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Background: Water polo (WP) is a sport with great aerobic/ anaerobic physiological demands. There are few studies that have evaluated the physical demands during the WP game and its relationship with the physiological indices of aerobic fitness Aim: Our aim was to determine the aerobic/ anaerobic profiles of the WP athletes through specific test. Materials and Methods: WP male athletes participated in this study (24.5±5.6 years, 85.9±10.3 kg, 183.0±6.3 cm, n=23). The athletes performed an anaerobic WP test (TAnaWP) to determine the height (Alt- cm) of the 1st/ 15th/ 30th jumps, total time(s) of the jumps (TT30) and the fatigue index (FI). Blood lactate kinetics were determined immediately after (Lac0 min) and during the recovery period; Lac 1/ 3/ 5/ 8/ 12 min. They also performed an aerobic water polo test (TAerWP) to determine maximal oxygen consumption (VO 2 max) a heart rate (HRmax), peak blood lactate (Lacp) and the second lactate threshold (LL2). Results: The following results (in cm) were obtained in TAnaWP: Alt1st (44±6), Alt15th (32±7) and Alt30th (24±9); TT30 (56.9±9.5); FI (42.0±12.5%); (Lac0), (Lac1), (Lac3), (Lac5), (Lac8) and (Lac12) (5.2±1.7; 7.8±1.6; 9.0±2.0; 9.4±2.2; 9.2±2.7; 8.5±2.2 mmol/L, respectively). The mean maximal values for the aerobic test were: VO 2 max=44.4±5.3 ml/kg/min, HRmax=174.3±9.1 bpm, Lacp=8.6±2.1 mmol/L. The values obtained at LL2 were: 157.5±13.5 bpm/ 90.5±8.2% HRmax). Conclusion: The proposed tests may be a possibility to determining the physiological fitness of WP athletes.

Background: Observational learning is an effective pedagogical approach that can be used as a method to improve motor skill acquisition and also a useful instrument to promote psychological variables such as self-efficacy by emphasizing the motivational aspect. Although, little research is known about the model type and the observation conditions which will optimize learning. Aim: This study aimed to clarify the effect of using a combination of ideal model-observation and self-observation on self-efficacy and learning the forehand service of table tennis. Materials and Methods: Forty females were assigned to one of four experimental groups. All groups received the same instructions concerning how to perform the task, filled out a self-efficacy questionnaire, and then performed 10 pre-test trials. The acquisition phase included six sessions. The retention test was done 72 hours after the last acquisition session. Mixed ANOVA with repeated measures and Bonferroni post hoc tests were conducted, and one-way ANOVA was used to determine group significant differences. Results: The results indicated that observing the combination of skilled and learning models led to the highest self-efficacy for learning, compare with other experimental models. Also, significant learning of the task was shown in the acquisition phase in which the performance of all three experimental groups was clearly superior to the control group. Although in this phase there was no significant difference between the performances of two groups of combined skilled-learning and skilled. The results of the delayed retention test indicated that the performance scores of the combined skilled-learning group were significantly higher than the other three groups. Also, in this phase, the difference between the combined skilled self-observation and control or skilled groups was not significant. Conclusion: Demonstrating a skilled model is the most popular type of observational learning among the instructors and physical education teachers, it is suggested that adding a learning model to that leads to better performance and enhancing the self-efficacy.

Purpose: Low back pain (LBP) frequently occurs in daily life. Chronic low back pain (CLBP) is defined as pain in the lumbosacral area of the spine, of more than 12 weeks' duration. The aim of this study was to compare the effect of high-power therapy (HPL) with core stabilization exercise (CSE), in the treatment of CLBP. Method: A total of 30 female patients participated in this study, with a mean (SD) age of 32.23 (7.85) years. Patients were randomly assigned into two groups and treated with HPL (HPL group, n=15), and core stabilization exercise (EXS group, n=15). ROM of lumbar spine was measured by an inclinometer. The outcomes measured pain and functional disability using visual analog scale (VAS), Roland Disability Questionnaire (RDQ), and Modified Oswestry Disability Questionnaire (MODQ). Statistical analyses were performed to compare within and between group differences. Results: ROM, VAS, RDQ and MODQ showed significantly improve after 4-week treatment in both groups (P<0.05). However, there was no significant between-group differences in any variables (P>0.05). Conclusions: Both treatments were effective in the treatment of CLBP in female athletes.

Purpose: The objective of this study is to analyse various articles on the effect of various types of exercise on the angiopoietins family and angiopoietin-like proteins (ANGPTLs). Methods: PubMed, Science Direct, Scopus and Google Scholar databases were searched from 2000 to September 2020. After screening the articles, 19 articles that met the inclusion criteria were studied and analysed. Results: In our body, four types of angiopoietin and eight types of angiopoietin-like proteins have been identified, the functional method of some of them which are still not entirely understood. Angiopoietin-1 and angiopoietin-2 are essential regulators of vascular formation and maintenance. Angiopoietin-1 is found in perivascular and vascular cells within and around smooth muscle cells and plays an important role in growth, vascular stability, and pathological angiogenesis. On the other hand, angiopoietin-2 and angiopoietin-3 are mainly involved in inducing vascular regression, cell death, and inflammation. Angiopoietin-4, like angiopoietin-1, is responsible for the maturation, stabilization, and stasis of blood vessels. Conclusion: Studies show that exercise has a significant effect on increasing capillary density in the human body by increasing angiopoietin as one of the angiogenesis factors. In addition, there are many other benefits such as contribution to fat burning and treatment of coronary artery disease, cancer, asthma, and ischemia. More research is needed on the effects of different types of exercise training on angiopoietins.

Background: The SARS-CoV-2 virus is viewed as one of the defining crises of the current era, with various adverse ramifications for sports performance. Aim: The objective of the present study was to investigate the effect of aerobic exercise and caffeine supplementation on the cognitive performance and balance of college student-athletes recovered from COVID-19. Materials and Methods: Forty male student-athletes aged between 18 to 25 years from the Imam Khomeini International University of Qazvin were randomly assigned to four groups: 1. exercise + caffeine supplementation, 2. aerobic exercise + placebo, 3. aerobic exercise, and 4. control, in a pre-test post-test design. The Shapiro-Wilk test was used to check the normality of data distribution and covariance analysis was used for inter-group comparison. Results : The ANCOVA analysis showed significant differences in cognitive performance and balance among the four groups ( P <0.05). Pairwise comparisons using the Bonferroni post-hoc test showed statistically significant differences in cognitive performance and balance between the aerobic exercise + caffeine group versus the aerobic exercise + placebo group (P<0.05) and the aerobic exercise versus the control group ( P <0.05). Also, there was significant differences in mean cognitive performance and balance indices between AE+CAF versus CONT ( P <0.005) and AE+CAF versus AE ( P <0.005). Conclusion: The results of this study show that aerobic exercise with caffeine supplementation can improve cognitive performance and balance of student-athletes recovered from COVID-19.

Purpose: It has been well proven that type 2 diabetes is one of the most common non-communicable diseases leading to many complications and mortality every year. The aim of this study was to investigate the effect of resistance training on FTO and PPAR-y gene expression in muscle tissue of obese diabetic rats. Study design: This experimental study was performed on 12 male Wistar rats (10 weeks old and 220±20 g bodyweight). Methods: Animals received 6 weeks high-fat diet and then in order to induce type 2 diabetes an intraperitoneal injection of a single dose of 30 mg/kg freshly prepared streptozotocin (STZ) (Sigma, USA) solved in citrate buffer (pH 4.5) was performed. Diabetic rats were divided into two (Resistance and control) groups randomly. The resistance program included 6 weeks, 5 sessions per week. The muscle expression of FTO and PPAR-γ was measured using the real-time PCR method. Independent t-test and Analysis of covariance (ANCOVA) were applied to compare the means. Results: The muscle mRNA expression of PPAR-γ and body weight significantly increased after 6 weeks of resistance training (p=0.031, p=0.037; respectively) but there was no significant change in the muscle mRNA expression of FTO (p=0.317). Also, blood glucose significantly decreased in the training group compared to the control group (p=0.01). Conclusion: According to the results of this study, it can be noted that 6-week resistance training by decreasing glucose levels and increases insulin sensitivity, and the muscle expression of PPAR-γ plays a prominent role in the control and treatment of type 2 diabetes in obese patients.

Purpose: Skin is the most important organ of the body and maintains its integrity is critical in good health. Severe skin damage is life-threatening and repairing restores its tissue integrity and delay in it endangers health. According to the importance of wound healing and the fact that not treated wounds may decrease quality of life, many studies have investigated the effect of some natural and chemical substance on the length and quality of wound healing to find out beneficial interventions that rapidly and economically treat it. This review aimed to describe the physiology of cutaneous wound healing and some negative and positive factor with a focus on exercise. Methods: An electronic search without any time limitation was performed on the PubMed, Google scholar and web of science databases to find published articles in English. The keywords were wound healing, exercise, and physiology. According to relation to subject, similarities, and differences 48 articles were selected and reviewed. Results: wound healing is a complicated physiology process that consists of four consecutive overlapping stages. Disruption in each stage disturbs wound healing. Many chemical and herbal compounds are used to speed up wound recovery due to their anti-inflammatory property. Exercise is one of the effective factors in wound healing and many studies evaluated effect of different protocol of exercise on it. The results of studies show that aerobic exercise due to its anti-inflammatory and antioxidative effect is a beneficial method in shortening the length of wound healing, especially in aged, fat, and diabetic individuals. Conclusion: Moderate intensity aerobic exercise as a complementary medicine is a good intervention in the treatment of impaired and chronic wounds.

Purpose: The adequate use of sport-related modern knowledge such as new findings regarding nutritional and dietary supplements is an essential prerequisite of success in modern professional sport. Methods: In this semi-experimental study, 11 nationally prominent Taekwondoin with 8 to 12 years of experience and profile of (Age: 20±6 years, height: 178±12 cm, weight: 67±11kg, wrist circumference: 17±1 cm) were selected as subjects. The level of blood lactate, the time and speed of execution of Poomsae forms, and the number of Momdollyos successfully performed in 20 seconds were measured separately in a pre-test phase, after the intake of a placebo, and after the consumption of supplement drink. Results: Statistical results showed that lactate levels significantly increased compare to pre-tests in both groups. Although this increasing was not significant between groups in Momdollyo (p=0.599) and Poomsae (p=0.303). Indeed, number of successfully executed and also time of performance were significantly different in both Momdollyo (P=0.000) and    Poomsae (P=0.033). Conclusion: Intake of discussed customized decaffeinated supplement drink increased speed and number of execution of Poomsae forms and Momdollyo techniques but it seems that lactate levels depends on other factors in taekwondoin.

Background: Regular exercise has been shown to have a positive impact on both physical and mental health. There is growing evidence to suggest that exercise can improve mood, reduce symptoms of anxiety and depression, and increase overall well-being. Aim: This study aimed to investigate the role of ethical values and coaching styles in adherence to sports in group and individual athletes. Materials and Methods: The statistical population of the present study included 350 athletes in group and individual disciplines in Mashhad, 296 of them were randomly selected as a statistical sample. Descriptive and inferential statistics were used for statistical analysis in the present study, which was done using SPSS 23 (Chicago) and LISREL 8.80 software. Results: The results of the Kolmogorov-Smirnov test showed that the research data have a normal distribution. The analysis results showed a significant relationship between coaching style and its components with adherence to sport and between ethical values and its components with adherence to the sport. Also, the regression analysis results showed that ethical values and their components and coaching styles and their components have the ability to predict adherence to the sport. Conclusion: Finally, it was found that the structural equation model of the relationship between ethical values and adherence to sport and coaching styles and adherence to the sport has a significant fit. According to the results of the research, it can be said that coaches and those involved in sports can, by properly explaining and presenting ethical values, as well as the correct use and application of coaching styles, encourage people in the community at all levels and especially athletes to adhere to physical activity and exercise.