درخت حوزه‌های تخصصی

Background: Researchers have studied practical applications of high-intensity interval training and hypoxic training. PGC-1α, IGF-I, and HIF-1α are generated from high-intensity interval training and affect muscle cells. Altitude training also produces HIF-1α, which induces erythropoietin and increases the number of red blood cells. However, due to the limit on training intensity and cycle, it was replaced by normobaric hypoxia training. Purpose: To investigate the effects of 2-day high-intensity interval training on muscular anaerobic metabolism at varying oxygen concentrations for 2 days. Method: Ten subjects performed 2 consecutive days of intermittent hypoxia-hyperoxic training (IHHT); intensity of training was determined by the sprint test results. IHHT comprised 4 sets of 3 repetitions for 40 seconds (4 × 3 × 40 s); the intensity and oxygen concentration were 80% of maximal effort and 13% oxygen for the first and third sets, and were 90% of maximal effort and 21% oxygen for the second and fourth set; participants walked for 3 min wearing an oxygen mask (O2 80%) before each set. Differences in biological parameters between the two days of training was analyzed by t-test. Results: The difference of mean lactate levels between two days were 0.96 ± 0.75 mmol/l at Set 3 (P = .003) and 1.05 ± 1.12 mmol/l at Set 4 (P = .016), respectively. Mean ammonia concentrations at Set 4 were 117.70 ± 29.8 μmol/l for the first day and 94.50 ± 14.45 μmol/l for the second day (P = .057). The difference of heart rate were 4.20 ± 5.05 min-1 at Set 1 (P = .027) and 4.00 ± 5.48 min-1 at Set 2 (P = .046). Conclusions: Two-day intermittent hypoxia-hyperoxic training affected lactate and heart rate.

Purpose: It has been well proven that type 2 diabetes is one of the most common non-communicable diseases leading to many complications and mortality every year. The aim of this study was to investigate the effect of resistance training on FTO and PPAR-y gene expression in muscle tissue of obese diabetic rats. Study design: This experimental study was performed on 12 male Wistar rats (10 weeks old and 220±20 g bodyweight). Methods: Animals received 6 weeks high-fat diet and then in order to induce type 2 diabetes an intraperitoneal injection of a single dose of 30 mg/kg freshly prepared streptozotocin (STZ) (Sigma, USA) solved in citrate buffer (pH 4.5) was performed. Diabetic rats were divided into two (Resistance and control) groups randomly. The resistance program included 6 weeks, 5 sessions per week. The muscle expression of FTO and PPAR-γ was measured using the real-time PCR method. Independent t-test and Analysis of covariance (ANCOVA) were applied to compare the means. Results: The muscle mRNA expression of PPAR-γ and body weight significantly increased after 6 weeks of resistance training (p=0.031, p=0.037; respectively) but there was no significant change in the muscle mRNA expression of FTO (p=0.317). Also, blood glucose significantly decreased in the training group compared to the control group (p=0.01). Conclusion: According to the results of this study, it can be noted that 6-week resistance training by decreasing glucose levels and increases insulin sensitivity, and the muscle expression of PPAR-γ plays a prominent role in the control and treatment of type 2 diabetes in obese patients.

Purpose:  Multiple Sclerosis (MS) is an autoimmune disease which is on the rise in recent years especially in Iran. Although there has been much progress in MS treatment, there is no definitive cure for it. Considering high prices of prescription drugs and their serious side effects as well as, impact of this illness on function efficiency of individuals, it seems that exercise training is one of the effective, cheap, and without side effects methods, in improvement of the performance of MS patients. In this regard, the present study aimed to provide comprehensive information on the background and the latest studies conducted to evaluate the effect of various exercise trainings (resistance, aerobic, core stability, Pilates, and combined) on this disease.  Methods :  An electronic search from 1994 to 2022 was performed in the Magiran, SID, PubMed, Google Scholar, and Scopus databases to find published articles. The keywords were multiple sclerosis, physical activity, exercise, training, aerobics, resistance, combined, core stability and Pilates. Different articles were selected and reviewed according to relation with subject. Results: The results indicated that various exercise training with different duration, intensity, and frequency cause different adaptations in people. Furthermore, regular continuous combined exercise training can be more effective than one type of exercise training in improvement and reduction of the symptoms of MS disease. The mechanism of improvement in combined exercise training can be justified due to the benefits of concurrent use of two or more types of training protocols. Conclusions: It can be said that the combined use of exercise trainings is the most useful and effective method for these patients. However, more studies on the best combination of exercise trainings for MS patients should be done in the future.

Purpose: Osteoporosis usually starts at a young age and progresses slowly over time. Therefore timely diagnosis of this disease plays an effective role in raising the level of health and public health in the society. The aim of this study was to investigate the relationship between some indicators of osteoporosis and bone mineral density of the pelvis in active elderly men. Methods: This study was semi-experimental. 25 active elderly men with the age range of 60 to 85 years were selected as available and with medical records. Anthropometric characteristics and serum indices of subjects were used as effective indices of osteoporosis. Pearson's correlation coefficient was used to find the relationship between bone mineral density of the pelvis and effector indices, data analysis was done using SPSS version 26 software. Results: The results of this research showed that in the active elderly men, there is a significant relationship between age (P=0.044), body mass index (BMI) (P=0.021), serum calcium (P=0.037) and phosphorus levels (P=0.046) and alkaline phosphatase (P=0.016), with bone mineral density (BMD) of the pelvis. No significant relationship was found between vitamin D with BMD of the pelvis (P=0.055). Conclusion: In general, the results show that there is a significant relationship between bone density and body mass index, calcium and serum alkaline phosphatase indices in active elderly men. Therefore, it is possible to use the serum levels of these indicators in predicting this disease, and exercise may also be one of the influencing factors, so the effect of exercise on other bone density indicators can be investigated.