فصلنامه فیزیولوژی ورزشی
پیاپی 50 (تابستان 1400)

Obesity leads to metabolic diseases, and adipose tissue considered as one of the regulator of metabolism. Recent researches has demonstrated that some stimulants cause beiging of subcutaneous adipose tissue, resulting in thermogenesis and some other features of brown adipose tissue. The activation of β3-adrenergic receptors in the adipose tissue that occurs as a result of exercise also leads to the activation of UCP1 and is one of the most effective methods to combat obesity. Becacuse exercise is known as a cheap lifestyle intervention and the benefits of using it as a non-pharmocological treaetment in improvement of metabolic diseases, including obesity, have been well illustrated, Examining the molecular mechanisms of exercise is essential. One of these molecular mechanisms is the increase in thermogenesis due to exercise, which can be caused by the release of various types of cytokines. Due to the physical activity of the UCP1, it increases as the beige process occurs in the subcutaneus white adipose tissues. Increase in various cytokines and important genes involved in this process, which occur with different types of exercises at various levels, is a promise that exercises could be considered as one of the possible treatments for obesity and metabolic syndrome.

Alzheimer's disease is a progressive disorder of the nervous system. Aβ-induced degradation reactions in the CNS result in neurotrophic factor abnormalities, which may in turn facilitate the development of amyloid pathology. The effects of exercise on these factors have been taken into account, however, an understanding of how it works needs further investigation. Therefore, the purpose of this study was to investigate the effect of aerobic training on Trk-B, PKC and AKT in hippocampus of male rats with Alzheimer’s Disease. In this experimental study, 36 adult male rats (8 weeks) with an average weight of 195 ± 20 g were randomly divided into 3 groups: Alzheimer's Disease (AD), Alzheimer's Disease + exercise training (ADT), and control (C). The induction of Alzheimer's disease was induced by intrahippocampal injection of Aβ1-42. Aerobic exercise was performed for 4 weeks, 5 sessions per week. 24 hours after the last training session, animals were either subjected to behavioral testing or killed, and their hippocampus was extracted for further experiments. One-way ANOVA was used to analyze the data. The results showed that the ADT rats spend significantly more time in the target quadrant compared to the AD group in the probe test (p ≤ 0.05). Also, Trk-B, PKC and AKT levels decrease following injection of Aβ1-42 (p <0.001). Aerobic exercise increased Trk-B, PKC and AKT levels compared to AD rats (p≤0.05). Therefore, aerobic exercise seems to help improve the spatial memory by activating the TrkB- PKC-AKT signaling pathway.

The aim of the present study was to constructing a norm of health-related fitness in men aged 18 - 60 years old in Rasht city. The study was descriptive and performed using the survey method in which 384 men aged 18-60 from Rasht city were systematically selected using cluster sampling method. Weight, height, BMI, WHR, skinfold of 3 points, aerobic power, handgrip strength, trunk flexibility, abdomen and shoulder girdle muscular endurance were measured using the standard tests. In order to analyze the data, descriptive statistics, z-score, and percentiles were used in each test and the norm of each fitness factor was constructed according to the percentiles. Mean aerobic power (48.14 ml/kg/min), handgrip strength (54.28 kg), abdomen muscular endurance (34.77 sit-ups), shoulder girdle muscular endurance (32.39 push-ups), trunk flexibility (26.52 cm), body fat (25.76 %), BMI (26.38 kg/m2) and WHR (0.96) of the subjects were observed. The results showed that most 18-60 aged men in Rasht city have middle status in relation to body composition and are relatively good in relation to other fitness factors. Fortunately, in most of the physical fitness factors, Rashti men are in a better status than other regions of Iran and even other countries. However, there is little data on the norm of physical fitness of the population of the age group studied in this study (aged 18-60) in Iran, which suggests that studies be conducted in this regard.

The main purpose of this study was to compare the effect of an eight-week LIET and HIIT, on the amount of HIG2 gene and TG content of visceral lipid tissue in wistar male rats affected by NAFLD. The present research was performed on 40 wistar rats affected by NAFLD. The rats were divided into four-ten groups Healthy Control (Standard Diet), control, LIET and HIIT (High fat diet). After 16-weeks of using special diet and end of practical or training period. HIIT training protocol consisted 90% and The LIET training protocol composed of running with 45% maximum speed intensity. HIG2 gene expression by real-time PCR technique and TG measurements visceral lipid tissue was done by auto analyzer (BT3000 model). Analysis of data revealed that there is no significant difference in HIG2 gene expression among training groups compared to control groups (p=0.05). The increasing significance was observed in HIG2 gene expression amount merely in control group (p=0/039) compared to experimental group. There was a significant deference in the amount of TG content between control group and LIET group (p=0/001) and between control group and HIIT group (p=0/001) and between LIET and HIIT group (p= 0/003). It can be concluded that considerable continuation of fatty diet during the training and the influence of exercises on the amount of TG; and on effect on HIG2 gene expression demonstrate that each of the tow training program, independent of HIG2 gene, had an effect on visceral fat content in NAFLD affected rats.

Obesity suppreses muscle mitochondorial biogenesis and the effects of HIIT and Q10 in this area remains to be more investigated. The aim was to investigate the concomitant effects of HIIT and Q10 supplementation on two indices of mitochondorial biogenesis in obese male rats’ skeletal muscle.48 male rats[16 weeks, obese group weight: 272to372gr(308.8±22.36gr); normal weight: 140 to 197gr (158.622.21gr)] were randomized into six groups including normal weight, obese reference, obese control, obese HIIT, obese Q10 and obese HIIT concomitany with Q10 groups. Obesity was induced by high fat diet. Q10 supplentation 500 mg/kg.bw.day and HIIT(10 activity bouts for 4 min at 85-90% of v VO2 peak with 2min rest intervals) were done for 12 weeks. Western blot and spectrophotometery methods were respectively used to quantify the variables and the data were analyzed using one-way ANOVA. A lower soleus PGC-1α content were observed in obese reference(P=0.001) and also obese control(P=0.003) groups compared to normal weight group with higher citrate synthase activity (P=0.039,P=0.031 respectively) in both of them. HIIT(P=0.001), Q10(P=0.001) and their concomitment (P=0.001) elevated PGC-1α expression to levels even higher than normal weight group, with more efficacy were noted for HIIT rather than Q10(P=0.017). None of interventions changed CS activity (P>0.05). It can be concluded that obesity suppreses muscle mitochondorial biogenesis and HIIT efficiently compensates this condition and even elevates muscle mitochondorial biogenesis compared to normal weight rats. Q10 supplementation has also beneficial effects, although weaker than HIIT. However, more investigations remain to be done because of similar evidence and study limmitations.

The purpose of the current study was to investigate the effect of HMB-FA supplementation on muscle damage indices in elite wrestlers. A total of twenty wrestlers selected in two supplement- exercise (n=10) and placebo- exercise (n=10) groups to participate in a simulated wrestling protocol. Subjects were randomly assigned to receive either 3g/d of HMB-FA or a placebo. Blood samples to measure serum creatine kinase (CK) and lactate dehydrogenase (LDH) were taken before taking the supplement, after taking the supplement, immediately after the first repetition of the simulated wrestling protocol, immediately after the third repetition of the simulated wrestling protocol, immediately after the fifth repetition of the simulated wrestling protocol. The perceived recovery status (PRS) was assessed immediately before the first, second, third, fourth, and fifth repetitions of the simulated wrestling protocol. The results were analyzed using ANCOVA analysis of covariance and analysis of variance with repeated measures. The results of this study showed that the values of muscle damage indices, including CK, LDH decreased significantly more than the placebo group in the HMB-FA group (p<0.05). There was also a significant change for PRS, which significantly decreased in the placebo group compared to HMB-FA (p<0.05).Therefor, it can be concluded that HMB-FA supplementation appears to improve muscle damage indices in wrestlers' simulated wrestling protocol.