نشریه مطالعات کاربردی علوم زیستی در ورزش
پیاپی 5 (بهار و تابستان 1394)

During the last decades, the importance of amino acid supplementation has been recommended to improve exercise performance. The aim of this study was to investigate the effect of L-arginine supplementation on growth hormone, lactate and glucose responses to aerobic activity in boy students. Participants were included 10 athlete students with age: 18-16 years old. This research was a randomly semi experimental double-blind study which established in a basic and two supplementation (0.1 gr per kg/body weight) and placebo (Starch) situations. The subjects participated in three phases of aerobic activity (running at intensity of 15th Borg scale equal to 80-70percent of maximum heart rate for 30 minutes. The first phase was done before receiving of supplementation and placebo and the second and third phases were done after receiving three days supplementation and placebo. Blood samples were collected during the first phase before and after aerobic test, but in the second and third phases after receiving three days supplementation and placebo immediately after aerobic running. For extraction of results the ANOVA with repeated measures and paired t-test were applied and the significant level set as p<0.05. The result showed the significant increase in growth hormone after consuming supplementation with exercise (p=0.0001), but no significant change was observed for blood glucose (p=0.11) and blood lactate (p 0.09). Consumption (0.1 gr/ kg) of Arginine supplementation indicated significant effect on growth hormone response to aerobic exercise.; but it was not true for both lactate and glucose serum. Therefore, it can be suggested the higher doses and longer periods for consumption of this supplement.

Decreasing in physical activity, overweight and obesity are the main causes of increasing serum lipid profile. The interaction of these factors with each other and in response to exercise could be correlated with physiologic circadian functions. The aim of present study was to compare the effects of 8-weeks of general physical education course (1) at the morning and evening on aerobic capacity, body composition, blood lipids and lipoproteins among non-athlete students in Shahid Bahonar University of Kerman. 15 (evening group), 14 (morning group) and 15 (control group) subjects among non-athlete general physical education course (1) students were selected as volunteer sample. Fasting blood samples (12 to14 hours) were taken two times before and also after 8 weeks of intervention. The changes in serum lipids profile (TC, TG, lipoprotein HDL and LDL) were determined by enzymatic methods. The aerobic power and percent body fat were measured by Cooper test and skinfold technique respectively. The data was analyzed by a mixed two-way Split Plot ANOVA test (SPANOVA) and the significant level set as p≤0.05. The results indicated that 8 weeks of general physical education course (1) (one session in every week) had no significant effect on blood factors (TC, TG, HDL and LDL) and percent body fat (p>0.05). But, aerobic power of students regardless of time during the morning and evening were significantly increased (p<0.01). One session of general physical education course (1) would not be enough to improve student’s health, moreover there is no difference affect of performing these courses during the morning and the evening time.

The caffeine, as a psychoactive supplement, is widely used by the athletes, however the effectiveness of its consumption in different periods of training and sports was not understood. The purpose of present study was to determine the effect of caffeine consumption on some skill indicators and motor fitness in elite table tennis players of Sabzevar. Fourteen male elite table tennis players (mean age 29±11.6 years, height 175±7.79 cm and weight 77.07±15.26 kg) volunteered for the research. The study design was crossover, in which the subjects placed in 3 different conditions of control (Con), caffeine consumption [(C), 5 mg/kg], and placebo consumption (Starch powder as capsule), with a period of one day between the conditions. In each session, subjects performed forehand, backhand, and service techniques, and also agility and reaction time tests. The data were analyzed by the ANOVA repeated measures and Bonferoni post hoc tests and the level of statistical significance was set at p<0.05. The results showed that caffeine consumption had no significant effect on the physical fitness and skill indicators (p>0.05). Consumption of 5 mg/kg caffeine has no effect on improvement of skill indicators and motor fitness of elite table tennis players.

The purpose of this study was to identify the effects of ginseng supplementation and six weeks of resistance training on aerobic and anaerobic factors of non-active students at the university of Shahrood. In this way, 50 students of Shahrood university with an age average of 19±2 years and the body mass index average of 22±3 kg/m2 voluntarily participated in the study. The subjects were divided randomly into four groups including training+supplement (13 people), training+placebo (13 people), supplement (12 people), and control (12 people) groups. Training groups were performed a designed protocol three times per week for 6 weeks. Before and after the training program, the Bruce aerobic test, the Wingate anaerobic test and body composition were measured. The Kolmogorov-Smirnov test was used for evaluating of normal distribution of data and then the paired t-test and repeated measure ANOVA test (4×2) were applied for detection of significant differences (p<0.05) between groups. The peak anaerobic power (p=0.02) and maximum aerobic power (p=0.001) were significantly increased in the training groups, however, average aerobic power (p=0.12), minimum aerobic power (p=0.09) and fatigue index (p=0.32) did not show any significant differences between groups. Compared to the resistance training intervention, resistance training along with ginseng supplement may have a greater role in improving aerobic and anaerobic power in non-active male students.

Blood coagulation is one of the most important physiological factors in the body,s homeostasis imbalance. There are some conflicting data about the effect of exercise trainings, especially resistance training on this factor. Hence, the aim of the present study was to identify the effect of 12 sessions of resistance training on some coagulation and fibrinolytic factors in non-active men. Towenty subjects volounteered for this semi experimental study and randomly divided into two groups including experimental (n=10) and control (n=10) groups. The resistance training protocole included 6 movements such as chest press with halter, lat pull, triceps with halter, squat, extension and flexion of the knee which performed in 12 sessions up to 60-40 percent of one repetition maximum. Blood samples were obtained at baseline and at the end of the study. To make intra and inter-group comparisons, analysis of variance with repeated measures and LSD tests were appllied and for all statistical analysis, the significance level was set at p<0.05. The results showed that although the levels of fibrinogen reduced and the D-dimer increased after resistance training protocole, these changes were not statistically significant. Moreover, the number of platelets in both groups did not show a significant changes (p>0.05). As well as, prothrombin time and partial thromboplastin time factors increased significantly in resistance training group (p=0.02 and p=0.01 respectively). 12 sessions of resistance training via the reducing of levels of fibrinogen and increasing the prothrombin time and partial thromboplastin time could prevent thrombosis and sudden incidence of heart disease in non-active young men.

Postural stability is defined as body’s ability to maintain the center of gravity in the range of stability. Soccer players needs to have stable and reliable performance, therefore ankle injuries may cause an interruption in performance of professional soccer players. The aim of this study was to compare the postural stability of soccer players with and without chronic ankle instability during the jump-landing functional test. 28 soccer players include 14 people with chronic ankle instability (CAI) and 14 healthy people participated in study. Time to stabilization (TTS) and center of pressure (COP) of jump-landing functional test were measured by force plate device. Ankle injury was assessed by self reporting and also standard questionnaire. Independent sample t-test was used to analyze the collected data at significant level of p <0.05. The findings showed that there was significant difference in the COP of sagittal plane jump-landing in medial-lateral (p= 0.002) and anterior-posterior (p= 0.01) directions and it was the same for frontal plane jump-landing in media-lateral (p= 0.008) and anterior-posterior (p= 0.02) directions between players with and without chronic ankle injury. In other words, the COP in players with chronic ankle injury was significantly greater than healthy players, but TTS was very close to each other in two groups (p <0.05). In attention to the importance role of media-lateral ankle ligaments in postural stability, it seems that the injury of these ligaments could affect in COP displacement, and also postural stability factors. Soccer players with chronic ankle instability had more COP changes than healthy players. According to the role of proprioception in postural control, recommended that athletes with ankle injury contributed defects your stability and balance with practice proprioception training to increase the strength of the lower limb.

Although the cardiovascular risk factors are critical in obese women, it is possible to control related problems using by fiseable exercise training and nutrition strerategies. The aim of this study was to investigate the effects of 8 weeks aerobic exercise training along with green tea consumption on the some cardiovascular risk factors in obese women. Materialsand 46 healthy obese women voluntarily participated in this study and divided randomly into 4 groups including aerobic training (n=13), green tea (n=11), aerobic training+green tea (n=12) and control (n 10) groups. Aerobic training program included aerobic exercises up to 60 minutes at 55%- 65% maximum reserve heart rate, three sessions per week which lasted for 8 weeks. Green tea group brewed 2.5 g green tea in every meal during 8 weeks. Aerobic training+green tea group performed aerobic exercises along with green tea consumption but the control group received no intervention. Theblood samples were collected 48 h before and after 8 weeks of protocol in fasting status. The low density lipoprotein (LDL-C), high density lipoprotein (HDL-C), triglyceride (TG) and high sensitive C-reactive protein (hs-CRP) were measured using standard methods. To determine normal distribution of data, we used the Kolmogorov-Smirnovtest; then it is applied the one-way analysis of variance (ANOVA) and Scheffe tests in significant level of p<0.05. There were significant differences (p=0.0001) in hs-CRP variations between groups so that lesser value observed in the aerobic exercise+green tea group than green tea (p=0.001), aerobic training (p=0.03) and control (p=0.0001) groups. Also, it is observed significant differences in LDL-C variations between groups (p=0.009) so that its value had significant reduction in aerobic exercise+green tea (p=0.01) and aerobic exercise (p=0.03) groups than control group. On the other hand, the HDL-Cvariations was higher in the green tea group than control group (p=0.007), while there were no significantly differences between other groups. Moreover, although all experimental groups showed significant reduction (p=0.0001) in subcutaneous fat percentthan control group; there were no significantly differences (p=0.20) in TG between groups. Perform of aerobic exercise along with green tea consumption will induce more improvement in cardiovascular risk factors of obese women because of its antioxidant anti-inflammatory effects of this supplement.