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Background : There are conflicting findings regarding the effect of various training modalities on the cardiovascular disease mechanisms induced by undesirable modifications in extracellular matrix (ECM) factors such as MMP-9 and TIMP-1. Aim: This study was conducted to investigate the effect of different training protocols on the MMP-9 and TIMP-1 gene expression in the myocardium of Wistar male rats. Materials and Methods: Forty-eight adult Wistar male rats (aged: 8 weeks) were randomly allocated into two control (Con8w/base, n=8; and Con16w/end control, n=8) and four training groups (MICT, n=8; PICT, n=8; HIIT, n=8; and MIST, n=8). The training protocols consisted of 8 weeks (5 days/week) of Moderate-Intensity, Continuous Training (MICT: 37 min running with 65% vVO 2 max), Moderate-Intensity, Swimming Training (MIST: 30 min free-swimming), Progressive-Intensity, Continuous Training (PICT: 28 min running with a progressive increase in the incline of the treadmill by 2% per week), and High-Intensity Interval Training (HIIT: four running bouts 4 min with 90 to 100% vVO 2 max + 3 min with 50-65% vVO 2 max). Myocardial samples were isolated 24 hours after the last training session. Gene expression was determined using the real-time PCR method. All data (M±SD) were analyzed by one-way ANOVA and Tukey's post-hoc tests at α ≤0.05. Results : There were significant differences between MMP-9 and TIMP-1 expression in the animals myocardium after different exercise training protocols ( P <0.01). The lowest and highest MMP-9/TIMP-1 ratios were in the HIIT and MICT protocols, respectively. Conclusion: According to our findings, the HIIT protocol may play a more influential role in enhancing myocardial ECM-remodeling and fibrosis indicators during lifespan than the other exercise protocols.

Background: Anodal transcranial direct current stimulation (a-tDCS) is a new neuro-modulatory technique.Aim: This study aimed to investigate the effect of a-tDCS on dynamic balance after exhaustion.Material and Methods: Fifteen endurance-trained men voluntarily attended five separate sessions. In the first session, Maximal aerobic speed (MAS) was measured. Then, the participants were randomly assigned to four different conditions: 1. Mental fatigue (MF)+a-tDCS, 2. MF+sham (s-tDCS), 3. a-tDCS, and 4. s-tDCS. In each session, after dynamic balance measurement, the participants were exposed to the conditions and received 20 min of anodal tDCS over the dorsolateral prefrontal cortex (DLPFC). Then, the participants performed a submaximal endurance activity at 70% of MAS until exhaustion. Immediately after exhaustion, dynamic balance was measured again.Results: After exhaustion, the dynamic balance of the right leg under the a-tDCS condition was significantly higher than the MF+s-tDCS (P= 0.008). The dynamic balance significantly decreased from pre- to post-test in MF+s-tDCS and s-tDCS conditions (P= 0.0001). In the left leg, the dynamic balance under the a-tDCS condition was significantly higher than MF+s-tDCS (P= 0.025).Conclusions: Anodal stimulation of the DLPFC could be beneficial for the dynamic balance and may have a protective effect against the negative consequence of exhausting activity on the dynamic balance in endurance-trained men.

The aim of this research was to determine the relationship among transformational leadership style with organizational culture and organizational commitment. The population consists of 745 the employees of the Ministry of Youth and Sports of Iran. The sample size of 256 staffs was determined using stratified random sampling. In order to collect the needed data, three Transformational Leadership, Organizational Culture and Organizational Commitment Questionnaires were used. The validity of these questionnaires was confirmed by foreign and domestic researches. Cronbach's alpha reliability test of transformational leadership, organizational culture and organizational commitment were respectively 0.97, 0.97, and 0.92. In addition, data were analyzed using statistical tests such as descriptive statistics, Kolmogorov Smirnoff, Pearson correlation coefficients using SPSS Software. The findings of this study showed that there was a positive and significant relationship between transformational leadership and organizational culture (p≤0.01, r= 0.80). Besides, there was a positive and significant relationship between transformational leadership and organizational commitment (p≤0.01, r= 0.46), too. Likewise, there was a positive and significant relationship between organizational culture and organizational commitment (p≤0.01, r= 0.57). However, organizational culture is stronger predictor than transformational leadership for organizational commitment. Finally, in accordance with the responses of staffs of the Ministry of Youth and Sports, it can be said that if leaders create an organizational culture in which creativity and satisfaction were high as well as to taking advantage the organizational rewards and job good conditions, employees would be able to stimulate higher levels of organizational commitment.

Purpose: Delayed onset muscle soreness (DOMS) is pain and stiffness that occurs several hours to several days after unusual or intense exercise. It is thought that this exercise causes small damage (micro trauma) to muscle fibers. The aim of the present study was to compare the effects of high-intensity resistance training and resistance retraining on serum levels of some indices of muscle damage in inactive young girls. Method: Twenty-four healthy inactive young girls voluntarily participated in the present study. They then randomly divided into two groups of 10. The muscle injury protocol included five stations of biceps and shoulder presses with a barbell, squats, chest press, and leg press. Each movement consisted of three sets of 8 to 12 repetitions, with an intensity of 75% of one repetition maximum. Serum levels of creatine kinase, lactate dehydrogenase, and aspartate aminotransferase enzymes were measured before the activity and at intervals of 1, 26, and 48 hours after it. Analysis of variance with repeated measures and independent t-test were used to analyze the data at a significance level of p≥0.05. Results: there was no significant difference in the changes in creatine kinase, lactate dehydrogenase, and aspartate aminotransferase between the two groups at different stages of measurement after retraining (p<0.05). Conclusion: According to the results of the present study, it can be concluded that resistance training cannot be a significant influencing variable on the amount of muscle damage. However, more research in this field is needed.