviously being measured just after. Data were analyzed using a mixed ANOVA. The results showed that RPE significantly decreased in both groups but the difference between groups was not significant. Performance Time of cycling 1 km improved in both groups that in high dosage group was significant but in low dosage group was not. Also Recovery Heart Rate measures were significantly decreased in both groups and the difference between the groups was significant . β-alanine even with a low dose can decrease heart rate and RPE But only high dosage can improve performance.

Considering the importance of preventing heart disease and conflicting information about the effect of exercise training on glutathione peroxidase and catalase gene expression, the aim of this study was to investigate the effect offour training methods on Glutathione peroxidase and catalase expression in heart tissue of rats. For this purpose, 40 male wistar rats with age of 8-weeks were randomly divided into 5 groups including control group, moderate intensity training, high intensity training, high intensity interval training and moderate-intensity swimming training. To analyze of the data, one-way ANOVA and Tukey was used. The results showed that there was a significant increase in the Glutathione peroxidase and catalase expression as a result of all four exercise training program compared to the control group (P=0.001), Also, a significant increase in GPX expression was observed between HIIT and HIT groups compared to MIT and MIST groups (P=0.001). On the other hand, there was a significant increase in CAT expression between MIST group compared to MIT and HIIT groups (P=0.001 and P=0.030, respectively) and between HIT group compared to MIT and HIIT groups. There was also a significant difference between MIT and HIIT groups (P=0.001). All four training methods were able to improve the antioxidant system, causing favorable changes in the heart tissue of Wistar rats. It seems that HIT، HIIT & MIST by creating a beneficial adaptation in the antioxidant system, has made the body more resistant to the oxidative stress and has a more favorable effect on the heart tissue.

Aging is often associated with a progressive loss of muscle strength and an increase in fat mass. High-intensity interval training may improve muscle strength, but remains largely unstudied in ageing participants. Therefore, the purpose of this study was to determine the effects of eight weeks of low-frequency high-intensity interval and L-citrulline supplementation on myostatin, aerobic power, muscular strength and endurance and body fat in older men. 30 inactive old men randomly divided into three groups: high-intensity interval training (HIT), citrolin (CIT) and high-intensity interval training+citrolin (HIT+CIT). HIIT was performed for 8 weeks and 2 sessions per week that included 30 seconds cycling exercise on ergometer (intensity of 85-90% HR reserve). CIT supplement consumed in single 8 g-dose alternateve day. Results showed that there was significant decrease for myostatin in HIT+CIT and for body fat in HIT+CIT and HIT than CIT. Muscular strength and aerobic power significant increase in HIT+CIT and HIT than CIT. HIT+CITgroup showed significant increase compared to CIT. In conclusion, low-frequency HIIT alone and combined with L-citrulline seems to induce greater improvements in muscular strength and mass factors and aerobic performance in inactive elderly men. Therefore, low-frequency HIIT+CIT can be considered as effective program to prevent or reduce sarcopenia among elderly.