SPORT PHYSIOLOGY (RESEARCH ON SPORT SCIENCE)
Year:2019 | Volume:11 | Issue:41|Papers Count:10

The aim of the present study was to investigate the effect of upper limb exhaustive activity on corticospinal excitability and motoneuron responsiveness of lower limb. Ten active males (Age 28. 1 ± 2. 99yr, Height 1. 77 ± 4. 1 cm, Weight 75. 7 ± 4. 98) volunteered to participate in this study and visited the laboratory on three different occasions. After measuring anthropometric features and familiarization with the pull up (exhaustive task) and magnetic and electrical stimulations in the session one, in the second and third visits, motor evoked potential (MEP), cervicomedullary motor evoked potential (CMEP) and maximum direct motor response (Mmax) were assessed immediately, 10 and 20 minutes after the termination of the exhaustive protocol ( perform pull ups until exhaustion, 7 sets with 1min rest intervals), by the use of magnetic stimulation over the motor cortex and spinal routes and electrical stimulation of peripheral nerve, respectively. The results showed that MEP in the Tibialis Anterior muscle (remote muscle) significantly decreased immediately (P₌ 0. 001) and 10 minutes (P₌ 0. 001) after performing the fatiguing task compared to the resting values. Also, no significant changes in CMEP and Mmax were observed in Tibialis Anterior muscle at any time points relative to the baseline (P= 0. 5, P= 0. 07). Based on the data obtained in this study, it looks that supraspinal centers account for the spreading of fatigue from the upper limb to the lower limb. Besides, such a supraspinal fatigue needs a considerable time to be recovered.

Fat metabolism disorders is a defect in pre-diabetic patients and a basis for type 2 diabetes. The aim of this study was to investigate the effect of 12 weeks continuous or high intensity interval training on fat burning capacity in pre-diabetic patients. 32 pre-diabetic patients (age: 38. 7 ± 4. 0 years; BMI: 26. 9 ± 1. 4 kg/m2; percent body fat: 26. 1 ± 2. 5%; VO2Peak: 2. 49 ± 0. 22 L. min-1) were divided into four groups: control (CON), high intensity interval training (HIT), continuous training at Fatmax intensity (FAT) and continuous training at anaerobic threshold (IAT). HIT, FAT and IAT groups participated in a 12-weeks training program with 4 sessions per week (with intensity of 90% VO2peak during the intervals, Fatmax intensity and/or anaerobic threshold intensity, respectively). Substrate oxidation, maximal fat oxidation (MFO) and Fatmax were determined during graded exercise test using the stoichiometric equations. Student’ s t-test and ANOVA were used to analyze the data. MFO was affected by training in HIT, FAT and IAT groups by 26%, 35% and 25%, respectively, which it was significantly different between FAT group and HIT and IAT groups (P ≤ 0. 05). In addition, the effect of exercise training on Fatmax in HIT, FAT and IAT groups was 26%, 25% and 35%, respectively, which it was significantly different between FAT and IAT groups (P ≤ 0. 05). Results showed that changes in fat oxidation rate was different in three groups compared to pre-training status. This means that the intensity and type of exercise may have effective role in fat oxidation metabolism in pre-diabetic patients.

The aim of this study was to determine the effect of upper body and lower body interval exercise on hemorheological factors. Twelve subjects (BMI=30± 3 kg/m2) participated in this study. After determining VO2max for upper body and lower body, subjects performed the interval exercise for upper body and lower body in two separate sessions with one week intervening. Interval exercise included 2 minutes of exercise at 85% of VO2max and 4 min recovery at 45% of VO2max. Blood sample were taken before and immediately after exercise and were analyzed. The results showed that irrespective of the exercise type, exercise resulted in significant increases in hematocrit, plasma viscosity, red blood cell count, lactate, rigidity index (Tk) and a significant decrease in the fibrinogen (P<0. 05) and no significant (P>0. 05) changes in the blood viscosity, red blood cell aggregation, red blood cell deformability, hemoglobin, oxygen supply to tissue, rigidity index Tk. The comparisons of the changes for all variables including blood viscosity, hematocrit, hemoglobin, oxygen supply to tissue, red blood cell aggregation, red deformability, and rigidity index (Tk), lactate, fibrinogen and systolic blood pressure did not show any significant differences between two exercise protocols (P>0. 05). However, changes of plasma viscosity in lower extremity and red blood cell count in upper extremity were significantly different between two trials (P<0. 05). It concluded that the acute exercise inducing changes in hemorheological variables, though, these changes are not related to exercise type and body parts involved in acute exercise.

The purpose of this study was to investigate the effect of endurance training and high fat diet on PGC-1a/FNDC5/Irisin pathway in Gastrocnemius muscle and visceral adipose tissue in male C57BL/6 mice. Male C57BL/6 mice were divided to 4 groups: High fat-Exercise (HF-E), High fat-Sedentary (HF-S), Low fat-Exercise (LF-E) and Low fat-Sedentary (LF-S). Exercise groups received exercise on a motor-driven treadmill at 21m/min, 45 min/day, 5 days/week for 8 weeks. 24 hours after final exercise session, mice were sacrificed and blood samples were taken from the mice to measure plasma irisin. Gastrocnemius skeletal muscle and visceral adipose tissue were excised and frozen in liquid nitrogen for assessment of PGC-1a and FNDC5 mRNA levels. Data was analyzed by a two-way ANOVA at P<0. 05. Data indicated that FNDC5 mRNA levels increased in muscle tissue of HFD groups vs LFD groups (P=0. 001). Interestingly, FNDC5 mRNA expression levels were significantly correlated with body fat mass (r=0. 8, P=0. 001). Also, data indicated that exercise and diet did not affect the plasma irisin level (P>0. 05). The results of this study indicate that high fat diet increases the expression of FNDC5 in the Gastrocnemius muscle tissue. Also, there is a potential correlation between the expression of muscular FNDC5 and body fat mass, which requires further studies to investigate its cellular and molecular mechanisms.

The aim of present study was to investigate the effect of endurance exercise training on some diabetic type 2 dependent variables in the form of meta-analysis of studies that were performed in Iran. In this research with the aim of finding related references Sid. ir and magiran. com databases as a statistical population has been searched from 1380 to 1395. All of the references in databases were founded in the electronic search, evaluated to finding other related references. The key words that we used were: Diabetes type 2 in combination with diabetes or endurance exercise or aerobic exercise or physical activity or Insulin resistance or lipid profile or fasting blood glucose and or HbA1c. Data analysis were done using STATA software version 12. 0 and P≤ 0. 05 was set as statistically significant. Generally, 85 articles were founded in primary search which after checking inclusion and exclusion criteria, 3 articles were included in this research. The results indicate that there were significant association between endurance exercise and blood glucose levels (P=0. 0001;-1. 396,-0. 423; 95% CI), insulin (P=0. 0001,-1. 479,-0. 469; 95% CI), insulin resistance (P=0. 0001;-1. 605,-0. 591; 95% CI), HbA1c (P=0. 001;-1. 334,-0. 369; 95% CI), LDL-c (P=0. 007;-1. 111,-0. 172; 95% CI), HDL-c (P=0. 0001;-1. 605,-0. 591; 95% CI), triglyceride (P=0. 018;-1. 030,-0. 097; 95% CI) and cholesterol (P=0. 002;-1. 229,-0. 281; 95% CI). Generally, this systematic review and meta-analysis study was demonstrated endurance exercise could be related with decrease diabetes type 2 related risk factors. So, it is recommended that sport and medicine experts use endurance exercise as a nonpharmacological intervention for treatment of diabetes type 2 patients.

The aim of this study was to investigate the effect of aerobic interval training on acylated ghrelin, peptide tyrosine tyrosine (PYY) and glucagon-like peptide-1 (GLP-1) in healthy young men. Twenty male students with age 22. 26± 1. 25 years old and BMI 23. 2± 1. 4 kg/m2 were randomly assigned to the training and control groups. The training group completed a high intensity interval aerobic exercise training for 12 weeks. The training program consists of four minutes running periods on treadmill with intensity of 85-95%HRmax followed by three minutes of 65-75% HRmax rest active periods. The levels of plasma acylated ghrelin, PYY3-36 and GLP-1 were measured by ELISA method before and after eightand 12-weeks trainings. In data analysis, was used the Mann-Whitney U test in order to compare the control and training groups and the Wilcoxon test in order to compare the training periods. The results showed that in the training group, levels of acylated ghrelin significantly (P=0. 008) decreased after 12 weeks compared to the eight weeks. However, there were no significant changes in the acylated ghrelin, PYY and GLP-1 levels compared to the control group after eight and 12 weeks. Overall it seems appetite hormones alterations in young active males in response to aerobic interval trainings were not considerable, but a 12 weeks period of aerobic interval training may decrease appetite compared to the same training during eight weeks.

The purpose of this study was to investigation of hemostasis system responses to entertainment open-sea air dive in depths of 9 and 18 meters. Twenty men diver with a mean age of 24. 5 ± 3. 2 years voluntarily participated in this study. In each diving session, 10 participants dive in depth of 9 meters and 10 others dive in depth of 18 meters, that their selection was randomly and they were changes together in the next session. Diving lasted for 30 minutes. Blood samples were taken immediately before and after the diving. To data analysis, t test was used. The results indicated that mean platelet count, PT and aPTT were reduced followed by diving in both depths of 9 and 18 meters (P ≥ 0. 05). However, fibrinogen levels were increased after diving at both 9 m and 18 m depth and tissue plasminogen activator (tPA) activity only at 18 m depth compared to the baseline (P >0. 01). Also, after diving at the depth of 18 m, platelet count and PT were lower (P ≤ 0. 05), and fibrinogen and tPA activity were higher than diving at 9 m depth (P < 0. 01). It seems that open-sea air diving can disrupt hemostasis system, especially blood clotting system. In addition, diving depth and height of the decompression effect hemostatic responses.

The study aimed to investigate the acute and chronic effects of endurance training on calcitonin gene-related peptide (CGRP) in the brain, cerebrospinal fluid (CSF), and serum in male Wistar rats. Frothy animals were equally divided into four groups including control, acute, trained chronic, and trained acute. The acute group performed only one endurance exercise session, trained acute performed a single exercise session following a twelve-week endurance training, and trained chronic performed twelve-week of endurance training. CSF was collected from the cisterna magena and various parts of the brain were extracted. CSF and serum concentration of CGRP and its gene expression were measured by ELISA and Real Time-PCR technique, respectively. Statistical test of One-way ANOVA was used for data analysis. Compared with control group, CGRP concentration in CSF (acute: P=0. 006; trained acute: P=0. 008) and serum (acute: P=0. 009; trained acute: P=0. 007) increased significantly. CGRP gene expression increased only in the cortex of the acute (P = 0. 007) and trained acute (P = 0. 006) in comparison to control group; Compared with the acute group, CGRP gene expression increased in the cortex of the trained acute group (P = 0. 018). The chronic effect of exercise did not appear in any of research variables in trained chronic group. In conclusion, CGRP increment in CSF and serum during endurance exercise is likely due to its enhanced expression in the cortex. In addition, resting values of CSF and serum CGRP are not affected by long-term endurance exercise; however, they are subjected to exercise response to adaptation.

The lack of a futsal specific test to evaluate the performance (aerobic and anaerobic) of futsal players is quite evident. The purpose of this study was to design and measure the validity and reliability of a specific performance evaluation test for futsal players. 84 male students who members of the university futsal team volunteered to participate in this study (age: 22 ± 2. 04 years, BMI: 22. 3± 2. 06 kg/m2). To design the test, the most important futsal techniques and drills were identified based on scientific literature, opinions of coaches, and conditioning and exercise physiology experts. In the end, dribbling, passing, shooting, ball control, jumping, speed running, backward and sideways running were selected, so that the movement pattern was similar to a real futsal game. Then, these selected skills and drills were designed in a tandem and along the route. To categorize the players and evaluate their performance, three coaches were asked to score the subjects from 0 to 100 in three different official games. In order to predict the performance by using each item of the test and total score of the test, multiple and simple regression equations were used, respectively. Validity and reliability of the test were calculated by the use of Spearman correlation coefficient and ICC, respectively. The results showed that there is a negative and significant correlation between coaches scores and the test record (r=0. 91, P<0. 05). Also, multiple linear regression equation showed that almost all tests drills are valid predictors of final record. Test-retest reliability showed high stability between result of the test. In conclusion, the new test has a high validity and reliability to evaluate the performance of futsal players and can be used by coaches and teachers.

In pathological conditions, FSTL-1, NDNF and VEGF proteins have a key regulatory role in function of the cardiovascular system. Relative to the role of these factors with exercise, research is limited. Therefore, the purpose of this study was to investigate the effect of 6 weeks of endurance training on FSTL-1, NDNF, VEGF and vascular changes in heart muscle of male rats. Methods: 10 male Wistar rats were randomly divided into 2 groups (n = 5): healthy control and exercise training. Endurance training was performed for 6 weeks, 5 days a week, 30 minutes each session, and moderate intensity (65-55% VO2max). 48 hours after the last training session, the rats were anesthetized and their heart tissue removed. ELISA method was used to measure FSTL-1, NDNF and VEGF values and staining (H&E) was used to considering of vascular changes in heart tissue. Independent t-test and Pearson correlation test were used for data analysis (P <0. 05). Results: 6-week endurance training significantly increased the FSTL-1 values (P = 0. 002) and NDNF significantly decreased (P = 0. 001). The diameter of the vessels in the exercise training group decreased significantly (P = 0. 073). Conclusion: 6 weeks of endurance training increases the amount of FSTL-1 in the heart muscle, which it seems that very effective in preventing cardiovascular disease. Considering the results of VEGF and vascular histology, the physiological effects of NDNF on the induction of cardiac angiogenesis in healthy subjects with exercise training need further studies.