PHYSIOLOGY OF SPORT AND PHYSICAL ACTIVITY
Year:2018 | Volume:11 | Issue:1|Papers Count:12

Purpose: The purpose of this study was to determine the effect of high intensity interval training in temperate and warm environment on serum BDNF in healthy men. Methods: In this research, 24 healthy male students according to vVo2max estimation divided to 3 groups, training in the warm environment (n=8), training in the temperate environment (n=8) and control (n=8) categorized as matched. Subjects of experimental group were trained 12 sessions for two weeks. Each session included 5 set of 150 seconds running on treadmill with %85-90 of vVo2max with 150 seconds active recovery between each set with 50 percent of vVo2max. Serum BDNF was assessed using ELISA kits and the data were analyzed by one-way ANOVA. Results: The results show that one session high intensity interval activity in warm (p=0. 018) and temperate (p=0. 045) environment induce significant increment in serum BDNF, However between training group, significant difference was not observed (p=0. 262). Furthermore two weeks of high intensity interval training in warm (p=0. 001) and temperate (p=0. 012) environment resulted in significant increment in serum BDNF, also two weeks of training on the level of BDNF not produce significant difference between training and control groups (p=0. 267). Conclusions: It seems that high intensity interval training regardless of whether in temperate or warm environment increases the level of BDNF.

Purpose: Iron plays an important role in oxygen transfer, mitochondrial respiratory chain enzymes, and oxidative phosphorylation; therefore, the reduction of iron can have a negative effect on the oxidative performance of athletes. The aim of study was investigate the effect of endurance exercise programs and iron supplementation on some cellular respiration factors in rats. Methods: Forty male wistar-rats were divided into four groups. experimental Group I, do endurance exercise programs on treadmill in during 12 weeks (intensity 32 m. min-1, 60 minutes in every session, and 5 sessions in a week) (T). Experimental group II do same exercise program, but intake daily 800 micrograms iron supplementary (Ferrous-Sulphate) (Ti). The control group C was without exercise (sedentary) (S), and experimental group III, did not do any exercise, but received an 800 microgram daily iron supplement (Si). After 12 weeks, their blood and muscle tissue samples were analyses. Data were analyzed using one way-ANOVA and Kruskal-Wallis Test (P<0. 05). Results: Blood ferritin concentration only in the experimental group I and absolute weight of soleus muscle and cytochrome C oxidase only in the experimental group II than other groups was statistically significant (p<0. 05). Also, muscle hypertrophy, capillary density, and mitochondrial density in the experimental groups I and II compared with the control group and experimental group III were significantly different (p<0. 05); But, this differences between both experimental groups I and II were not significant. Despite, body mass, relative weight of soleus muscle, and maximum oxygen consumption in the Experimental groups compared with the control group were significantly different and these differences between the experimental groups also were significant (p<0. 05). Conclusions: It seems that iron supplementations combined with exercises maybe improve some markers of cellular respiration, hypertrophy, and aerobic capacity; Despite, these improvements probably do not occur in detraining.

Purpose: The aim of this study was to investigate the effect of eight weeks of respiratory muscle training (RMT) with two different protocols on performance and ventilatory factors in soccer players. Methods: Thirty young trained soccer players between 16-19 years of age were randomly divided into 3 groups: experimental A (n=10), experimental B (n=10) and control (n=10). All groups carried out their regular soccer training with a 8-week RMT period of 1×30 breaths twice daily, five days weekly at 55% (experimental A) or 15% (control) maximal inspiratory pressure (MIP) or 1×50 breaths twice daily, five days weekly at 40% MIP (experimental B). MIP; standard spirometry; Yo-Yo intermittent recovery test level 1 (YYIRT level 1); Repeated High-Intensity Endurance Test (RHIET) and Running-based Anaerobic Test (RAST) were measured before and after the period. One-way ANOVA was used to analyze the data. Results: MIP, VO2max, running distance, and repeated sprint ability (RSA) increased significantly and rating of perceived exertion (RPE), rating of perceived breathlessness (RPB) and blood lactate concentration decreased significantly in EXP1 and EXP2 groups compared to Control group (p<0. 05) but there was no significant difference in ventilatory volumes (VC, FVC, FEV1. 0, MVV, and PEF) among groups (p>0. 05). Conclusions: The results showed that RMT is a good complement to enhance performance in soccer players and should be included in their physical fitness training.

Purpose: Exercise can lead to various hematological changes and it may be effects on some blood variables. The purpose of present study was to investigate the effects of resistance training with different order on hematological changes (include HGB, HCT, RBC, WBC, MCV, MCH, MCHC, RDW, PLT and MPV) in overweight women (BMI= 25-30 Kg/m2). Methods: Thirty-one overweight students (Weight: 71. 91 ± 8. 28 kg and Height: 160 ± 0. 05 cm) were objectively selected and randomly divided into three groups: the experimental group 1 (perform exercises from large to small muscles, n= 10), the experimental group 2 (perform exercises from small to large muscles, n= 11) and the control group (without any training program, n= 10). Resistance training consists of 6 weeks (3 sessions per week). The hematological variables were measured in resting conditions before experiment and again after completion of the training period. Results: Findings using by one-way ANOVA revealed there were no significant differences in any of the hematologic variables levels between three groups. Conclusion: In general, results showed that medium-term resistance training program and so changing the sequence of performance of resistance exercise – none of them – do not have any effect on hematologic responses.

Purpose: The present study was designed to determine the metabolic responses to hyperglycaemia during exercise in elderly men. Methods: Eight healthy males (Age, 63. 3± 5. 2 years) voluntarily participated and reported to the physiology laboratory on two separate occasions. With one week intervening subjects performed 40 min exercise on a cycle ergometer at 60% VO2max after 30 minutes of ‘ prime’ glucose or placebo infusion. Respiratory gases were undertaken throughout the exercise and four blood samples were taken before infusion, after 30 min infusion, after 20 min exercise and immediately after exercise. Blood samples were analyzed to determine insulin, NEFA, glycerol, 3-OHB and HOMA Scores. Fat and carbohydrate oxidation were calculated by using respiratory gases of O2 and CO2. Results: Insulin and glucose concentrations were significantly (p<0. 05) higher, and NEFA and glycerol were lower during exercise after glucose infusion. However, 3-OHB, fat and carbohydrate oxidations were not significantly different between two trials (p>0. 05). Conclusions: Based on the findings of the present study it could be concluded that in elderly men the maintenance of blood glucose during exercise through glucose infusion affects on lipolysis and metabolic factors, but has no effect on muscular fat and carbohydrate oxidation.

Purpose: The purpose of this study was to investigate the effect of aerobic exercise and black carbon particles on gene expression of NF-κ B and TNF-α in rats. Methods: Twenty-four male Wistar rats with an average body mass 279. 29± 26. 97 g were randomly divided into 4 groups A: without exposure PM10 and aerobic exercise, B: aerobic training, C: exposure to PM10 carbon black (5 mg/m3; per rat), D: and aerobic exercise concomitantly with exposure to PM10 carbon black. Twenty-four hours after the last training session and exposure, the animals were sacrificed. Real time-Pcr technique was used. Two-way ANOVA and post hoc LSD was used to determine the significance of differences between groups. Results: There was significant difference between groups A and B (P=0. 001) and B and D (P=0. 003) in the amount of TNF-α . Significant difference between A and B groups (P=0. 008) in the amount of NF-κ B was observed. Conclusions: four weeks of aerobic exercise and PM10 exposure lead to modify the inflammatory factors of NF-κ B and TNF-α . It seems that these changes lead to reducing the risk of neurodegenerative diseases.

Purpose: The aim of this study was to compare the effect of two types of body-weight and suspension resistance training on general soccer ability skills of children. Methods: Thus, 30 children (mean age 12. 3 ± 0. 55 yrs. ) without the history of resistance training were randomly divided into three suspended resistance training, unsuspended resistance training and control groups (n=10 in each group). These children have been participated in regular and identical soccer training three days per week during the investigation. All subjects in the three groups carried out the Mor-Christian soccer skill test before and 48 hours post training periods. The eight week of resistance training on suspended and unsuspended surfaces were designed progressively according to ACSM recommendations for children. Suspension training was conducted using TRX bands and unsuspension training using body weight. Comparison between groups were conducted using one-way analysis of variance (Using delta method). Results: The result of study indicated that soccer skills in Mor-Christian test increased significantly in TRX group compared with body-weight training group (P˂ 0. 05). Conclusions: Thus, according to the low risk, low cost, and fun of TRX, and due to the results of this study, this type of resistance training could be recruited in children population to develop their general soccer ability skills more efficiently than traditional body-weight training.

Purpose: high intensity interval training (HIIT) can damage liver. can green tea extract, as an antioxidant, reduce this liver damage? The aim of this study was to investigate the effects of green tea supplementation on two enzymes ALT and AST as indices of liver damage after high-intensity interval training on professional soccer players. Methods: Sixteen soccer players were divided into two groups in a quasi-experimental design with repeated measurements. Test on two occasions, and in each Blood, samples were collected 5 minutes before and 24 hours after performing the test. The training program included running with high intensity and 2 min rest between each activity. After 14 days, Conditions was repeated with the exception that a placebo group consumed green tea supplement in this stage. The data were analyzed using paired t-test to determine differences between groups. Results: The statistical results showed, AST enzyme in supplement group immediately and 24 hours after exercise was significantly lower than the placebo group (respectively (p=0. 001) and (p=0. 02)). ALT enzyme also in supplement group immediately after exercise had a much lower dose compared with the placebo group (p=0. 012) but ALT enzyme no significant difference was observed 24 hours after the activity. Conclusions: Based on the significance of the results it seems that green tea extract would reduce the indices of liver damage after high intensity interval training.

Purpose: Paralympic games festival are the most important competitions for disabled people in the world that is held regularly every four years. Competing in sport tournaments and having high performance in tourney needs different schemes such as good nutrition. So the purpose of this study was to assess the macronutrients intake status and energy expenditure of elite Paralympic athletes in Tabriz. Methods: thirty five elite Paralympic athletes in Tabriz (24 men and 11 women: BMI: 25. 8 and 22. 9 kg. m− 2, Body fat percentage: 22. 6 and 28. 7%, WHR: 0. 96 and 0. 85) filled consent and general information forms. Three-day self-reported food diaries and energy expenditure were analyzed. Macronutrients, fiber and calorie intake were calculated in Nutrition IV software. Energy expenditure and calorie of food intake in various meals were analyzed too. Descriptive statistic was used for analyzing data. Results: Mean amount of calorie intake and daily energy expenditure in men and women was (3573. 7, 3179. 2 in men and 2191. 7, 2165. 6 Kcal per day in women). Energy distribution in descending feature was in breakfast, lunch, dinner and snacks in men. It was in lunch, dinner, breakfast and snacks in women. Intake of macronutrients in elite Paralympic and fat intake in elite Paralympic was higher than reference values. Fiber intake in men athletes was lower than reference values but it was higher than reference values in women. In general, the calorie intake and energy expenditure in women were more favorable than men. Conclusions: The amount of macronutrients intake status in elite Paralympic men and fat intake in elite Paralympic women was more than reference values. Therefore, diet monitoring of Paralympic athletes seems necessary.

Purpose: In the present study, the effect of eight weeks of interval hypoxic training (respiratory control method) on the serum level of Brain-derived neurotrophic factor (BDNF) in active women was envestigated. Methods: Fourteen active women were randomly assigned to either the control (n=7) or experimental (n=7) group. The women in the control group performed running interval training under normoxi condition and the subjects in the experimental group performed runnig interval under hypoxic condition for eight weeks. At the beginning of the survey and 24 hours after the last training session of the eighth week, the blood samples of both groups were collected to determine serum Brain-derived neurotrophic factor level. Kolmogorov-Smirnov and Leven's test were used to determine normal distribution of data and homogeneity variation of groups, respectively. For data analysis, statistical methods including paired and independent-samples t-test at a significance level (p≤ 0. 05) were used. Results: The results showed a significant increase in serum levels of Brain-derived neurotrophic factor after eight-week interval hypoxic training compared to the interval training. In this regard, the study of betweengroups’ differences showed that there is significant difference between post-test phase of control and experimental groups (P≤ 0. 036). While, the study of withingroups’ differences showed that there was no significant difference between pre and post-test phase in control group after eight-week interval training (P=0. 157). The difference was significant in experimental group (P≤ 0. 011). Conclusions: The results of the present study suggest interval hypoxic training has an additive effect in the levels of Brain-derived neurotrophic factor in active women. Thus, it is a good substitution for training at altitude and blood flow restriction training in terms of time of performing physical activity, cost and implementation. Therefore, combining sport training with hypoxic and obtaining the desired results in shorter time seems to be an appropriate strategy.

Purpose: The aim of this study was to survey of the relationship between heart rate deflection point (HRDP) by the short distance maximum (S. Dmax) and second ventilatory threshold (VT2). Methods: Twenty-one sedentary men volunteers (mean age 19. 9± 1. 31 years; height 173. 4± 5. 3 cm; weight 67. 9± 8. 9 kg; maximum oxygen uptake 3. 08± 0. 52 L. min-1) performed an incremental treadmill exercise test to exhaustion. To determine the HRDP, each subject heart rate was recorded by using a polar monitor and analyzed by a designed computer program. Respiratory gases during the exercise test was measured with a gas analyzing system. Data were analyzed using depended t-test, Bland and Altman plots and intraclass correlation coefficient. Results: The HRDP was noticed in all subjects. No significant difference (p > 0. 05) between the heart rate, oxygen uptake, ventilation, tidal volume and respiratory rate corresponding to HRDP and VT2. Also, results of ICC and Bland-Altman plots showed a good agreement between HR and VO2 measured at the HRDP and VT2. Conclusions: It could be concluded that S. Dmax method is an accurate and reliable alternative to the expensive and time-consuming invasive methods. Therefore, the S. Dmax method can be used for the determination of anaerobic threshold in healthy young men.

Purpose: The aim of this study was to compare the effect of eight weeks aerobic and resistance training on oxidant, antioxidant status and lipid profile in obese girls Methods: Thirty obese girls (age 30± 5years, height 1. 60± 2m, weight 85. 23± 6. 7kg, Body mass index 31-33kg/m2) were divided randomly into three aerobic exercise, resistance and control groups. Experimental groups of aerobic exercise performed on a treadmill by 60 to 75% of heart rate reserve and intensity resistance training 55 to 75% 1RM for 8 weeks. Blood samples of the subjects before and after 48 hours of training and 12 hours of fasting protocols were collected. Data analysis using ANOVA and Tukey post hoc test was conducted at P≤ 0. 05. Results: Aerobic training significantly reduced the level of malondialdehyde and significantly increased superoxide dismutase and total antioxidant capacity of plasma in obese girls (P≤ 0. 05). However, there was no difference between the effect of eight weeks aerobic and resistance training in plasma nitric oxide, in obese girls (P=0. 069). Conclusions: It seems aerobic training can make significant changes in the body oxidative and anti-oxidative and adjusting lipid profile, reduce risk of cardiovascular disease in people with obesity.