900 resultados para Strength Training


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Background: Exercise training has been shown to improve exercise capacity in patients with heart failure. We sought to examine the optimal strategy of exercise training for patients with heart failure. Methods: Review of the published data on the characteristics of the training program, with comparison of physiologic markers of exercise capacity in heart failure patients and healthy individuals and comparison of the change in these characteristics after all exercise training program. Results: Many factors, including the duration, supervision, and venue of exercise training; the volume of working muscle; the delivery mode (eg, continuous vs. intermittent exercise), training intensity; and the concurrent effects of medical treatments may influence the results of exercise training in heart failure. Starting in an individually prescribed and safely monitored hospital-based program, followed by progression to an ongoing and progressive home program of exercise appears to be the best solution to the barriers of anxiety, adherence, and ease of access encountered by the heart failure patient. Conclusions: Various exercise training programs have been shown to improve exercise capacity and symptom status in heart failure, but these improvements may only be preserved with an ongoing maintenance program.

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The objectives of this study are to (1) quantify prior cardiopulmonary resuscitation (CPR) training in households of patients presenting to the Emergency Department (ED) with or without chest pain or ischaemic heart disease (IHD); (2) evaluate the willingness of household members to undertake CPR training; and (3) identify potential barriers to the learning and provision of bystander CPR. A cross-sectional study was conducted by surveying patients presenting to the ED of a metropolitan teaching hospital over a 6-month period. Two in five households of patients presenting with chest pain or IHD had prior training in CPR. This was no higher than for households of patients presenting without chest pain or IHD. Just under two in three households of patients presenting with chest pain or IHD were willing to participate in future CPR classes. Potential barriers to learning CPR included lack of information on CPR classes, perceived lack of intellectual and/or physical capability to learn CPR and concern about causing anxiety in the person at risk of cardiac arrest. Potential barriers to CPR provision included an unknown cardiac arrest victim and fear of infection. The ED provides an opportunity for increasing family and community capacity for bystander intervention through referral to appropriate training. (C) 2003 Published by Elsevier Science Ireland Ltd.

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Purpose: For treatment of various knee disorders, muscles are trained in open or closed kinetic chain tasks. Coordination between the heads of the quadriceps muscle is important for stability and optimal joint loading for both the tibiofemoral and the patellofemoral joint. The aim of this study was to examine whether the quadriceps femoris muscles are activated differently in open versus closed kinetic chain tasks. Methods: Ten healthy men and women (mean age 28.5 +/- 0.7) extended the knees isometrically in open and closed kinetic chain tasks in a reaction time paradigm using moderate force. Surface electromyography (EMG) recordings were made from four different parts of the quadriceps muscle. The onset and amplitude of EMG and force data were measured. Results: In closed chain knee extension, the onset of EMG activity of the four different muscle portions of the quadriceps was more simultaneous than in the open chain. In open chain, rectus femoris (RF) had the earliest EMG onset while vastus medialis obliquus was activated last (7 +/- 13 ms after RF EMG onset) and with smaller amplitude (40 +/- 30% of maximal voluntary contraction (MVC)) than in closed chain (46 +/- 43% MVC). Conclusions: Exercise in closed kinetic chain promotes more balanced initial quadriceps activation than does exercise in open kinetic chain. This may be of importance in designing training programs aimed toward control of the patellofemoral joint.

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The aim of this study was to compare the effects of two high-intensity, treadmill interval-training programs on 3000-m and 5000-m running performance. Maximal oxygen uptake ((V) over dot O-2max), the running speed associated with (V) over dot O-2max (nu (V) over dot O-2max), the time for which nu (V) over dot O-2max can be maintained (T-max), running economy (RE), ventilatory threshold (VT) and 3000-m and 5000-m running times were determined in 27 well-trained runners. Subjects were then randomly assigned to three groups; (1) 60% T-max (2) 70% T-max and (3) control. Subjects in the control group continued their normal training and subjects in the two T-max groups undertook a 4-week treadmill interval-training program with the intensity set at nu (V) over dot O-2max and the interval duration at the assigned T-max. These subjects completed two interval-training sessions per week (60% T-max = six intervals/session, 70% T-max group = five intervals/session). Subjects were re-tested on all parameters at the completion of the training program. There was a significant improvement between pre- and post-training values in 3000-m time trial (TT) performance in the 60% T-max group compared to the 70% T,,a, and control groups [mean (SE); 60% T-max = 17.6 (3.5) s, 70% T-max = 6.3 (4.2) s, control = 0.5 (7.7) s]. There was no significant effect of the training program on 5000-m TT performance [60% T-max = 25.8 (13.8) s, 70% T-max = 3.7 (11.6) s, control = 9.9 (13.1) s]. Although there were no significant improvements in (V) over dot O-2max, nu (V) over dot (2max) and RE between groups, changes in (V) over dot O-2max and RE were significantly correlated with the improvement in the 3000-m TT. Furthermore, VT and T-max were significantly higher in the 60% Tmax group post-compared to pre-training. In conclusion, 3000-m running performance can be significantly improved in a group of well-trained runners, using a 4-week treadmill interval training program at nu (V) over dot O-2max with interval durations of 60% T-max.

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Increased professionalism in rugby has elicited rapid changes in the fitness profile of elite players. Recent research, focusing on the physiological and anthropometrical characteristics of rugby players, and the demands of competition are reviewed. The paucity of research on contemporary elite rugby players is highlighted, along with the need for standardised testing protocols. Recent data reinforce the pronounced differences in the anthropometric and physical characteristics of the forwards and backs. Forwards are typically heavier, taller, and have a greater proportion of body fat than backs. These characteristics are changing, with forwards developing greater total mass and higher muscularity. The forwards demonstrate superior absolute aerobic and anaerobic power, and Muscular strength. Results favour the backs when body mass is taken into account. The scaling of results to body mass can be problematic and future investigations should present results using power function ratios. Recommended tests for elite players include body mass and skinfolds, vertical jump, speed, and the multi-stage shuttle run. Repeat sprint testing is a possible avenue for more specific evaluation of players. During competition, high-intensity efforts are often followed by periods of incomplete recovery. The total work over the duration of a game is lower in the backs compared with the forwards; forwards spend greater time in physical contact with the opposition while the backs spend more time in free running, allowing them to cover greater distances. The intense efforts undertaken by rugby players place considerable stress on anaerobic energy sources, while the aerobic system provides energy during repeated efforts and for recovery. Training should focus on repeated brief high-intensity efforts with short rest intervals to condition players to the demands of the game. Training for the forwards should emphasise the higher work rates of the game, while extended rest periods can be provided to the backs. Players should not only be prepared for the demands of competition, but also the stress of travel and extreme environmental conditions. The greater professionalism of rugby union has increased scientific research in the sport; however, there is scope for significant refinement of investigations on the physiological demands of the game, and sports-specific testing procedures.

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Background The reduction of exercise capacity because of fatigue and dyspnea in patients with heart failure can be improved with exercise training. We sought to examine the mechanisms of exercise training, as an adjunctive treatment strategy for patients with heart failure. Methods a reviewed the published data on the possible mechanisms of effect of exercise training in heart failure. Results Symptoms of heart failure may be explained on the basis of abnormal skeletal muscle perfusion and structure and endothelial function. Exercise training has been shown to engender changes in muscle structure and biochemistry and vascular function, although effects on cardiac function have not been detected uniformly and may require longer training periods. Conclusions A suitable, long-term program of exercise training may reverse unfavorable interactions among the heart, vessels, and skeletal muscles. These improvements may be preserved with an ongoing maintenance program.

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Biological nitrogen removal via the nitrite pathway in wastewater treatment is very important in Saving the cost of aeration and as an electron donor for denitrification. Wastewater nitrification and nitrite accumulation were carried out in a biofilm airlift reactor with autotrophic nitrifying biofilm. The biofilm reactor showed almost complete nitrification and most of the oxidized ammonium was present as nitrite at the ammonium load of 1.5 to 3.5 kg N/m3.d. Nitrite accumulation was stably achieved by the selective inhibition of nitrite oxidizers with free ammonia and dissolved oxygen limitation. Stable 100% conversion to nitrite could also be achieved even under the absence of free ammonia inhibition on nitrite oxidizers. Batch ammonium oxidation and nitrite oxidation with nitrite accumulating nitrifying biofilm showed that nitrite Oxidation was completely inhibited when free ammonia is higher than 0.2 mg N/L. However, nitrite oxidation activity was recovered as soon as the free ammonia concentration was below the threshold level when dissolved oxygen concentration was not the limiting factor. Fluorescence in situ hybridization analysis of cryosectioned nitrite accumulating nitrifying biofilm showed that the β-subclass of Proteobacteria, where ammonia oxidizers belong, was distributed outside the biofilm whereas the α-subclass of Proteobacteria, where nitrite oxidizers belong, was found mainly in the inner part of the biofilm. It is likely that dissolved oxygen deficiency or limitation in the inner part of the nitrifying biofilm, where nitrite oxidizers exist, is responsible for the complete shut down of the nitrite oxidizers activity under the absence of free ammonia inhibition.

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Ascorbic acid or vitamin C is involved in a number of biochemical pathways that are important to exercise metabolism and the health of exercising individuals. This review reports the results of studies investigating the requirement for vitamin C with exercise on the basis of dietary vitamin C intakes, the response to supplementation and alterations in plasma, serum, and leukocyte ascorbic acid concentration following both acute exercise and regular training. The possible physiological significance of changes in ascorbic acid with exercise is also addressed. Exercise generally causes a transient increase in circulating ascorbic acid in the hours following exercise, but a decline below pre-exercise levels occurs in the days after prolonged exercise. These changes could be associated with increased exercise-induced oxidative stress. On the basis of alterations in the concentration of ascorbic acid within the blood, it remains unclear if regular exercise increases the metabolism of vitamin C. However, the similar dietary intakes and responses to supplementation between athletes and nonathletes suggest that regular exercise does not increase the requirement for vitamin C in athletes. Two novel hypotheses are put forward to explain recent findings of attenuated levels of cortisol postexercise following supplementation with high doses of vitamin C.

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Changes in plasma zinc concentration and markers of immune function were examined in a group of 10 male runners (n = 10) following a moderate increase in training over four weeks. Seven sedentary males acted as controls. Fasting blood samples were taken at rest, before (T0) and after T4) four weeks of increased (+ 16 %) training and after two weeks of reduced (- 31 %) training (W. Blood was analysed for plasma zinc concentration, differential leucocyte counts, lymphocyte subpopulations and lymphocyte proliferation using incorporation of H-3-thymidine. The runners increased their training volume by 16 % over the four weeks. When compared with the nonathletes, the runners had lower concentrations of plasma zinc (p = 0.012), CD3(+) (p = 0.042) and CD19(+) lymphocytes (p = 0.010) over the four weeks. Lymphocyte proliferation in response to Concanavalin A stimulation was greater in the runners (p = 0.0090). Plasma zinc concentration and immune markers remained constant during the study. Plasma zinc concentration correlated with total leucocyte counts in the athletes at T6 (r = -0.72, p < 0.05) and with Pokeweed mitogen stimulation in the nonathletes at T6 (r = -0.92, p < 0.05). Therefore, athletes are unlikely to benefit from zinc supplementation during periods of moderately increased training volume.

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Este trabalho analisa o Programa de Residência Multiprofissional em Saúde, com objetivo de identificar como o Programa de Residência Multiprofissional em Saúde, desenvolvido pelo Ministério da Educação e pelo Ministério da Saúde a partir de 2005, tem se constituído como uma proposta de política de formação profissional para o SUS. Foi realizada pesquisa documental com análise de conteúdo que possibilitou configurar a Política Nacional de Gestão da Educação na Saúde, na área de formação do ensino superior, especificamente na pós-graduação, onde se situa a modalidade Residências Multiprofissionais. As legislações do Sistema Único de Saúde para a formação dessa política determinam diretrizes para a formação na área da saúde baseadas na integração ensino/Serviço. São eixos que se destacam no interior do processo de constituição da política de formação profissional e são as bases dos Programas de Residência Multiprofissional em Saúde. Constatou-se que houve, na primeira metade dos anos 2000, o surgimento de inúmeros atores (fóruns de residentes, coordenadores e preceptores) que estiveram presentes na luta para estruturação da Comissão Nacional de Residência Multiprofissional em Saúde, também presentes na disputa acirrada da composição e da luta pelo reconhecimento das Residências Multiprofissionais, a partir do ano 2005. Há um campo que coloca interesses em confronto e por onde caminha a definição da base legal para institucionalização do Programa. Polariza-se e ganha força posicionamentos corporativistas indo contra aos pressupostos do perfil profissional para a saúde. Ao mesmo tempo observa-se o esvaziamento das Residências na atenção básica e o movimento do Ministério da Saúde e do Ministério da Educação para implantar as Residências Multiprofissionais nos Hospitais Universitários Federais, direcionando especialmente aos serviços de alta complexidade. Os riscos podem ser observados na conformação da formação em saúde no plano da tarefa do fazer. Frente ao contexto de precarização do trabalho, fragiliza-se a presença dos residentes para cobrir o déficit de trabalhadores nas instituições de saúde, tornando necessárias uma intensa defesa e afirmação dos residentes enquanto profissionais em formação e não profissionais de serviço. Diante desse quadro fica a dúvida quanto ao papel das Residências Multiprofissionais nas transformações do modo de se produzir saúde e formação profissional. Por outro lado a observação dos vários aspectos vinculados à residência tem demonstrado também que elas, contraditoriamente, tem sido, ou podem ser, também um reduto importante de resistência à sucumbência dos novos contornos que vêm sendo desenhado no próprio SUS. E que apesar desse contexto, elas têm sido importantes como qualificação dos serviços e dos profissionais. Há um consenso em torno da importância das presenças dos residentes e dos tutores nos serviços, através dos seus questionamentos para rompimento com práticas de cunho conservador, pois a presença dos residentes nas equipes multiprofissionais pode assumir esse enfrentamento.

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O objeto de estudo dessa pesquisa é a política de segurança pública brasileira visando compreender o seu percurso ideológico e político no contexto de retomada e da consolidação da democracia no Brasil, após 21 anos de ditadura militar. Considerando o contexto no qual se verifica a existência de disputa política em torno da concepção de segurança pública, o objetivo geral deste trabalho é compreender a matriz estruturante da política de segurança pública no Brasil contemporâneo. Seu intuito visa responder à pergunta inicial e condutora do interesse que estrutura este trabalho, aqui apresentada nos seguintes termos: a política de segurança pública no Brasil após o restabelecimento das eleições diretas para a Presidência da República está em vias de transição, tendendo a assumir caráter democrático ou a força da tradição autoritária na cultura política brasileira tem-se garantido a sua continuidade neste campo da intervenção estatal? Ancoramos a nossa reflexão nas categorias teóricas de dominação, coerção e consenso no pensamento clássico de Hobbes, Marx, Weber e Gramsci, extraindo deles os elementos que nos auxiliam no entendimento da política de segurança pública brasileira. Para o estudo dessa política foi fundamental operarmos uma profunda revisão bibliográfica, especialmente para entender como a manutenção da ordem foi se desenhando no contexto brasileiro e como historicamente tem prevalecido um modelo de segurança pública marcado pelo autoritarismo. Entretanto, a partir da redemocratização brasileira há a emergência de outro paradigma para a política de segurança pública, a segurança cidadã, propondo, entre outras coisas, a reforma das instituições de segurança pública e a formação em direitos humanos nas instituições policiais. Para a análise do paradigma emergente de segurança, buscamos apoio no Programa Nacional dos Direitos Humanos e no Plano Nacional de Segurança Pública, documentos federais que representam a construção de uma nova intencionalidade para a segurança pública no Brasil. Finalmente, reconhecemos que, embora haja significativas reformas na segurança pública, tal política, diante da prevalência de um paradigma de segurança tradicional com fortes componentes autoritários, se encontra entre a segurança cidadã e a continuidade autoritária.

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Laparoscopy is a surgical procedure on which operations in the abdomen are performed through small incisions using several specialized instruments. The laparoscopic surgery success greatly depends on surgeon skills and training. To achieve these technical high-standards, different apprenticeship methods have been developed, many based on in vivo training, an approach that involves high costs and complex setup procedures. This paper explores Virtual Reality (VR) simulation as an alternative for novice surgeons training. Even though several simulators are available on the market claiming successful training experiences, their use is extremely limited due to the economic costs involved. In this work, we present a low-cost laparoscopy simulator able to monitor and assist the trainee’s surgical movements. The developed prototype consists of a set of inexpensive sensors, namely an accelerometer, a gyroscope, a magnetometer and a flex sensor, attached to specific laparoscopic instruments. Our approach allows repeated assisted training of an exercise, without time constraints or additional costs, since no human artificial model is needed. A case study of our simulator applied to instrument manipulation practice (hand-eye coordination) is also presented.

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Laparoscopic surgery (LS) has revolutionized traditional surgical techniques introducing minimally invasive procedures for diagnosis and local therapies. LSs have undeniable advantages, such as small patient incisions, reduced postoperative pain and faster recovery. On the other hand, restricted vision of the anatomical target, difficult handling of the surgical instruments, restricted mobility inside the human body, need of dexterity to hand-eye coordination and inadequate and non-ergonomic surgical instruments may restrict LS only to more specialized surgeons. To overcome the referred limitations, this work presents a new robotic surgical handheld system – the EndoRobot. The EndoRobot was designed to be used in clinical practice or even as a surgical simulator. It integrates an electromechanical system with 3 degrees of freedom. Each degree can be manipulated independently and combined with different levels of sensitivity allowing fast and slow movements. As other features, the EndoRobot has battery power or external power supply, enables the use of bipolar radiofrequency to prevent bleeding while cutting and allows plug-and-play of the laparoscopic forceps for rapid exchange. As a surgical simulator, the system was also instrumented to measure and transmit, in real time, its position and orientation for a training software able to monitor and assist the trainee’s surgical movements.