The Effects of 8 weeks of high intensity interval training and high intensity functional training on physical performance and volume of firefighters' self-contained breathing apparatus

Background and Purpose: Firefighting is a high-risk profession that requires high physical fitness, and it is important to have regular exercise to maintain optimal physical fitness and health. However, there is a little research on the best types and methods of training to improve the performance of firefighters and reduce the volume of self-contained breathing apparatus (SCBA) used in duty. Therefore, the purpose of this study was to investigate and compare the effect of 8 weeks of high-intensity interval and functional training on cardiorespiratory fitness (VO2max) and the used volume of SCBA in firefighters.Materials and Methods: Thirty-nine firefighters working in the fire department of Tehran participated in the study and were randomly allocated in the three groups of control, HIIT and HIFT. Subjects in HIIT group performed 8 weeks of Tabata exercises with body weight, which were 4 exercises in the first two weeks and were increased to 6 and 8 exercises in the 6th and 8th weeks, respectively. In each session, they had 10 min general warm up, thereafter they performed 8 sets of each exercise, where sets included 20 s activity followed by 10 s rest and 2 min rest was allowed between exercises. Subjects in HIFT group had similar program to the HIIT group, with the exception that the exercises they performed were those exercises in the standard simulated test for firefighters which were performed based on the Tabata methods (20 s activity followed by 10 s rest). Two days before training and 48 hours after the last training session the VO2max test (Bruce’s protocol) and simulated firefighting test were carried out.Results: The statistical analysis of the data showed that HIFT and HIIT caused a significant increase in maximal oxygen uptake (VO2max) and performance, and a significant decrease in the volume of SCBA used in firefighters (p<0.05), though, these changes were not significantly different between HIIT and HIFT groups (p<0.05). VO2max increased by 6.35% and 4.26% in HIFT and HIIT groups, and performance increased by 5.21 and 4.74%, following HIFT and HIIT, respectively. In addition, VO2/HR increased by 11.64 and 6.52% in HIIT and HIIT groups, respectively, while, the volume of SCBA used decreased by 14.41% and 11.44%, respectively. However, the results of repeated measures of ANOVA showed no significant between-group differences for RER (P=0.269), HR (P=0.595), VE (P=0.392), VE/VO2 ratio (P0.778) =) and VE/VCO2 ratio (P=0.778).Conclusion: According to the results of the present study it could be concluded that 8 weeks of HIFT and HIIT can improve cardiorespiratory fitness (VO2max), performance, and the volume of SCBA used in firefighters, and that performing these types of training based on the Tabata’s method is advised to firefighters

The effect of concentric-concentric isokinetic activity with restricted blood flow on serum VEGF levels in active elderly men

Purpose: Aging is a process of progressive reduction of physiological and functional factors. One of the important changes that occur during this period is the reduction of angiogenesis. Many studies have shown that sports activities can prevent the development of these factors. Therefore, the purpose of this study was to investigate the effect of concentric isokinetic activity (low intensity) with blood flow restriction on serum VEGF levels in active elderly men.  Methods: For this purpose, 10 healthy men at age range 60-80 years were selected through convenience sampling in a Tehran-based park (average weight: 77.8 ± 9.25 kg, height: 175.9 ± 2.92 cm, BMI: 25.15 ± 2.85kg/m2). Blood flow restriction was performed with a Doppler device to obtain 50% of the maximum restricted blood pressure for the session. Subjects performed four knee flexion and extension activities with 20% of one-repetition maximum and at an angular velocity of 30 degrees per second, complete flexion and extension of the leg. initially, they performed the first time with 30 repetitions and the other three times with 15 repetitions and with 30 seconds rest between each time. Before the start of the protocol, blood sampling was performed immediately and two hours after the activity, and serum VEGF was measured by ELISA. 2 × 3 repeated measures ANOVA was used to analyze the data after ensuring their normal distribution. Results: The results of data analysis showed that serum levels of VEGF, in response to concentric isokinetic activity with restricted blood flow, increased significantly compared to concentric isokinetic activity without restricted blood flow (P= 0.01). Conclusion: Therefore, it seems that in the elderly, the use of the blood flow restriction method, despite the low intensity of activity, had a significant effect on serum VEGF levels as one of the angiogenic factors in active elderly men

Effect of acute Ramadan fasting on muscle function and buffering system of male athletes

The aim of this study was to investigate the effect of acute Ramadan fasting (RF) on the muscle function and buffering system. Twelve male athletes with 8 years of professional sports experience (age, 23.2 ± 1.3 years, body mass index: 24.2 ± 2.2 kg/m2) participated in this study. The subjects were tested twice, 3 weeks after the beginning of RF and 2 weeks after the end RF. Muscle function, buffering capacity, and rating of perceived exertion (RPE) were measured during and after RF by using the Biodex isokinetic machine, blood gas analyzer, and RPE 6-20 Borg scale, respectively. Venous blood samples for pH and bicarbonate (HCO3-) were measured during and after RF by using the Biodex isokinetic machine, blood gas analyzer, and RPE 6-20 Borg scale, respectively. Venous blood samples for pH and bicarbonate (HCO3-) were taken immediately after 25 repetitions of isokinetic knee flexion and extension. Measures taken during isokinetic knee extension during RF were significantly lower than those after RF in extension peak torque (t = -4.72, p = 0.002), flexion peak torque (t = -3.80, p = 0.007), extension total work (t = -3.05, p = 0.019), extension average power (t = -4.20, p = 0.004), flexion average power (t = -3.37, p = 0.012), blood HCO3- (t = -2.02, p = 0.041), and RPE (Z = -1.69, p = 0.048). No influence of RF was found on the blood pH (t = 0.752, p = 0.476). RF has adverse effects on muscle function and buffering capacity in athletes. It seems that a low-carbohydrate substrate during RF impairs muscle performance and reduces the buffering capacity of the blood, leading to fatigue in athletes

Exercise role in improving the immune system and physical fitness during Corona pandemic period and associated exercise guidelines

A novel virus that expanded globally from China known as severe acute respiratory syndromecoronavirus 2 (SARS-CoV-2), causing Corona Virus Disease 2019 (COVID-19). Based on the pandemicand fast spreading characteristics of corona virus (COVID-19), it causes concerns for elderly individualsand those with chronic diseases. To lower the chances of spreading the coronavirus, and preventingthe social and economic burden, most of the credible medical centers and organizations haverecommended social distancing and isolations. Disclosure of gyms and sport centers and isolation hasresulted in inactivity in different individuals. The corona virus disease has led to challenges for keepingthe active lifestyle and it can induce some diseases due to inactivity such as obesity metabolicdisorders (e.g., diabetes), cardiovascular diseases, and other diseases that can increase hospitalreferral. Since this is a novel disease and although the effects of regular exercise on it has not beeninvestigated yet, exercise and active lifestyle through increasing energy expenditure, bodymetabolism, and improving physical and psychological fitness can result in increasing health, reducingvirus infection and in the case of having the corona disease it helps a quicker recovery. Since, coronadisease influences on the immune and cardiorespiratory system and the person’s physical fitness canbe effective in tolerating the disease side effects, this article expands on the effects of regular exerciseon immune system, viral infections (inflammation), cardiorespiratory system and physical fitness andat the end presents exercise guidelines for different populations

Effect of Resistance Exercise and Training and Principles of Prescribing it for Cardiovascular Patients

Introduction: The importance and necessity of preventing the occurrence of these diseases in order to maintain and promote health, has attracted the attention of many researchers to methods of preventing the occurrence of cardiovascular injury. Metabolic effects of muscle mass loss due to the natural aging process are caused by decreased muscle activity and lead to high prevalence of obesity, insulin resistance, type 2 diabetes, hyperlipidemia and cardiovascular disease. These risk factors cause disorders in the cardiovascular structure such as myocardial infarction, arterial stiffness and endothelial dysfunction, etc. Research also has shown that muscle strength is inversely related to all causes of death and the prevalence of metabolic syndrome. Therefore, the aim of this study was to provide safe resistance training methods for cardiovascular patients.&#x0D; Conclusion Resistance exercise is effective in preventing or reversing the functional, morphological and structural changes of the heart. Research shows that resistance training prevents the reduction of skeletal muscle mass and its function. This can also compensate for the functional decline caused by aging and disease. Because the methods of resistance training are various and are associated with many methodological problems, the study of the effect of exercise and resistance training in cardiovascular patients has always been controversial. This article reviews the findings of previous research examining the effects of the interaction between acute exercise and training in cardiovascular patients, and concludes the principles of prescribing resistance training in these patients. Overall, this study suggests that resistance training is beneficial even for the patients with CHF.</jats:p

The Effect of One Season of Preparation and Competition on Some Factors of Fibrinolysis, D-dimer, and CRP in Professional Athletes

Background and Objectives: The fibrinolytic system is an important physiological mechanism, the function of which is decomposition of fibrin strands in blood vessels. In the present study, the effect of one season of preparation and competition, was investigated on fibrinolysis, D-dimer, and CRP indices in professional soccer players. &nbsp; Methods: In this semi-experimental study, 10 soccer players of Sanat Naft Abadan (age, 22.5&plusmn;2.7 years; weight, 71&plusmn;4kg; height, 178.5&plusmn;4.5cm; BMI, 22.2&plusmn;0.4kg/m2), participated in this study. The subjects performed one season of soccer preparation and competition, which lasted about 10 months. Blood samples (for measuring t-PA, PAI-1, D-dimer, and CRP), were taken in four stages: before the preparation season, after the preparation season, half-season, and at the end of competition season. Data were analyzed using repeated ANOVA and Bonferroni tests. &nbsp; Results: The training period caused a significant change in t-PA (p=0.003) and PAI-1 (p=0.005) resting levels, but caused no change in D-dimer and CRP resting levels. The paired analysis of the data showed a significant difference between the resting levels of t-PA (p=0.002) and PAI-1 (p=0.004) before the preparation period and after the competition season. &nbsp; Conclusion: According to the findings of this research, training causes an increase in the fibrinolysis system potential, hence, this may cause a decrease in the formation of thrombosis in professional soccer players. &nbsp; &nbsp; &nbsp