Journal of Sport Biosciences
Year:2018 | Volume:10 | Issue:3|Papers Count:9

Training has beneficial effects on the health of brain. The aim of this study was to evaluate the effect of resistance training with different intensities on serum levels of BDNF, Claudin11, and functional factors in MS patients. 30 women with MS (mean age 36. 1 ± 1. 8 years) were selected purposively, and were randomly divided into 3 groups: experimental 1 (resistance training with an intensity of 60% 1RM for 12 weeks, 3 sessions per week), experimental 2 (training with an intensity of 85% 1RM) and control (without regular training). Blood samples were collected in two steps (48 hours before the first training session and after the last training session). Results of the ELISA method and ANOVA with repeated measures showed that after 12 weeks, serum levels of BDNF in both experimental groups increased significantly compared with the pretest (P=0. 001). This increase was also significant in experimental 1 group compared with the control group (P=0. 002). Also, serum levels of Claudin11, muscle endurance and balance increased significantly in experimental groups in posttest compared with the pretest while fatigue decreased significantly (P=0. 001). These changes were significant in experimental groups compared with the control group. These findings showed that resistance training improves balance, fatigue and muscle endurance and increases levels of Claudin11 which is an important factor in the development of myelin sheath of nerve fibers. Also, an increase in BDNF levels which play a vital role in developing, maintaining and restoring nervous system was observed. In addition, in most cases, moderate intensity resistance training had an effect similar to high intensity training.

The aim of this study was to determine the effect of 8 weeks of aerobic exercise on resistin, glycated hemoglobin, indicator of insulin resistance and some cardiovascular risk factors in obese women with type 2 diabetes. 22 obese sedentary women with type 2 diabetes in Kermanshah (mean age 44. 95± 2. 33 yrs, weight 78. 88± 0. 82 kg, height 161. 11± 5. 45 cm) were randomly divided into 2 groups (each group 11 subjects): experimental and control. The experimental group performed aerobic exercises for 8 weeks (3 sessions per week, each session 60 minutes) with 60-80% of maximum heart rate. Blood samples were collected 2 days before and after the intervention. Independent t test was used to compare the intergroup differences and dependent t test was used to compare the intragroup results. After the intervention, weight, body fat percent, insulin, HbA1c, hc-CRP, LDL-C (P=0. 05), fasting blood glucose (P=0. 032), insulin resistance, resistin (P=0. 04), cholesterol (P=0. 028) and TG (P=0. 014) significantly decreased in the experimental group compared to the control group. HDL-C and BMI levels had no significant differences between the groups. Weight (P=0. 02), fat percent (P=0. 01), glucose (P=0. 004), insulin (P=0. 031), resistin (P=0. 024), TG (P=0. 039), BMI, HbA1c, hc-CRP, LDL-C (P=0. 05), insulin resistance and cholesterol (P=0. 045) significantly decreased in the experimental group in the posttest compared with the baseline. The improved insulin resistance and decreased inflammatory markers and glycated hemoglobin reduce the potential risk of cardiac diseases and complications and diabetes and regular aerobic exercise can influence controlling the complications of this disease.

The aim of this study was to investigate the effect of hypobaric hypoxia following six weeks of high intensity interval training on the levels of SP-A in lungs of male Wistar rats. 20 rats (3 weeks old, mean weight 68 ± 9 g) were randomly divided to 4 groups: control 6 weeks (n=5), control 9 weeks (n=5), training 6 weeks (n=5) and training + hypobaric hypoxia (n=5) after 2 weeks of familiarity with the environment. Interval training group performed the program for six weeks, 5 sessions a week, each session 30 minutes at a speed of 15-70 m/min. The rats in hypobaric hypoxia group lived in rodent hypoxia chamber from week 7 to week 9 after the end of the training period. ELISA kit was used to measure the levels of lung SP-A. The data were analyzed using one-way ANOVA at P≤ 0. 05. The results showed that SP-A levels increased significantly in the 6 week training group compared with the control group while the SP-A levels in the hypoxia group significantly decreased compared with the control and training groups. Regarding the significant reduction of SP-A levels in the hypobaric hypoxia group, it seems that the interval hypoxia induced adaptation has been properly able to inhibit the pathophysiologic effects of high intensity interval training, to improve inflammatory markers and lung cell injury and strengthen lung immune system, which requires further research in this field.

The aim of this study was to investigate the effects of high intensity interval training (HIIT) and moderate intensity continuous training (MICT) on mitochondrial content and PGC-1α of subcutaneous adipose tissue in obese male rats. 40 male rats after inducing obesity with high fat diet (for 10 weeks), 8 rats from the high-fat diet group (O) and 8 rats of the standard diet group (C) were sacrificed and other obese rats were randomly divided into 3 groups: obesity control (OC), moderate intensity continuous training (MICT) and high intensity interval training (HIIT). The HIIT protocol included 10 bouts of 4-min. activity with the intensity equivalent to 85-90% vo2max and 2-min. active rest intervals. MICT protocol was carried out with the intensity of 65-70% VO2max with a covered distance similar to HIIT protocol for 12 weeks and 5 sessions per week. Western Blot method was used to measure PGC-1α and RT-PCR method was applied to measure mtDNA gene expression. Data were analyzed using ANOVA, ANCOVA and Bonferroni tests. The level of significance was considered as P≤ 0. 05. The results of data analysis showed that HIIT and MICT drastically increased protein contents of PGC-1α and mtDNA expression (P<0. 05). However, HIIT had more effects (P<0. 05). Generally, it seems that HIIT and MICT increase mitochondrial biogenesis in subcutaneous adipose tissue while the effects of HIIT are drastically higher.

The aim of this study was to compare the effect of high intensity interval training (HIIT) and continuous endurance training (E) on gene expression of adiponectin and TNF-α in type 2 diabetic rats. 24 Wistar rats (weight 160 ± 10 g) were divided into three groups: control, high intensity interval training and continuous endurance training after 7 months of high-fat diet containing fructose. The training groups performed the training protocol for 8 weeks / 5 days a week. The gene expression of adiponectin and TNF-α were measured from visceral fat tissue and glucose and insulin were measured from plasma and insulin resistance index was calculated. Data were analyzed by ANOVA and Pearson correlation. Both types of training significantly increased the expression of adiponectin (P=0. 016), but there was no significant difference between the two training groups (P=0. 932). The gene expression of TNF-α decreased in training groups and this decrease was more prominent in the HIIT group (P=0. 001). There was a significant relationship between reduction of insulin resistance and reduction of TNF-α gene expression (P<0. 001, r=0. 09) and increase of adiponectin gene expression (P=0. 002, r=-0. 7). HIIT may have an effective role in the balance between anti-inflammatory and inflammatory factors and regulation of insulin resistance in rats with type 2 diabetes.

During high intensity sport activities, tissues like liver, kidney and intestine experience hypoxia situation due to the ischemia following physical activity that finally increases free radicals. The aim of this study was to investigate the effect of 8 weeks of endurance training on glutathione peroxidase (GPX) and Malondialdehyde (MDA) of gastrocnemius muscle, heart and liver tissues in male Wistar rats. 12 male Wistar rats (mean weight= 234. 47± 25. 97 g, age=8 weeks) were randomly divided into two groups: control (n=6) and high intensity endurance training (n=6) after one week of familiarization. Endurance training included 8 weeks, 5 sessions a week on a rodent treadmill. The speed and duration of running were 10 m/min. and 30 min. at the first week respectively and reached 35 m/min. (equal to 80-%85 of Vo2 max) and 70 min. at the last week. The results of independent t test showed that high intensity endurance training significantly decreased GPX in heart (P=0. 001) and liver (P=0. 001) tissues compared with the control group. Also, MDA levels of heart (P=0. 03) and liver (P=0. 045) tissues in training group increased significantly compared with the control group. These findings showed that different tissues have different oxidative responses to similar training, that is to say high intensity endurance training imposes oxidative stress on heart and liver tissues more than gastrocnemius muscle.

The most important changes associated with aging in the body are the deterioration and destruction of muscle mass and a dramatic decrease in the size and mass of the skeletal muscle that result from increased gene expression and secretion of the myostatin protein. The aim of this study was to investigate the effect of 8 weeks of elastic band resistance training on serum myostatin and body composition in elderly women. In this quasi-experimental study, 26 elderly women with a mean age of 65. 81± 0. 69 were voluntarily selected as the subjects. Subjects were randomly divided into two groups: experimental (n=13) and control (n=13). The experimental group performed the elastic band resistance training protocol for 8 weeks, 3 sessions per weeks and 60 minutes each session. Blood samples were collected before the first training session and 48 hours after the last session. ELISA method was used to measure biochemical variables and ANCOVA was used to analyze the data at a significance level of PP=0. 014) and myostatin (P=0. 002) in the intervention group compared with the control group, but BMI and TG decrease and HDL increase were not significant. According to these findings, elastic band resistance training reduced myostatin, changed lipid profile and could be a good training method for the elderly with simplicity and functionality.

The elderly, despite their need to resistance training, usually abstain from these types of training especially at high intensities. One of the alternative methods is resistance training with blood flow restriction. Therefore, the present study aimed at investigating the effect of resistance training with and without blood flow restriction on muscle strength, muscle endurance and serum concentrations of CAF and P3NP in elderly women. 40 elderly women (mean age of 62± 3 years) were selected for this study. Then, they were randomly divided into four equal groups (n=10 for each group): resistance training with blood flow restriction (4 sets of 30, 15, 15, 15 repetitions, 20– 30% 1RM), resistance training without blood flow restriction (4 sets of 30, 15, 15, 15 repetitions, 20– 30% 1RM), traditional training (4 sets of 8-12 repetitions, 80% 1RM), and control. Blood samples and tests were taken before and after 12 weeks of training. ANOVA with repeated measures was used to assess the effects of training. Lower and upper extremity muscle strength and endurance significantly increased in three training groups compared with the control group (P<0. 05). There was no significant difference among three training groups (P>0. 05). Also, none of the training protocols had a significant effect on plasma levels of CAF (P=0. 94) and P3NP (P=0. 94). Therefore, no significant difference was observed among the three training groups in improving the effects of resistance training so it can be asserted that low intensity resistance training with and without blood flow restriction, similar to traditional training, resulted in desirable changes in physical factors of the elderly women.