Journal of Sport and Exercise Physiology
Year:2016 | Volume:9 | Issue:1 |Papers Count:8

Purpose: The aim of this study was to investigate the effect of four weeks dynamic warm-up on static and dynamic balance and proprioceptive receptors in skilled female Gymnast.Methodology: For this purpose, 16 skilled female gymnasts (mean age9.62±1.45 years, height 130 ±15.62 cm, weight 28.24 ±8.52 kg and BMI 16.27±1.46kg/m2) were selected and divide into two groups [general warm-up (control), and dynamic stretching] randomly. The first protocol included a 10 minute jogging, and the second protocol consisted of jogging and dynamic stretching in muscles used in performing the skill. Subjects were tested before and after acute protocol and four weeks as the using different protocols. The indicators of the equilibrium of) anterior-posterior internal-external) in four static (with two legs, and with one leg) and dynamic situations (with two legs and one leg) by removing visual input were investigated. Balance assessed with dynamometer system equipped with 7 cameras and Kistler force plate. Statistical analysis of data was performed through ANOVA and the Bonferroni post hoc test at significance level of (p£0.05).Results: The results of this study showed, a significant increase in dynamic balance with both feet and a feet by removing visual input in a state of equilibrium with a dynamic warm-up protocol after four weeks (p=0.001 Also Static balance on two legs and one foot with a dynamic warm-up protocol was significantly increased after four week dynamic protocols respectively (p=0.001, p=0.005).Conclusion: Since the removal of visual inputs can lead to a dysfunction in the postural sway control, Use a dynamic warm-up exercises demonstrated in female gymnast that the fluctuations are significantly reduced compared to the control group in a way that improves there in the balance performance.

The aim of the present study was to assess differences in myostatin gene expression in slow and fast-twitch muscles of healthy male rats after 8 weeks high intensity interval training. Methods: For this purpose, 12 male Wistar rats divided into two groups, control (6=n) and trained (6=n). High intensity interval training was five days a week for eight weeks. Each session was formed from three intervals (four-minute with intensity of 90 to 100% VO2max and two- minute with intensity of 50 to 60% VO2max).24 hours after the last training session, the Extensor digitorum longus and soleus muscle were extracted and gene expression levels were measured by RT-PCR. Result: Statistical analysis using independent t-test showed that the soleus and EDL muscles myostatin levels decreased significantly in the experimental group compared with the control group (p=0.001). Conclusion: Hence it can be concluded that myostatin expression in both EDL and soleus muscle is reduced by high intensity interval training.

Purpose: The purpose of this study was to investigate the response of cortisol levels, TNF-a and plasma lactate to acute Q10 supplementation during constant load exercise in active females.Methods: 24 subjects were randomly assigned to supplementation and placebo groups. Supplement containing 2 mg per kg of body weight, coenzyme Q10, which was dissolved in 250 ml water. Placebo also contained water with food colour. Supplement and placebo consumed 120 min before the exercise test. Before and immediately after the test blood samples were collected. Data were analysed using the t test.Results: The results showed no significant differences between the rest and after exercise in the value of cortisol levels, TNF-a and lactate (p>0.05).Conclusion: According to the results of this study and not positive effects of this supplement on the lactate and immune system, it seems that there is no need for the use of this supplement in active people.

Background: The purpose of this study to verify the effects of resistance training on Serum BDNF Level and Memory Performance in Middle-aged Women with Metabolic Syndrome.Methodology: 22 volunteers middle-age woman with metabolic syndrome for sampling, were selected and randomly assigned to a resistance training protocol (n=12, 43.08 ± 5.14 years, 74.13 ± 7.16 kg) or a control group (n=10, 39.9 ±4.53 years, 82.23 ± 11.61 kg). In the resistance training protocol, ten exercises were performed, with 3 × 8–0 maximal repetitions three times per week (75%-80% 1RM) With regard to the principle of overload. Short term, midterm and long term memory tests and also blood sampling were conducted before and after training. Data were analyzed using independent and depended t-test, analysis of variance with repeated measures 2 × 2 with the level of statistical significance was set at P£0.05.Results: No significant changes in the levels of BDNF and midterm memory in the control and exercise and control groups was not observed (P³0.05). The dependent t test results showed a significant decrease in short term and long term memory in the exercise group (P£0.05), but after interactive exercise effect no significant changes was not observed (P³0.05).Conclusion: In spite of the fact the BDNF as a metatrophin, mediating the effects of exercise on cognitive function is known, but eight weeks of resistance training cannot have a favorable effect on increasing BDNF and memory function in middle-aged women with metabolic syndrome.

background and aim: physical activity is an important factor in improving the immune system and decreasing inflammatory agents, which can expand the growth by influencing anabolic and catabolic mediators. This study is being done with the purpose of determine inflammatory responses of children with idiopathic short stature to two weeks inactivity after the one period of physical activity.Materials and Methods: this semi-experimental study was conducted on the population of children attending to endocrine clinic of Atieh hospital of Tehran.14 idiopathic short stature children (4 girls, 10 boys) were randomly divided into control and experimental groups. Experimental group performed eight weeks, three sessions each week and each session 60 minutes. The intensity of physical activity was 40-60% of HRmax. IL-6, TNF-a and IL-1b were also measured before and after eight weeks of physical activity and after two weeks inactivity. Data were analyzed by kolmogorov-smirnov, independent t test and one-way ANOVA with repeated measures.Results: The result indicate that after eight weeks of physical activity, IL-6 increased insignificantly and IL-1b decreased insignificantly (p>0.05). Also, following two weeks of inactivity after eight weeks, inflammatory cytokines TNF-a, IL-1b decrease and IL-6 increase, but this changes were not significant (p>0.05). There was a significant difference between groups in the TNF-a (P=0.005) response after two weeks of inactivity.Conclusion: It seems that some positive effects of physical activity remain even after two weeks of inactivity. Therefore, in order to determine the required time for the inflammatory cytokines to be increased, researches with workout cycles longer than eight weeks are needed.

Aim: the purpose of this study was to investigate the acute effects of antagonist muscle PNF stretching on peak torque, rate of vertical jump height and fatigue of agonist muscle in knee joint of non-athlete subject.Method: fifteen physical education male students (21.7±1.3 yrs, 180.9±7.02 cm, 75.2±9.8 kg) volunteered to participate in current study. Subjects were tested for vertical jump height and isokinetic peak torque production during knee extension at 600.s and 3000.s and also tested for isokinetic 25 repetition peak torque production during knee extension at 600 for fatigue testing. Electromyographic data was recorded for the vastus lateralis and biceps femoris muscles during fatigue testing. Paired samples t-tests way used for analyzing data.Results: statistical results indicated that there was no significant differences between stretching groups and non-stretching groups in isokinetic peak torque production during Knee extension at 600.s-1 (257 vs 257 N.m; p=0.945) and 3000.s-1 (145 vs 146 N.m; p=0.754). And also no significant differences found between stretching groups and non-stretching groups in vertical jump height (54.3 vs 53.1 cm; p=0.358), also percentage of median frequency decrease of vastus lateralis muscle was not significant (14.3 vs 4.8 per; p=0.161) and work fatigue of agonist muscles (49.6 vs 49.8 pre; p=0.891).Conclusion: These results indicate that acute PNF stretching of antagonist muscles has no positive effects on peak torque, rate of vertical jump height and fatigue of agonist muscle. Therefore possibly using this method before exercise has no positive effects on increasing agonist muscles performance.

Introduction: The nutritional status of an athlete is a determinant factor for health, fitness and sports performance. The aim of this study was to investigate the nutritional knowledge, attitude and practice of male students' athletes in 2014, IR- university games.Methods: In this study, 330 student-athletes were selected by purposeful selection and were evaluated by descriptive-survey method. Data were collected by using the knowledge, attitude and practice questionnaire that comprised 4 sections. In section one, the personal information of subjects and in the three next sections, nutritional knowledge, attitude and practice were collected. The questionnaire consisted of 31 questions for nutritional knowledge, and 8 questions for nutritional attitude and to 21 questions for practice, which the maximum score for each question is one. Data analysis was carried out by using one sample t-test, one way ANOVA and Pearson’s correlation coefficient.Results: The results showed that nutritional knowledge and attitude for male students' athletes are low, but their nutritional practice was moderate. Also nutritional knowledge attitude and practice of men student athletes were lower than normal (p<0.05). There was a significant and positive correlations among knowledge, attitude and practice (p<0.05). However, there were no significant differences for nutritional knowledge, attitude and practice among on the subjects in different sports and academic levels (p>0.05).Conclusion: This study showed that the nutritional knowledge, attitude and practice of male students' athletes participated in the university games is low and that they need more theoretical and applied nutrition educations irrespective of their sport fields and academic levels.

Platelets play an important role in the etiology of cardiovascular disease. The aim of this study was to compare the effects of 8 weeks of high intensity interval training and continuous training on P-selectin expression and platelet indices in cardiovascular patients. Therefore, 30 CABG and PCI heart patient voluntary participated and divided into three groups (n=10): control, continuous and high-intensity interval group. Anthropometric characteristics and peak oxygen consumption was recorded before starting a workout. Each session was 40 minutes. Interval session consists of warm-up, 8 reps/ four min (exercise: 2min, active recovery: 2min, intensity: 90.30) and cool down, but continues session includes 30 minutes of continuous exercise intensity activity with 60% of peak oxygen consumption. The control group did not have a regular activity. Blood samples taken before and after the eight-week and their P-selectin (by flow cytometry) and platelet indices were measured. Repeated measure ANOVA with between group factor and multiple linear regression were used for statistical analysis. The results showed that P-selectin expression changes between the groups were significantly different (P=0.013). Post-hoc test show that the changes between control and interval groups were significant (P=0.011). But no significant changes were observed in all platelet indices (P>0.05).It is concluded that eight weeks of exercise leads to reduction in P-selectin expression that was also affected by type of activity. Based on more effects of interval training in cardiovascular patients, use of interval training can be suggested in their rehabilitation program.