نشریه فیزیولوژی ورزش و فعالیت بدنی
سال پانزدهم شماره 2 (تابستان 1401)

The effects of exercise adaptation on improving the purine nucleotides components are inevitable, and physical activity improves the purine nucleotide salvage pathway. The impact of different training methods, especially the very high intensity exercise and very short bouts and short training periods is not well understood. Therefore, the present study aims to investigate the possible compatibility of high intensity interval training on hypoxanthine, xanthine, hypoxanthine-guanine phosphoribosyltransferase (HGPRT) and serum uric acid in a short-term.

In this semi-experimental study, eighteen healthy, untrained, male with mean and standard deviation were age 21.95 ± 2.34 years old and BMI 22.95 ± 2.84 kg/m2 eligible volunteers were randomly divided into control and training groups. The training group cycled the bicycle ergometer with maximum intensity for two weeks (three sessions per week) with 15-second repetitions and a 4-minute rest between the sets. Blood samples were collected for measuring HGPRT, hypoxanthine, xanthine and uric acid before and 48 hours after the last training session, and data were analyzed using analysis of covariance and Alpha level of 0.05.

A significant increase was found in the levels of hypoxanthine (P = 0.001), xanthine (P = 0.001) and statistically significant reduction was found in uric acid (P = 0.02), and HGPRT enzyme was not significantly different the two groups.

The results of this study indicated that high intensity interval training causes the excretion of more purine bases such as hypoxanthine and xanthine, and reduce uric acid at rest is possibly increase antioxidant capacity.

Mitophagy can assist in mitochondrial quality control. The aim of this study was to investigate the effect of training on mitochondrial mitophagy factors in obese male rats.

In this experimental study, 40 male rats (weight 120 ± 20 g) after inducing obesity with high fat diet (for 10 weeks), eight rats from the high-fat diet group (O) and eight rats of the standard dietary group (C) to investigate the induction of obesity were described and other obese rats were randomly divided into three groups: obesity control (OC), moderate intensity continuous training (MICT) and high intensity interval training (HIIT). The HIIT protocol includes 10 bouts of 4-minute activity with intensity of 85-90% vo2max and 2-minute active rest periods and MICT protocols performed five sessions per week, with intensity of 65-70% VO2max for 12 weeks. Bcl2 and parkin levels were measured by gel electrophoresis and western blotting. Data were analyzed by One-way ANOVA and post hoc Tukey at P ≤ 0.05.

The results showed that both HIIT and MICT training significantly increased bcl2 and PARKIN of Soleus muscle in comparison with the control group (P < 0.05). However, there was no significant difference between the two groups of HIIT and MICT in bcl2 and PARKIN levels of Soleus muscle in obese male rats (P > 0.05).

According to the results, it seems that HIIT and MICT can help reduce mitochondrial degradation and impairment in skeletal muscle during obesity.

The liver is one of the most sensitive tissues targeted by exercise-induced oxidative stress, and hepatic aminotransferases are critical indicators for determining liver cell damage; Therefore, the present study aimed to compare the effect of eight weeks of TRX and traditional resistance training on some liver enzymes (aspartate aminotransferase and alanine aminotransferase) in inactive women.

In this quasi-experimental study, 28 inactive girls with a mean age of 21.07 ± 1.41 years and a body mass index of 22.52 ± 4.25 kg/m2 were randomly divided into three groups: TRX training, traditional resistance training and control. Experimental groups conducted the traditional resistive training and TRX three sessions a week for eight weeks, While the control group did not participate in any training program during the study. Blood samples were taken from all subjects before starting protocol and 48 hours after the last training session and were used to analyze Aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Data were analyzed using Kolmogorov-Smirnov test, dependent t-test and one-way analysis of variance, and the significance level was considered P < 0.05.

The results showed that there was no significant difference in serum levels of AST and ALT enzymes from pre to posttest in TRX, traditional resistance and control groups (P > 0.05). Also, no difference between groups was observed in any of the factors (P > 0.05).

The results of the present study showed that there was no significant difference between TRX training and traditional resistance to serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in inactive women. Therefore, the effects of TRX and traditional resistance training on liver enzyme indices were the same and no difference was observed between these two types of training methods.

little is known about the concomitant effects of HIIT and Q10 supplementation in modification of the mitochondorial biogenesis and function in obesity conditions. The aim of this study was to investigate the concomitant effects of HIIT and Q10 supplementation on soleus muscle mitochondorial content as well as NRF2, SIRT-1 and Tfam levels in obese male rarts.

48 rats randomized into six groups of lean, obese reference, obese control, obese+HIIT, obese+Q10 and obese concomitant (HIIT+Q10). Obesity was induced by high fat diet and HIIT) were done for 12 weeks (five sessions/week, with 10 intrval bouts for four min at 85-90% of v VO2 peak each session), while Q10 was consumed 500 mg/kg.bw daily. Data were measuered using western blot and Mitotrackervmethods and were analyzed by one-way ANOVA.

Mitochondorial content (P = 0.049) as well as NRF2 (P = 0.002), SIRT-1 (P = 0.007) and Tfam (P = 0.040) levels were significantly lower in obese control than lean group. Mitochondorial content and SIRT-1 levels of three intervention groups of obese+HIIT (P = 0.001), obese+Q10 (P = 0.001) and obese concomitant (P = 0.001) were significantly higher than obese control group and even could precede lean group values (with exception for mitochondorial content in obese+Q10 group (P = 0.001)). Moreover, only in both groups of obese+HIIT ( P= 0.033), and obese concomitant (P = 0.038), NRF2 levels were significantly higher compared to obese control group. However, in none of the intervention groups the Tfam levels had significant differences compared to obese control group (P > 0.05 in all three cases).

Obesity likely suppresses soleus muscle mitochondorial biogenesis, or at least increases the removal rate of pre-existing mitochondria. However, HIIT as well as Q10 supplementation seems to partially capable to restore this down regulation, with a greater effects expected for HIIT. However, more investigations remain to be done due to lack of similar evidence and study limitations.

Due to the intervals' nature of soccer, the aim of this study was to evaluate intermittent protocol of incremental laboratory test in measuring the physiological parameters of soccer players.

Eighteen young soccer players (Mean ± SD; age 16.78 ± 0.78 years, weight 61.33 ± 9.44 kg, height 177 ± 6.75 Cm) voluntarily participated into two incremental laboratory tests (continuous and intermittent protocol) on the HP Cosmos Treadmill with 48-hour interval and then Bangesbo field test was performed. The subjects' cardiopulmonary parameters were measured by gas analyzer, metalyzer3b model, and blood lactate before and after the tests with lactometer Scout model. Statistical analysis was performed by ANOVA Repeated Measure, paired t-test and Pearson correlation coefficient at the significant level P ≤ 0.05.

There was no significant difference between the physiological factors of continuous and intermittent tests, but there was a significant difference between the distance at continuous and intermittent tests (P = 0.031). There was a significant positive relationship between the performance of the Bangesbo test with the maximum oxygen consumption (r = 0.64, P= 0.011) and distance (r = 0.62, P = 0.018) of the intermittent test.

The significant positive correlation between the maximum oxygen consumption of the intermittent test and the performance of the Bangesbo test, Higher distance in intermittent test and significant positive correlation between performance of Bangesbo test and distance of intermittent incremental test; It may be explained by the similarity of the intermittent test to the interval component of the playing soccer and this observing suggest to consider component of athlete's activity when defining the incremental test.

Depending on the intensity and duration of activity, aerobic exercise leads to changes in hemodynamic factors and the hemostatic system in hypertensive patients, which can be expected to change if blood flow is restricted during exercise. Therefore, the purpose of the present study was to investigate the response of some hemodynamic and coagulation indicators to aerobic exercise with and without blood flow restriction in hypertensive patients.

10 hypertensive patients participated in two sessions of aerobic exercise (five bouts, two minutes of exercise at a speed of four km / h /one minute of inactive recovery) with and without blood flow restriction in a cross-over design. Blood pressure was measured before, immediately, five, 10, 15, 30 and 60 minutes after exercise. Platelet counts, Prothrombin Time and activated Partial Thromboplastin Time were taken before, immediately, 30 minutes and 24 hours after exercise. Heart rate and rate of perceived exertion were also measured at different times of exercise.

The effect of time was significant on all measured factors (P < 0.001) except platelet counts (P = 0.055), while the time-condition interaction was non-significant on other factors (P > 0.05) except heart rate (P = 0.011).

Based on the results, blood flow restriction increased hemodynamic factors and decreased clotting time in hypertensive patients, but the differences between aerobic exercise with and without blood flow restriction were not significant, so it seems that exercise with limited blood flow does not pose an additional risk on the cardiovascular system and coagulation factors of middle-aged people with hypertension.

Non-alcoholic fatty liver disease (NAFLD) is strongly associated with altered levels of inflammatory cytokines and increased metabolic abnormalities. In this study, the effect of combined training on serum concentrations of proinflammatory cytokines interleukin 18 (IL18), anti-inflammatory interleukin 10 (IL10) and metabolic syndrome-related factors in elderly women with fatty liver was investigated.

twenty-four elderly women with NAFLD were selected purposively and were randomly divided into training (n = 12) and control (n = 12) groups. Combined training was performed for ten weeks. Using ZellBio kit, IL18 and IL10 levels were measured by ELISA and fatty liver levels by ultrasound procedure. Blood and anthropometric factors were measured as well. Statistical analysis was performed using paired samples t-test and Wilcoxon, covariance and Spearman correlation procedures.

Decreased and increased serum concentrations of interleukin 18 (P = 0.00) and interleukin 10 (P = 0.00) were observed in the training group compared to the control group, respectively. Also, weight, waist circumference (P = 0.00) and metabolic markers including triglyceride (TG) (P = 0.00), insulin resistance index (HOMA-IR) (P = 0.01), liver fat (P = 0.00), aspartate aminotransferase (AST) (P = 0.04) and glucose (P = 0.00) levels were significantly reduced. Moreover, there was no significant difference between insulin (P = 0.11) and alanine aminotransferase (ALT) (P = 0.07) levels.

Combined training can improve the levels of inflammatory cytokines and reduce metabolic risk factors associated with non-alcoholic fatty liver and play an effective role in the health of the elderly by augmenting anti-inflammatory effects.

Making changes and fluctuations in the training components compared to repetitive training can lead to more motor learning based on the principles of system self-organization. The aim of the present study was to investigate the effect of differential and traditional training methods on electromyographic changes of lower body muscles in performing and learning crawl swimming.

In this study, 36 swimmers aged 20 to 25 years who had no experience in swimming training were selected as a sample and randomly divided into three groups of control, traditional exercises and differential exercises. Experiments of experimental groups in 12 sessions, during which,they learned to do breaststroke in a traditional and differential way. Before and after 12 training sessions, the mean Muscle activity based on root mean square index (RMS) and the mean time of activity of the muscles of the right thigh, anterior buttock and internal twins of the swimmers were measured.

Based on the results of Bon Ferroni test, the mean RMS of Rectus femoris, Biceps femoris (P = 0.001), tibialis Anterior (P = 0.04) and Gastrocnemius (P = 0.005) of swimmers of the differential group is significantly larger than the control group in the post-test. This difference between differential and traditional group is also significant (P ≤ 0.05). But there is no significant difference between the control and traditional group (P > 0.05). In the post-test, only the activity time average of Rectus femoris in the differential group is larger than the traditional group (P = 0.046). The activity time average of tibialis Anterior muscle in both training groups are larger than the control group in post-test (P < 0.05), but there is no significant difference between differential and traditional training groups (P > 0.05). The activity time average of Gastrocnemius in the differential (P = 0.001) and traditional (P = 0.041) groups are significantly larger than the control group, but this difference between the differential training group and traditional training group is not significant (P > 0/05). Also, the activity time average of biceps femoris muscle in the differential training group is higher than the control group (P = 0.001), but there is no difference between the differential and traditional groups and also the traditional and control groups (P < 0.05).

The results of the present study indicate that differential exercises are more effective than traditional exercises in learning crawl swimming.

Endothelial dysfunction is the fastest symptom of vascular dysfunction in obese individuals also the onset of pre-hypertension development and along with lipid profiles can lead to dangerous cardiovascular diseases. The aim of this study was to investigate the effects of eight weeks circuit resistance training (CRT) on some endothelial markers, blood pressure and lipid profiles in pre-hypertensive obese women.

For this purpose, 24 pre-hypertensive obese women (age 44.73 ± 4.43 years, body max index 32.39 ± 3.8kg/m2, systolic blood pressure 13.21 ± 0.61 and diastolic 8.65 ± 0.33 mmHg) were randomly assigned to CRT and Control groups. CRT group performed circuit resistance training for eight weeks, three sessions per week and each session was 50 to 60 minutes. Resistance movements performs in the form of three circles and nine stations, including four upper body movements (chest press, lateral pull down, seated cable row, biceps cable curl) and three lower body movements (leg press, seated leg extension, leg curl), and two core-body movements (crunch and back extension) with 12-15 repetitions, which according to the recommendations of the American Heart Association was 40% 1RM for upper body and 60% 1RM for lower body movements. Control group didn’t have any training activities during the intervention. Blood pressure, anthropometric measurements and blood samples were collected 48 hours before the intervention and 48 hours after the last training session.

The results showed that eight weeks of circuit resistance training can significantly reduce body fat percentage (P = 0.005), waist to hip ratio (P = 0.043), systolic (P = 0.001) and diastolic (P = 0.002) blood pressure and triglycerides (P = 0.043) and significantly increase nitric oxide levels (P= 0.008).

It seems that eight weeks of CRT can decrease blood pressure by decline some lipid profile and also increase in nitric oxide levels by increase in capillary network in active muscles, and vascular flexibility.

An imbalance in the production of PGC-1α and myokines impairs the energy expenditure, increases adipocyte and develops metabolic pathologies, but physical exercise is able to regulate the secretion of myokines through PGC-1α. The aim of this study was to evaluate the effect of eight weeks of high-intensity interval training vs. continuous training on serum Irisin levels and expression of skeletal muscle PGC-1α gene in male rats with metabolic syndrome 32 Wistar male rats, with six weeks’ age and weight 150-180 gr, randomly divided into two groups including standard diet (n=8) and high fat diet (n=24). They were then placed on a pre-exercise diet for 12 weeks. 24 rats from high fat diet group were divided randomly into two groups including metabolic syndrome control (Ctr+MS), continuous running (CT-MS) and Interval running (IT-MS). Continuous and interval training for eight weeks were performed on 65-75 and 80-100% of the maximum speed on the treadmill for mice, respectively. The ELISA method for measuring serum Irisin levels and real-time PCR method for expression of PGC-1α gene were used. The data were analyzed by one-way analysis of variance (ANOVA), Tukey's post-hoc test and Pearson correlation at P < 0.05 level. After eight weeks of interval and continuous training, PGC-1α expression (P = 0.01 and P= 0.001) and serum levels of Irisin (P = 0.01 and P= 0.001) increased compared to the metabolic syndrome control group, and this increase was more evident in the interval group than the continuous group (P = 0.001). Muscle expression of PGC-1α was also positively correlated with serum Irisin levels in mice (P = 0.001, r = 0.8). It seems that the use of interval exercises can increase the expression of PGC-1α gene and Irisin as much as continuous exercise and possibly improve metabolic disorders in people with metabolic syndrome.