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Background: The immune properties of mothers’ milk are well known. But the effects of physical activity on humeral immune properties of mothers’ milk is still undetermined. Therefore, reports on the impact of exercise on IgA concentrations of mothers’ milk is controversial. The purpose of the present study was the investigation of the effects of selected aerobic exercises in maximum intensity of 60-70% of heart rate reserve on IgA concentrations in breast milk as well as body composition. Method: In this research, 28 sedentary women (29±5.7 years; VO2max 36±4 ml/Kg/min), divided into two exercise and control groups through random sampling, took part. The exercise group performed some particular exercises for 10 weeks whereas the control group did not do so. Milk samples were taken from both groups and measured by the ELISA method. Body composition was also measured in different stages of the study. Results: In the rest status, the two groups were identical in terms of IgA concentrations (p= 0.549) and body composition (p=0.204). IgA concentrations under exercise load of 60% (p=0.060) and 70% (p= 0.001) of the HRR respectively showed a significant increase as compared to the resting status mean values in the two groups. Body composition variables were only of significant values in terms of comparing the general effects, only in the factors of group (p=0.003) and reciprocal effect of the grouping - the duration of the exercises (p=0.024). Conclusions: The results of this research show that, under the effects of moderate intensity exercise, the mothers’ secretory immune system experiences some changes. Therefore, IgA concentrations in the milk increase. In addition, with the reduction of fat weight, the decrease of fat mass percentage, and increase in the body density, the level of the mothers’ aerobic fitness is increased, which is in no contradiction with their lactation performance.

Purpose: On the other hand, fatigue is one of the most important indicators of aging syndrome. This study aimed to investigate the relationship between the level of physical activity and fatigue in elderly residents of rest homes in Tehran. Method: This was a descriptive correlational study in which 20 rest homes located in Tehran province constituted the study population. By visiting rest homes, the eligible subjects were chosen. Physical activity was measured by the Physical Activity Scale for the Elderly (PASE). The FACIT Fatigue Scale is a short, 13-item, easy to administer tool that measures an individual’s level of fatigue during their usual daily activities over the past week. Nutritional status was evaluated by mini nutritional assessment (MNA). Results: The results of statistical analysis indicated a significant and positive correlation between PASE and FACIT scores (r=0.48, p<0.01) while, there was a significant negative correlation between FACIT score and age (r=-0.23, p<0.01). Also, there was a significant positive correlation between MNA and FACIT (r=0.40, p<0.01). In addition, a significant positive correlation was found between MNA and PASE score (r=0.31, p<0.01). Conclusions: The findings of this study indicate that holding sports classes under the supervision of exercise physiologists is an essential matter to increase health and prevent age-related complications in elderly residents of Tehran rest homes.

Background and Purpose: Increasing participation in sports activities has increased the incidence of sports injuries. Considering the short and long term complications of sports injuries, the need to prevent them is one of the most important goals. The purpose of this study was to evaluate the effects of ankle bracing on the ankle plantar flexor muscles activity in different foot position during drop landing with and without fatigue. Method: Fourteen female college athletes participated in this study. Five models of 5 and 10 degrees medial, lateral and normal wedged insoles were used to simulate the position of the feet on the ground at the wrong landing technique. The Medial Gastrocnemius (MG) and Peroneus Longus (PL) muscles activity 100 ms before and 100ms after landing in different foot position before and after muscles fatigue with and without ankle bracing was recorded with surface electromyography. Repeated measures ANOVA was used for statistical analysis (p≤0.05). Results: The results showed that the effect of time on the activity of MG and PL muscles in landing with brace was significant, so that the MG muscle before landing and PL muscle after landing had a higher activity in both times before and after fatigue (p≤0.001). The activity of this muscles was not significant when using the ankle brace during landing in different positions (p˃0.05). Conclusions: According to the results of this study, lace-up brace can help to increase muscles activity when they were fatigue, while the using of brace does not affect muscle activity when landing perform in different positions without fatigue. According to the results, In the case of a suggestion to use brace for athletes, all aspects of using this equipment should be considered.

Introduction: Training at altitude or in a hypoxic environment has gained attention among athletes, coaches, and scientists to enhance sea-level performance. However, the efficacy of “Living-Low, Training-High, Training-Low” (LLTHTL) strategy to escalate the mechanisms associated with enhancing performance in the human athletes is still unknown. The present study aimed to investigate the effect of the LLTHTL on Hypoxia-Inducible Factor-1 alpha (HIF-1α) and peroxisome Proliferator-activated Receptor-Gamma Coactivator-1alpha (PGC-1α) levels in elite endurance runners.  Methods: The study has a crossover design in University laboratory. Eight elite male runners (Mean±SD age: 24.50±3.96 years; Mean±SD height: 179.75±4.62 cm; Mean±SD body mass: 67.37±3.42 kg; Mean±SD body mass index: 20.85±1.11 kg/m²) took part in the research. After 4 weeks of Living-Low (LL), the athletes performed 4 weeks Training-High (TH) and then, 3 weeks training-low (TL). Main Outcome Measures: Anthropometric parameters, time trial (1500 m), PGC-1α, and HIF-1α levels were measured in four different time points: pre-LL, post-LL, post-TH, and post-TL.  Results: There were no significant differences between the 4 time points for body mass and body mass index (P>0.05). The time trial was improved significantly (p <0.001) at post-TH as well as post-TL compared with the pre-LL and post-LL. TH decreased HIF-1α level but did not affect PGC-1α. Besides, TL increased both HIF-1α and PGC-1α.  Conclusion: Training at altitude reduces HIF-1α and training at sea-level increased PGC-1α and HIF-1α levels. Both types of training induced an improvement in the time trial. Athletes and coaches seek advice on the effective training strategy to enhance performance at different altitudes.

Purpose: The purpose of this study was to analyze the public relations status of Sports and Youth Organization in Kohgilouyeh and Boyer Ahmad province. The present research was applied and study was a consecutive hybrid exploratory strategy and is implemented by qualitative content analysis and questionnaire quantitative survey. Method: Statistical society in qualitative section, ten people in Kohgiluyeh and Boyer Ahmad provincial authority of sports and youth, and in quantitative personnel in public relations department and 46 provincial active board and sports reporters in the province in total there were 150 people. Data collection tool was a face-to-face interview and a researcher-made questionnaire. Based on the findings of the qualitative section, a questionnaire was designed and its face and content validity was evaluated by several experts in the field of public relations and sport management and its construct validity was done by confirmatory factor analysis and its reliability was Cronbach's alpha coefficient of 0/94. Results: The qualitative data were analyzed by qualitative data encoding method and in quantitative part of descriptive statistics, frequency table was included and in the inferential part Friedman test was used. Conclusions: The results showed that the public relations status of Sports and Youth Organization in this province was below average, and Friedman's test showed that the importance, rank, and status of public relations were totally different.