درخت حوزه‌های تخصصی

Purpose: the etiology of children obesity can be varied. Adipose tissue is an active tissue that secretes proteins such as TNF-α, IL-6, leptin, and adiponectin. The purpose of this study was to investigate the effect of short-term sprint interval training on serum levels of adiponectin, leptin, TNF-α, IL-6, insulin, and lipid profile in overweight boys. Method: a number of 30 overweight male students (with a mean age of 9.93±0.2 and BMI of 27.73±0.2) were randomly assigned to the control group (n=15) and sprint interval training (n=15). The subjects of the experimental group did the training for eight weeks, as the control group was engaged in doing their daily activities without intervention. Measurement of anthropometric indices and fasting blood collection were performed (to measure insulin, leptin, adiponectin, TNF-α, IL-6, cholesterol, LDL, HDL and TG) one day before and one day after the training program. Results: the results of the present study indicated that 8 weeks of sprint interval training significantly decreased weight and BMI in overweight children (P<0.001). In addition to weight and BMI reduction, levels of TNF-α, IL-6, leptin, insulin, cholesterol, triglyceride, and LDL significantly reduce the following eight weeks of the sprint interval workout (P< 0.001 for all), while adiponectin and HDL levels increase (P<0.001, P<0.01, respectively). Conclusions: in general, the present study demonstrate that sprint interval training which is a new way of physical activity exerted a positive effect on most of components contributing to children obesity.

Purpose: Creatine is the most important and commonly used supplement in athletes. The purpose of this study was to investigate the simultaneous effect of moderate altitude and short-term Creatine supplementation on musculoskeletal damage indicators in male climbers. Method: 16 male hikers with at least 2 years of hiking experience selected. Subjects (age 30.6±6.3 yrs.), (height 178.3±6/4 cm), (weight 77.6±11.25kg) were randomly divided into experimental (Creatine supplement) and control groups (placebo). The experimental group consumed 20 gr/day of the supplement for 5 days, while the control group received a placebo. The first blood samples were taken before the hiking session at the location of program. Hiking program consisted of ascending to Tochal peak at an altitude of 3961m. The second blood samples were taken after returning from the peak at an altitude of 3750 meters. The results were analyzed by SPSS software using independent t-test and K-S test with a significant coefficient of 0.05. Results: The results showed that there was a significant difference between LDH and AST enzyme levels in post-test compared to pre-test in both AST (P = 0.13) and ALT (P = 0.001) levels Control group. Also, climbing to 4000 m altitude with Creatine supplementation had no significant effect on LDH (P = 0.78) and AST (P = 0.86) levels between groups. Conclusions: The results showed that changes in muscle damage enzymes are independent of Creatine supplementation.

The purpose of this study is to investigate the effect of brand, design and price on the perceived quality and re-intention of consumers to buy sport brand shoes. This is an applied research conducted as a descriptive correlational study in field form. The statistical population of this study included all physical education students across different educational levels in Iran. In this research, 720 questionnaires were collected by random cluster sampling. Structural Equation Modelling (SEM) with PLS software was used to analyse the data of this research. The results of this study show that design with a coefficient of 0.36, price with 0.27, and brand with 0.26 have a significant effect on quality perceived by customers. The results of this research also show that perceived quality with an effect coefficient of 0.49 has a significant effect on customers’ purchase intention. Generally speaking, it can be concluded that the components of design, price, and brand of sport shoes for Iranian physical education students are very important. Famous brands in the world need to pay particular attention to these components to tap into this lucrative market in Iran and increase their re-purchasing intention by influencing consumers’ perceived quality.