Journal of Sport Biosciences
Year:2013 | Volume:5 | Issue:16|Papers Count:10

The aim of this study was to determine the effects of sodium bicarbonate supplementation on blood lactate level and anaerobic power of futsal players. 24 futsal players (mean age of 15.88±1.59 years, weight 62.02±12.76 kg, height 173.21±8.23 cm, BMI 20.51±3.33 kg/m2) were selected and randomly divided into two groups (experimental, N=12) and (control, N=12). The protocol consisted of a five-minute warm-up before Wingate test, 30 seconds on a Monark ergometer and then consumption of 3 mg/kg/bodyweight bicarbonate supplement or placebo for 70 to 120 minutes. Then, Wingate test was performed again to measure variables in the posttest. To determine blood lactate, a lactometer was used immediately after Wingate test. The comparison of differences and independent t test was used to analyze data. The results showed that the sodium bicarbonate supplement significantly increased anaerobic power of futsal players (p=0.008), but changes in blood lactate level (p=0.162), and fatigue index (p=0.560) were not significant. It can be stated that sodium bicarbonate supplement improved anaerobic power of futsal players, but it was not very useful for reducing fatigue resulted from lactate concentration.

Protein amyloid beta (Ab), as the pathologic hallmark of Alzheimer disease (AD), increases in the brain of diabetic patients. The aim of this study was to investigate the effect of 6 weeks of voluntary wheel running combined with allium paradoxum extract on cortex amyloid beta (Ab1-42) levels in diabetic rats induced with alloxan. For this purpose, 42 male wistar rats (weight 185+1 gr, 8 weeks old) were assigned randomly to 6 groups (n=7): normal control (c), training (T), control–diabetic (CD), diabetic–training (DT), diabetic–allium (DA), diabetic–allium–training (DAT). Subjects were diabetes through alloxan injection (120 mg/kg dissolved in saline) intraperitoneally. Training and diabetic–training rats inhabited in cages performed their training voluntarily on a running wheel for six weeks. At the end of the protocol, cortex Ab1-42 in T and DT groups decreased. Ab1-42 levels significantly decreased in T and DT compared with C and CD respectively (P<0.001). Also, Ab1-42 levels significantly increased in CD in comparison with C (P<0.001). Furthermore, voluntary training along with consumption of allium paradoxum extract decreased cortex Ab1-42 in DAT (P<0.001). Voluntary training and allium extract had positive effects on decreasing Ab1-42 levels; therefore, it can be recommended as therapeutic strategy for diabetes.

The aim of the present study was to examine the effect of one session of swimming and running exercise on the appetite and calorie intake in healthy girls. The research design was a cross–sectional one and 12 female university students (mean age 22.5±1.3 yr, weight 56.07±5.46 kg, body fat percent 27.125±8.316, BMI 21.175±2.68 kg/m2) voluntarily participated in three modes of control, swimming and running exercise with 80-85% maximum heart rate up to the exhaustion level. The appetite rate of the subjects was measured through the appetite questionnaire two hours before the exercise (in fasting mode), immediately after the exercise, two and eight hours after the exercise. Also, the calorie intake was recorded by the subjects themselves before, during and after the protocol. Data were analyzed using analysis of variance with repeated measures and one–way ANOVA. The test significance level was P£0.05. No significant change was observed in the appetite and calorie intake in one session of swimming and running exercise (P=0.05). One session of swimming and running exercise had no effect on the appetite and calorie intake. In conclusion, in contrast to what some believe, one session of exercise until eight hours after that did not increase appetite and can be used to control and reduce weight. Therefore, exercise can balance the calorie intake negatively. This negative balance will not recover shortly and there is no difference between swimming and running in this regard.

As the middle-aged in the society as well as stress-induced cognitive disorders and dementia are increasing, sport is identified as a suitable solution to prevent disorders in central nervous system. The aim of the present study was to compare the effects of 8 weeks of strength and endurance training on BDNF. For this purpose, 150 male wistar rats participated in endurance training (running with 10-25 m/min speed) and strength training (lifting the weight up the special ladder with 104-126% of body weight). Blood samples were collected at the beginning of the protocol, 24 hours after the last session of the 4th week and 24 hours, 3 and 5 days after the last session of the 8th week. Kolmogorov Smirnov test, multifactor analysis of variance and one-way ANOVA were used to compare the means and Pearson correlation coefficient was used to investigate the relationship between BDNF and cortisol. In the 4th and 8th weeks, BDNF increased significantly in strength training group (p=0.014 and p=0.047 respectively) but this increase was not significant in endurance training group (p>0.05). BDNF concentration significantly increased in endurance group compared with control group (p=0.032 and p=0.023 respectively). In the 8th week, three and five days after the last session, cortisol levels increased significantly in endurance group (p=0.046, p=0.02, p=0.044). There was no significant relationship between BDNF and cortisol during sample collection. It seems that intensity and duration of training influence BDNF levels. Moderate intensity training increased BDNF levels but high intensity training inhibited this increase for the reasons such as increased cortisol levels. Also, during training, strength training enhanced BDNF concentrations more than endurance training.

This study aimed at investigating the effect of BCAAs consumption on wrestlers' creatine kinase (CK) activity in a three-month depth jump exercise. For this purpose, 22 male wrestlers from Zanjan province (age 21.54±3.52 yr, weight 66.18±3.76 kg, height 168.36±2.41 cm, BMI 23.34±1.97 kg/m2) were randomly selected and divided into two groups. During the mentioned period, both groups had their breakfast at 7:00 AM, performed the depth jumps at 9:00 AM in six consecutive sets until exhaustion with 5-minute intervals and received their placebo and BCAAs by double-blind method after the jumps. Group one received 45 mg/kg of body weight of valine, leucine and isoleucine in a 4 ml/kg BW solution. Placebo group received 45 mg/kg of body weight of glucose in a 4 ml/kg BW salt and lime solution. Blood samples were gathered before (in fasting) and 48 hours after the depth jumps to measure CK activity. One-way analysis of variance and paired t test were used to investigate CK changes at (a=0.05). The results showed no significant difference in CK activity between the two groups (48 hours following the deep jump) in intergroup and intragroup investigations (p<0.05). Exhaustion may be the reason for cellular injury and plasma CK increase. It is suggested that subjects perform their activity after three months with the same workload to investigate CK.

The aim of this study was to investigate the effect of eight weeks of aerobic training along with milk supplement on GLUT4, glucose and insulin in overweight immature boys. For this purpose, 28 immature overweight boys (8 to 10 years) were selected according to the questionnaire of nutrition, exercise abilities, body mass index, health and welfare from volunteers. Then, subjects were divided into four groups randomly: training, milk, training+milk and control. The training protocol included 8 weeks of aerobic training at 45-60% MHR, 3 sessions a week. Milk supplement groups received 236 ml of milk daily. Before and after 8 weeks, blood samples (14 hours of fasting) were gathered to measure levels of GLUT4, glucose and insulin. Data were analyzed by factorial analysis of variance. The results showed that after 8 weeks the amount of GLUT4 significantly increased in training (p=0.001), training+milk (p=0.005) and milk (p=0.002) groups. But glucose and insulin decreased in training (p=0.058, p=0.001 respectively), training+milk (p=0.001, p=0.003 respectively) and milk (p=0.002, p=0.001 respectively); these changes were significant except for glucose in training group. It seems that a period of aerobic training along with milk consumption improves homeostasis glucose, decreases insulin and increases GLUT4 in overweight immature boys.

The aim of this study was to investigate the effect of different music rhythms on cardio respiratory responses during incremental exercises in young men. For this purpose, 17 non-athlete healthy males (ages: 19.76±0.97 yr, height: 176±6.72 cm, weight: 68.5±5.95 kg) voluntarily participated in this study. They performed Bruce protocol until exhaustion with no music, slow music and fast music conditions through counter balance format. All cardio respiratory indexes were measured in the 3rd, 6th and 9th time intervals. Each time interval was 72 hours. The results showed that listening to music (fast and slow) during incremental exercise significantly decreased perceived exertion (P=0.001) and respiratory rate per minute (P=0.0001) in the third stage, heart output, VO2, heart rate, ventilation per minute in all stages of test (P<0.05). But there was no significant change in Vo2max (P=0.764), maximum heart rate (P=0.478), stroke volume and tidal volume in all stages of the test (P<0.05). It can be concluded that music may influence perceived exertion in moderate intensity exercises. Probably, maximum levels of some cardiovascular variables are less influenced by music.

The aim of this research was to investigate the effect of 8 weeks of aerobic training and omega-3 fatty acid supplementation on plasma sICAM-1 in elderly men. In this study, 36 male non-athletes (aged between 50 and 70) were selected through available method and randomly divided into 4 groups (9 subjects per group): aerobic training+omega-3 supplement, aerobic training+placebo, omega-3 supplement and placebo. The training program included 8 weeks, 3 sessions per week, 30-45 minutes per session with 55-70% HRmax. Daily dosage of omega-3 fatty acid supplement was 2000 mg. Blood samples were collected after 14 hours of fasting before the study and 48 hours after the last training session. Data were analyzed with Kolmogorov Smirnov test, t test and one-way ANOVA at a£0.05. After 8 weeks of training, sICAM-1 insignificantly reduced in training+ omega-3 and omega-3 groups (p³0.05). Also, there was no significant difference among the groups after 8 weeks of training (p³0.05). It can be concluded that 8 weeks of aerobic training and omega-3 supplement had no significant effect on sICAM-1. It seems that significant changes in this new cardiovascular risk factor may depend on the duration and intensity of exercise and the amount of omega-3 supplementation that needs further research.