فصلنامه فیزیولوژی ورزشی
پیاپی 43 (پاییز 1398)

Platelets play an important role in formation of a stable hemostatic white thrombus and a major role in the blood-clotting process. It has also been suggested that platelets are important in many of the reactions in the intrinsic pathway of coagulation. Recent evidence emphasizes the pivotal role of abnormal platelet function in acute coronary artery diseases, myocardial infarction, unstable angina and stroke. Acute exercise might be harmful for inactive individuals and particularly patients, if the exercise intensity is high. One of the main mechanisms causing this, is exercise-induced thrombosis. On the other hand, regular exercise or exercise training results in health benefits and improvements in lifestyle not only in normal healthy subjects but also in patients. However, the study of exercise training effects on blood platelets are highly contentious because of the fact that the analytical methods employed to study platelets are different and accompanied by numerous methodological problems. Few studies are available on the effect of training on blood platelets and the exact effects of exercise training on platelet activation and function is not as yet known. This lack of information makes further studies particularly important, in order to clarify whether there are favorable effects of exercise training on platelet aggregation and function in health and disease. This article presents a summary of the previous research findings that investigated the interaction between acute and chronic exercise and platelets in health and disease, as well as providing directions for future studies.

In diabetic patients, cardiomyopathy leads to the development of left ventricular hypertrophy, increased cardiac hypersensitivity to ischemic injury, and heart failure. Following the onset of diabetes-induced inflammation, Toll-Like Receptor4 (TLR4) is activated. Protective factors, including the Activated Transcription Factor 3(ATF3), are activated by hearth in response to such inflammation. Exercise, especially High Intensity Interval Training, reduces the effects of diabetic cardiomyopathy through reducing inflammatory factors. This study aimed to determine the effect of High Intensity Interval Training on TLR4 and ATF3 gene expression in cardiac muscle of male diabetic rats. A total of 48 Rats (6 weeks old) weighing 150 g were randomly divided into four groups of 12 consist of: Control group(C), Diabetes group (D), Diabetes –High Intensity Interval Training (DIT) and High intensity Interval Training (HIIT) groups. Six weeks of High Intensity Interval Training included 10 repetitions of 1-minute running on a treadmill with 2 minutes of rest between sets, 3 days a week. Gene expression was performed using the Real-Time PCR technique and the calculation of the changes using the 2-ΔΔCT method. The data were analyzed by Fisher and M-ANOVA tests at a significant level of P ≤ 0.01. The findings of the present study showed a significant increase in the expression of Activated Transcription Factor-3 gene and a significant decrease in the expression of Toll like Receptor-4 gene. As a result, High Intensity Interval training by activating the pathway and different molecular cell mechanisms dramatically reduced the negative effects of diabetic cardiomyopathy.

The aim of this study was to determine the effect of six weeks high intensity interval training (HIIT) with turmeric supplementation on visceral fat, subcutaneous abdominal fat and insulin resistance in obese females. Thirty obese women aged 20-25 years in quasi-experimental study with pre-post testing design, were selected purposefully and were randomly divided into two homogeneous groups of 15 participants: HIIT & placebo, and HIIT & Turmeric supplement (3 milligram curcumin per kilogram body weight per day). Preparation period performed for 3 weeks and HIIT performed for 6 weeks and 4 sessions per week. Blood samples were taken in two phases, before and 48 hours after last exercise session in the follicular phase. Abdominal fat was measured by ultrasound system. Serum insulin and glucose were measured by enzyme immunoassay and photometric method respectively. The data were analyzed at α

The Physical activity and exercise training are among the factors that reduce the complications of diabetes including diabetic neuropathy pain. The purpose of this study was to investigate the effect of six weeks endurance training with the same volume on the glial cell-derived neurotrophic factor (GDNF), nuclear factor- K</sub>B (NF-K</sub>B), and pain in sensoty roots of spinal cord in rats with diabetic neuropathy. The study sample was 40 Wistar rats (10-week-old and weighing 230-260 g). Ten rats were assigned in healthy control group and 30 other rats were diabetic by interperitoneally injection of Sterptozotocin (45 mg/kg, dissolved in citrate buffer, pH=4.5). After creating diabetic neuropathy, rats were randomly assigned to three groups: diabetic one-time training, diabetic two-times training, and diabetic control. Both training protocols were a six weeks aerobic training with 60- 70% VO2max on the treadmill. 48 h after the last training session, the sensory part of spinal cord sampled. Data were analyzed with one-way analysis of variance, Scheffe, Kruskal- Wallis, and Mann- Witney U tests (P<0.05). Results showed; GDNF levels did not have a significant difference between one-time (P = 0.146) and two-times (P = 0.131) training with the neuropathic control group. Also, there was no significant difference in the mean GDNF level between one-time and two-times training groups (P = 0.990). The mean NF-K</sub>B level in the one-time training (P = 0.022) and two-times training (P = 0.039) groups was significantly lower than the neuropathy control group, but there was no significant difference between the mean NF-K</sub>B level in one-time training and two-times training groups (P = 0.994). The results of pain behavioral tests showed that six weeks of one-time and two-times training significantly reduced neuropathic pain (P = 0.001), while there was no significant difference between the one-time and two-times training groups (P = 0.990). It seems, both one-time and two-times endurance training have a positive effect on NF-K</sub>B levels and pain, and reduce the complications of diabetic neuropathy, while not affecting GDNF levels.

Aging is a period that in addition to physical disturbances is associated with behavioral, cognitive and motor disorders, and endurance exercise can improve these disorders by increasing expression in some factors. The aim of this study was to investigate the effect of 12 weeks endurance running on treadmill (5 days a week, 20 m/min) on gene expression of PGC-1α, BDNF, learning and memory in the hippocampus of elderly rats. The rats were randomly divided into three groups: aging, aging- training and young. After the end of the protocol, hippocampus was excised and was frozen at -80 °C for mRNA condensation. Gene expression was compared by one-way ANOVA and Morrise Water Maze test was analyzed through repeated measure ANOVA. The findings show that the learning and spatial memory decrease in aging group compression with young group and training improved this disorder. Also, training led to an increase in expression of PGC-1α and BDNF in the aging group, so there was no significant difference in expression of these two factors between the aging-exercise and young group (P˂0.05). Therefore, considering the role of PGC-1α and BDNF in protection of neurons, it seems that endurance training has a protective effect on aging disorders.

Understanding health-related fitness status, especially body composition and cardio-respiratory fitness indicators is an important factor in determining individual health. The purpose of this study was to developing and updating the physical fitness norm for men aged 18-60 years old of Tehran province. In this descriptive cross-sectional study, 250 men aged 18-60 years old with a mean age of 31.28 ± 9.39 years, height 176.65 ± 6.64 cm, weight 83.00 ± 13.30 kg from different regions of Tehran were recruited by cluster and random sampling and divided into different age classes. In this study, body mass index (BMI), waist to hip ratio (WHR), body fat percentage (caliper), cardio-respiratory fitness (Rockport 1mile walking/Running), Flexibility (sit & Reach), endurance of abdominal muscles (curl up), Endurance of shoulder girdle muscles (modified push up) and strength of hands (hand grip) measured in subjects. Descriptive statistics, z equation and percentage points were used to prepare the relevant norms. The findings of this study showed that the mean cardio respiratory fitness (45.78 ± 10.42 ml / kg.min-1), body fat percentage (27.45 ± 7.41), BMI (26.54 ± 3.63 kg) Flexibility (27.43 ± 10.49 cm), endurance of abdominal muscles (33.36 ± 11.62), WHR (0.86 ± 0.57), Endurance of shoulder girdle muscles (24.71 ± 15.15), strength of hand muscles (45.18 ± 7.79 kg). The results of this study can be used as a reference for health and clinical studies in different age groups.

The purpose of this study was to investigate the effect of 6 weeks progressive aerobic training with tail injection of adipose tissue-derived stem cells on nerve growth factor (NGF and vascular endothelial growth factor (VEGF(levels in streptozotocin-Induced diabetic rat’s hippocampus. 48 rats (weight: 220-240 g and age: 9 week) were divided into 6 groups: control, sham ،control diabetes, diabetes+exercise, diabetes + stem cell, diabetes + exercise + stem cell. The exercise protocol was treadmill running for 5 days per week with intensity of 60-70% VO2max for 6 weeks. In the stem cell receiver group, Insulin Syringes with PBS / 5 ml contains 1/5*106 number of stem cells extracted from human adipose tissue of diabetic rats was injected into the tail vein. Diabetes was induced by injection of streptozotocin (60 mg/kg) dissolved in citrate buffer, pH 4.5 intraperitoneally. VEGF and NGF levels in the hippocampus were measured by ELISA. The levels of VEGF and NGF were significantly reduced in the diabetic group compared to the control (P = 0.0001). On the other hand, VEGF levels in the diabetic + exercise + cell group were significantly higher than other groups (P = 0.0001). Also, these levels were significantly increased in the diabetes + cell and diabetes + exercise groups compared with the control diabetes group(P = 0.0001). On the other hand, the level of NGF in the diabetic cell group was significantly higher than that of the other groups except for the group of diabetes (P = 0.0001). Also, these levels were significantly increased in the diabetes + cell and diabetes + exercise groups compared with the control diabetes group (P = 0.0001). Generally, the results showed that the levels of NGF and VEGF in the training group, stem cell and also in the combined group were significantly increased compared to the control group for diabetes. Therefore, it seems that each of the interventions, especially their combination, can be a controller factor against diabetes due to an increase in neurotrophic and vascular effects.

The purpose of this study was to evaluate the changes in substrate oxidation during exercise with white tea consumption in obese men. Ten obese young men (age 19.00 ± 0.47 years, height 181.80 ± 4.32 cm, weight 104.20 ± 8.84 kg, BMI 31.20 ± 1.93 kg/m2, body fat percent 25.80 ± 2.62 %), take 500 ml of water or 500 ml of white tea one week apart after 8 h fasting in crossover and counterbalance model. One hour after use, while the gas analyzer was connected to them, they carried out an incremental exercise to exhaustion on a treadmill. The rate of fat and carbohydrate oxidation during exercise test were measured using indirect calorimetry. For each subject, the maximum fat oxidation (MFO) and the intensity of the MFO occurs (FATmax) were determined. Paired Sample t test showed that MFO (p = 0.011), and fat oxidation in the third stage (p = 0.023) in terms of white tea consumption was significantly higher than water intake. There was no significant difference in FATmax, time to exhaustion, maximum heart rate and maximum oxygen consumption between the two conditions. It seems that taking white tea one hourbefore exercise can increase fat oxidation in obese men.