This microcirculatory study compared the effects on oxygen transport of two hemodilution fluids: HBOC-201 (Biopure Corp., Cambridge, MA) a Hemoglobin-Based Oxygen Carrier (HBOC), and 5.9% Human Serum Albumin (HSA) an iso-oncotic non-oxygen carrying colloid solution. Measurements using intravital microscopy were made on the spinotrapezius muscle of male, Sprague-Dawley rats. Interstitial PO2 was measured using phosphorescence quenching microscopy, and recorded before and after isovolemic hemodilutions (HD) at hematocrits of 40% (baseline), 30% (moderate HD) and 15% (severe HD). Oxygen consumption (VO2) of the spinotrapezius muscle was derived from PO2 recordings following the rapid inflation of a plastic bag placed around the objective. When the bag was inflated, blood flow in the muscle was arrested and PO2 rapidly fell over several seconds; the rate of decline of PO2 was proportional to VO2. For moderate HD (Hct ~ 30%) with HBOC-201, interstitial PO2 did not change from baseline conditions (Hct ~ 40%), while HD with HSA showed a decrease. For severe HD (Hct ~ 15%) both PO2 and VO2 were significantly lower for the HSA group than for the HBOC-201 group. These findings indicate that HBOC-201 maintains both a higher PO2 and VO2 during hemodiluted states compared with a non-oxygen carrying colloid solution (HSA). Furthermore, 5.9% HSA does not affect the mean arterial pressure (MAP) and vessel diameters, whereas HBOC-201 causes vasoconstriction, and consequently an increase in MAP. However, the vasoconstriction is not uniform among different branches of the arteriolar network, and most of the changes occur in the larger vessels, i.e., feed and arcade arterioles, while minimal in smaller vessels, i.e., transverse arterioles. In addition, findings show that MAP and vessel diameters return to baseline within 1-3 hours, implying that vasoconstriction and hypertension caused by HBOC-201 are acute responses.

In resting muscle, blood flow is regulated to meet the demand for O2 by the tissue. A modified ischemia (I)/reperfusion(R) investigation was systematically run and PISFO2, PaO2, Q and VO2 were observed. Twenty-nine spinotrapezius muscles from male Sprague-Dawley rats (284±20 grams) were surgically exteriorized for intravital microscopy to test a model relating blood flow, O2 supply and O2 demand. The model can aid in the understanding of the regulation of tissue PO2. The interstitial PO2 (PISFO2) and perivascular PO2 (PaO2) measurements were made using phosphorescence quenching microscopy (PQM). O2 consumption (VO2) values were obtained with a quasi-continuous, flash-synchronized, pressurized airbag to initiate ischemia and sample the rate of O¬2 change (dPO2/dt). Centerline red blood cell velocity was measured with an Optical Doppler Velocimeter and converted to flow using vessel diameter. 5-, 15-, 30-, 60-, 300- and 600-second ischemic durations were used to observe changes in PISFO2, Q, and VO2. A critical point was observed following 30 seconds of (I) where dPISFO2/dt during recovery was the fastest (4.25±0.72 mmHg/s) and was 1.00±0.16 mmHg/s following 600 seconds. Flow recovery, dQ/dt, peaked to 3.88±0.64 (µl•min-1)/s after 60 seconds of (I) but significantly dropped to 2.83±0.55 (µl•min-1)/s following 300 seconds of (I) but increased to 2.92±0.45 (µl•min-1)/s following 600 seconds. This gives evidence to a no-reflow phenomenon occurring in the extended periods of ischemia. A peak in VO¬2 to 309.2±45.0 nl O2/cm3•s with a time course of 160 seconds occurred following 600 seconds of ischemia. As the ischemic duration decreased, the time course and peak VO2 also decreased. VO2 following 300 seconds of (I) was significantly higher than 5-60 seconds of (I) (p <0.05) but was not significantly different from 600 seconds of (I). The information collected during the Q and VO2 studies can be incorporated into a factor, M, that relates VO2, Q and ∆PO2. M calculated for the recovery of 5- through 60-second (I) groups reasonably relates the three variables due to consistency and little variability. However, recovery in 600- and especially 300-second (I) groups showed higher variability in M which requires more consideration.

The aim of this thesis was to determine the effect of driving in a wheelchair and walking on crutches on the energy expenditure and cardiopulmonary system in people with lower limb amputation. For this measurement we used a device Metamax 3B made by Cortex, functioning by measuring the concentration of oxygen and carbon dioxide in the breathing air, and a sporttester made by Polar. On the basis of oxygen consumption is possible to determine an energy expenditure during the activity. Our study was attended by 11 probands (men), patient of long-term hospital in Motol Hospital. Nine probands were amputated from vascular causes, one from the traumatological causes and one from the other causes. Probands rode (or walked) for four minutes back and forth along the corridor thirty meters long. They were instructed to ride (walk) at a speed to fit their needstand to also keep the same pace for a defined period of time. Walking on crutches without prosthesis managed only three of the testing file. During the study, these values were measured: distance traveled, average speed, oxygen consumption (VO2, VO2/kg, VO2 peak), carbon dioxide output (VCO2), respiratory exchange ratio (RER), tidal volume (VT), breathing frequention (BF), minute ventilation (MV), heart rate (HR), energy expenditure and performance. In this work...

Orientador: Vilmar Baldissera / Resumo: A organização das variáveis do exercício resistido altera respostas do estresse psicobiológico, da demanda energética, predominância do substrato energético utilizado durante a prática do exercício e também de lipólise. Desta maneira é fundamental estudar os efeitos das variáveis do exercício resistido sobre as respostas citadas. Os estudos sobre as respostas ao estresse provocado pelo exercício resistido estão voltados, principalmente, para o volume e intensidade. Outra variável pode influenciar sobre estas respostas, a duração da carga. Assim os objetivos deste estudo são: a) Verificar a influência da duração da carga sobre o estresse psicobiológico; b) Avaliar as respostas da demanda energética a diferente duração de carga; c) Determinar o substrato energético predominante durante a execução dos protocolos; d) Investigar o efeito da duração da carga sobre a lipólise. Participaram da pesquisa 16 voluntários do sexo masculino com mais de três meses de pratica em musculação, portanto familiarizados com os exercícios convencionais de academias propostos neste trabalho, com idade média de 29,31 ± 5,26 anos, saudáveis, sem diagnósticos de doenças que impossibilitem a prática de atividade física. Os participantes visitaram o laboratório em cinco ocasiões: na primeira assinaram o TCLE, ocorreu a aplicação do PAR-Q e teste de 1RM em todos exercícios que constituem as sessões. Na segunda visita foi realizada a familiarização com os procedimentos experimentais. Na terceira e quarta v... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The organization of the variables of the resistance exercise changes the responses of psychobiological stress, energy expenditure, predominance of the energy substrate used during exercise and lipolysis. In this way it is fundamental to study the effects of the variables of the resistance exercise on the cited answers. Studies on the responses to stress caused by resistance exercise are mainly focused on volume and intensity. Another variable can influence on these responses is the time under load. Thus the purpose of this study was: a) To verify the influence of the time under load on the psychobiological stress; b) Evaluate the responses of the energy expenditure to different time under load; c) Determine the predominant energy substrate during the execution of the protocols; d) Investigate the effect of the time under load on lipolysis. Sixteen male subjects with more than three months of practice in bodybuilding participated in the study, so they were familiar with the conventional exercises of academies proposed in this project, with a mean age of 29.31 ± 5.26 years, healthy, without diagnoses of diseases that make it impossible the practice of physical activity. The subjects visited the laboratory on five occasions: the first one signed the informed consent, the application of the PAR-Q and the 1RM test occurred in all exercises that constitute the sessions. During the second visit, familiarization with the experimental procedures was performed. In the third and fourth ... (Complete abstract click electronic access below) / Doutor

Crianças com mielomeningocele (MMC) apresentam anormalidades primárias no fechamento do tubo neural com extrusão de tecido nervoso. Alterações secundárias, como a paraplegia, podem comprometer o desempenho cardiopulmonar e a função autonômica cardiovascular, sendo ainda maior, nos indivíduos que são dependentes exclusivamente de cadeira de rodas. Embora a literatura científica tenha amplamente estudado as manifestações clínicas dos diferentes níveis da MMC, pouca atenção tem sido dada à disfunção cardiopulmonar. A análise da função autonômica cardiovascular assim como a avaliação da capacidade cardiopulmonar, pelo consumo máximo de oxigênio (VO2max), tem sido utilizada como forma de predizer fatores de risco relacionados à saúde, mas o teste cardiopulmonar que é o padrão ouro, requer especificidades que limitam sua ampla utilização. Objetivos: Analisar a capacidade cardiopulmonar de crianças e adolescentes cadeirantes com mielomeningocele e comparar com a do seu respectivo controle, e aplicação de teste indireto a fim de estimar o VO2max nas crianças e adolescentes com MMC. Métodos: Participaram desse estudo transversal 22 crianças e adolescentes, de ambos os sexos, com idade entre 8 e 15 anos, separadas em dois grupos: Grupo Mielomeningocele (GM), composto por 11 crianças e adolescentes com mielomeningocele que não deambulam (estritamente usuários de cadeira de rodas); e Grupo Controle (GC), composto por 11 crianças e adolescentes saudáveis pareados por sexo, idade, massa corporal e/ou estatura. Foram obtidos dados antropométricos; composição corporal por bioimpedância elétrica; classificação do nível de maturação pelo índice de Tanner; nível de atividade física pelo Questionário Internacional de Nível de Atividade Física; avaliação da força muscular isométrica dos abdutores de ombro, flexores e extensores de cotovelo, pelo dinamômetro Handheld e força muscular de preensão palmar pelo dinamômetro de Bulbo; avaliação da Variabilidade da Frequência Cardíaca e da Pressão Arterial (VFC e VPA) e da Sensibilidade Barorreflexa Espontânea (SBRE); teste cardiopulmonar em cicloergômetro de membro superior (teste direto = TD); e, teste indireto (TI) seguindo método proposto por Franklin et al.,(1990) para estimar VO2max. Resultados: os grupos não apresentaram diferença estatística com relação à antropometria e força muscular (p > 0,05), porém o GM apresentou incremento de aproximadamente 6kg de massa gorda (p 0,05). No teste cardiopulmonar, o GM apresentou reduzido valor de VO2pico comparado ao seu controle indicando diferença significativa entre os grupos (p 0,05). O VO2pico correlacionou-se positivamente com dados antropométricos, massa magra e força muscular. Os valores de VO2max estimado pelo TI foram menores que os valores reais obtidos no TD, sofrendo uma variação de 24 à 56%; por outro lado, os dados de FCmax e FC de repouso não apresentaram diferença entre os testes. Com relação à função autonômica cardiovascular, os parâmetros espectrais da VFC não apresentaram diferença significativa entre os grupos, mas os valores de baixa frequência na VPA e a SBRE estavam reduzidos no GM (p < 0,05). Conclusão: crianças e adolescentes com MMC apresentam menor capacidade cardiopulmonar que seus controles saudáveis, e reduzida sensibilidade barorreflexa espontânea com baixo controle simpático na VPA, indicando predisposição a eventos cardíacos tardios. E ainda, o método indireto selecionado não se mostrou ideal para estimar o VO2max nos voluntários do presente estudo, subestimando os valores reais, mas permitiu alcançar valores de FCmax prevista. Este pode ser um modelo de teste de esforço máximo, que necessita ser explorado nessa população. Uma proposta de condicionamento cardiopulmonar necessita ser desenvolvida para esta população. / Children with myelomeningocele (MMC) present primary abnormalities in neural tube with nerve tissue extrusion. Secondary alterations, such as paraplegia, can compromise the cardiopulmonary performance and cardiac autonomic function, mainly in individuals who are exclusively dependent on a wheelchair. Although the scientific literature has extensively studied the clinical manifestations of MMC and their different neural lesion levels, poor attention has been addressed to cardiopulmonary dysfunction. Evaluation of cardiac autonomic function and cardiopulmonary capacity using maximum oxygen uptake (VO2max) has been used to predict risk factors related to health, but this gold standard technique requires specificities that limit its widespread use. Objectives: To analyze the difference cardiopulmonary capacity of children and adolescents with myelomeningocele unable to walk and his or her matched control by detecting data that predispose to cardiovascular risks, and using an indirect test in order to estimate the VO2max in children with MMC. Methods: Twenty two (n = 11) children and adolescents participated of this cross-sectional study, both sexes, aged 8 15 years, separated into two groups: Group Myelomeningocele (GM), with 11 children and adolescents with myelomeningocele unable to walk (wheelchair users); and Control Group (CG), with 11 healthy children and adolescents matched for sex, age, weight and/or height. The data obtained were: Anthropometric data; body composition by bioelectrical impedance analysis; index maturation classification by Taner; level of physical activity by IPAQ; isometric muscle strength of shoulder abductors, elbow flexors and extensors using Handheld dynamometer, and grip muscle strength using bulb dynamometer; Spontaneous baroreflex sensitivity (SBS) and heart rate and blood pressure variability (HRV and BPV) evaluation; cardiopulmonary exercise testing on a cycle ergometer of upper limb (direct test = DT); and indirect test following the method proposed by Franklin et al., (1990) to estimate VO2max. Results: Anthropometry data and muscle strength did not present significant difference between analyzed groups (p > 0.05). GM presented approximately 6kg increased fat mass than CG (p 0.05). By cardiopulmonary test, GM presented reduced VO2peak compared to GC, indicating a significant difference between groups (p 0.05). The VO2peak have positive correlation with anthropometric data and fat free mass and muscle strength. The VO2max in DT varied between 2456% higher than those on the IT, but rest and maximum HR mean value comparisons showed no statistical difference between the tests. Considering cardiac autonomic function, no difference was observed to spectral parameters of HRV, but low frequency of BPV and the SBS were significantly lower in GM (p < 0.05). Conclusion: Children with MMC present reduced cardiopulmonary capacity than their healthy peers and reduced spontaneous baroreflex sensitivity and sympathetic control on BPV, indicating some predisposition to risk of cardiovascular event. And yet, VO2max values estimated by the chosen IT underestimated the DT values and were not applicable to this population; however, they may represent a potential model to test maximal exercise and obtain maximal HR values, which need to be explored further in this population.

Sabe-se que as diferentes respostas metabólicas advindas da realização de um exercício físico são influenciadas por fatores como idade, gênero, estado nutricional, assim como pelas próprias variáveis do exercício físico, em especial a intensidade e duração. Embora estas últimas variáveis sejam bastante estudadas, há uma lacuna na literatura sobre o comportamento do consumo de oxigênio (\'VO IND.2\'), gasto energético e lactacidemia quando diferentes exercícios são realizados na intensidade do limiar anaeróbio (AT). Além disso, não há relatos sobre uma possível fase estável do lactato em exercício resistido. Desta forma, a proposta deste estudo foi primeiramente verificar a possibilidade de identificação do AT em oito exercícios resistidos e posteriormente analisar o \'VO IND.2\', gasto energético e lactacidemia durante e após os exercícios em esteira, circuito, circuito/esteira e esteira/circuito, ambos realizados na intensidade do AT e com similar duração de execução de movimento. Para tanto, foram avaliados oito indivíduos do gênero feminino, saudáveis e fisicamente ativas, submetidas aos testes de determinação de uma repetição máxima (1RM), identificação do AT em oito exercícios resistidos, identificação do AT no exercício em esteira e realização dos protocolos de exercícios em esteira, circuito, circuito/esteira e esteira/circuito. Os resultados demonstraram a possibilidade de identificação do AT em todos os exercícios propostos. Durante o exercício, as variáveis metabólicas (\'VO IND.2\' e gasto energético) no exercício em esteira foram significativamente maiores quando comparadas aos exercícios em circuito, circuito/esteira e esteira/circuito. Nenhuma diferença significante foi constatada entre os protocolos circuito/esteira e esteira/circuito, para ambas as variáveis mencionadas. Já o exercício em circuito mostrou ser estatisticamente menor que os demais protocolos. No componente rápido do excess postexercise oxygen consumption (EPOC), o \'VO IND.2\' e gasto energético no exercício em esteira foram significativamente diferentes dos exercícios em circuito e em esteira/circuito. O exercício em circuito mostrou ser estatisticamente diferente do circuito/esteira, assim como também foi verificada uma diferença entre os protocolos mistos, para \'VO IND.2\' e gasto energético (p < 0,05). A duração e magnitude do \'VO IND.2\' no componente lento do EPOC não foram estatisticamente diferentes entre os protocolos, porém uma diferença foi constatada (p < 0,05) na magnitude da produção calórica entre os protocolos esteira e esteira/circuito, neste mesmo período de tempo. Nossos resultados não encontraram nenhuma diferença na duração total do EPOC entre os protocolos estudados. Ao computar o gasto energético total da sessão, somente o exercício em circuito apresentou um dispêndio significativamente maior em relação às calorias dispendidas apenas durante a realização deste exercício. Em relação à lactacidemia, foi possível identificar uma fase estável do lactato nos exercícios em esteira e em circuito. Conclusões: a realização de diferentes tipos de exercício exerce influência sobre o \'VO IND.2\' e gasto energético durante e após o exercício, ao passo que a ordem de execução dos mesmos em uma única sessão, para essas mesmas respostas metabólicas, só é influenciada no período pós-exercício. A duração total do EPOC independe da realização de diferentes tipos de exercícios, assim como da ordem de execução. Além disso, há a existência de uma fase estável do lactato em exercício resistido, quando realizado em forma de circuito. / It\'s known that differents metabolic responses that come from the practice of physical exercises are influenced by factors, such as age, gender, nutritional condition, as well as by their own exercise variable, in especially the intensity and duration. Although the latter variables are well studied, there is a gap in the literature about the behavior of oxygen consumption (\'VO IND.2\'), the energy expenditure and \"lactacidemia\" when different exercises are performed in the intensity of the anaerobic threshold (AT). In addition, there is no account about a possible stable phase of the lactate in a resistance exercise. This way, the proposal of this study was first to verify the possibility of identification of the AT in eight resistance exercises and then to analyze the \'VO IND.2\', the energy expenditure and the \"lactacidemia\" during and after the exercises at a treadmill, at a circuit, at a circuit/treadmill and at a treadmill/circuit, all done in the intensity of the AT and with similar duration of the movement execution. For this, eight female participants, healthy and physically active, were evaluated, submitted to tests of determination of a maximum repetition (1RM), identification of the AT in eight resistance exercises, identification of the AT in a treadmill exercise and the development of the protocols of exercise at a treadmill, at a circuit, at a circuit/treadmill and at a treadmill/circuit. The results demonstrated the possibility of identification of AT in all exercises. During exercise, the metabolic variables (\'VO IND.2\' and energy expenditure) in the exercise at the treadmill were significantly higher when compared to the exercises in circuit, circuit/treadmill and treadmill/circuit. No significant differences were found between the protocols circuit/treadmill and treadmill/circuit, for both variables mentioned. When it concerns the exercise in the circuit, it showed to be statistically lower than the other protocols. In the fast component of the excess postexercise oxygen consumption (EPOC), the \'VO IND.2\' and the energy expenditure at the treadmill exercise were significantly different when compared to the exercises at the circuit and at the treadmill/circuit. The exercise at the circuit was statistically different from the circuit/treadmill, and it was also verified a difference between the mixed protocols for the \'VO IND.2\' and the energy expenditure (p < 0,05). The duration and the magnitude of the \'VO IND.2\' in the slow component of the EPOC were not statistically different between the protocols, but there was a difference (p < 0,05) in the magnitude of the calorific production between the treadmill and the treadmill/circuit protocols. Our results didn\'t find any difference in the total duration of the EPOC in the protocols analyzed. When determining the total energy expenditure of the session, only the exercise at the circuit showed a significantly bigger energy expenditure in comparison with the expended calories just during the exercise. Concerning the \"lactacidemia\", it was possible to identify a stable phase of the lactate in the exercises at the treadmill and at the circuit. Conclusions: the performance of different types of exercise influences the \'VO IND.2\' and the energy expenditure during and after the exercise, while the order of the exercise practice in a single session, concerning the same metabolic answers, is just influenced in the period after the exercise. However, the total duration of the EPOC has nothing to do with the development of the different kinds of exercise, nor with the practice order. Besides, there is existence of a stable phase of the lactate in the resistance exercise, when performed in circuit.

Many cardiovascular diseases are partly due to heart muscle malfunctions. The main dynamic function in the heart is metabolism via mitochondrial respiration. And the most direct measure of oxidative tissue metabolism is the conversion rate of oxygen to water. Finding the oxygen consumption rate in the heart vessel will help us prevent the heart diseases. In the experiment, 15O-labeled RBCs (Red Blood Cells) and indocyanine green dye were injected into the isolated blood-perfused rabbit heart. The dye curves defined the inflow for the dye have the same shape as the inflow curves for the 15O oxygen. The inflow and outflow dilution curves for 15O were obtained with use of PET (Positron Emission Tomography) technology. After appropriate correction for baseline and radioactive decay, the data were transferred to a UNIX workstation for model analysis. A linear, three-region (capillary space, interstitial fluid space, and parenchymal cell space), and axially distributed model is introduced to simulate the oxygen consumption process and determine the oxygen conversion rate. Parameters of concentration are oxygen and water corresponding to capillary space, interstitial fluid space, and parenchymal cell space. The diffusion coefficients are largely independent of molecular motion. The blood flow happens only in capillary part. Other parameters are determined by experimental data. Using the input data, consumption rate is determined through a process minimizing the difference between the experimental and numerical output. Effects of key parameters on oxygen concentration and consumption rate are investigated.

O objetivo deste estudo foi investigar as contribuições dos sistemas energéticos e do gasto energético total em situação de luta. A amostra foi composta de 10 atletas do sexo masculino de nível nacional/internacional (21±6 anos; 176.2±5.3cm; 67.2±9.0kg), competindo em nível internacional. Para a estimativa das contribuições energéticas e do gasto energético total, foram realizados três protocolos simulando combate (um round, dois rounds e três rounds). As lutas foram filmadas para quantificação das ações motoras em cada round. A estimativa dos sistemas energéticos aeróbio (WAER), anaeróbio alático (WPCR) e anaeróbio lático (W[La-]) foi realizada através do consumo de oxigênio durante a atividade, do delta da concentração sanguínea de lactato de cada round e do débito alático de oxigênio (DAO2), respectivamente. A razão entre as ações de elevada intensidade e momentos de baixa intensidade (step e pausa) no protocolo 3 foi ~1:7. Os resultados dos sistemas WAER, WPCR e W[La-] no protocolo 3 foi 120±22kJ (66±6%), 54±21kJ (30±6%), 8,5kJ (4±2%), respectivamente. Assim, as sessões de treinamento devem ser direcionadas principalmente para a melhoria do sistema anaeróbio alático (responsável pelas ações de alta intensidade), e do sistema aeróbio (responsável pelo processo de recuperação entre as ações de alta intensidade) / The purpose of this study was to investigate energy system contributions and energy cost in combat situation. The sample was constituted by 10 male taekwondo athletes at national/international level (age: 21±6 years old; height: 176.2±5.3cm; body mass: 67.2±9.0kg) competing at national/international level. To estimate the energy contributions and total energy cost of the fights, athletes performed a three different protocols simulated competition (1 round, 2 rounds and 3 rounds). The combats were filmed in order to quantify the actual time spent fighting in each round. The estimate of the aerobic (WAER), anaerobic alactic (WPCR) and anaerobic lactic (W[La-]) energy systems was carried out through the oxygen consumption during the activity, the fast component of excess post-exercise oxygen consumption, and the delta of blood lactate concentration in each round, respectively. The mean data between the high intensity actions and moments of low intensity (step and pause) was ~1:7. The results of WAER, WPCR and W[La-] system contributions were 120±22kJ (66±6%), 54±21kJ (30±6%), 8,5kJ (4±2%), respectively. Thus, training sessions should be directed mainly to the improvement of the anaerobic alactic system (responsible by the high-intensity actions), and of the aerobic system (responsible by the recovery process between high-intensity)

Introdução: As adaptações fisiológicas da dança samba são pouco conhecidas. A caracterização cardiorrespiratória e metabólica aguda e/ou crônica e da composição corporal como atividade física é pouco estudada. O samba é uma atividade intermitente que envolve movimentos dos membros inferiores, tronco e membros superiores simultaneamente. Objetivo: Verificar o efeito da dança samba na aptidão cardiorrespiratória e na composição corporal de mulheres passistas que desfilam em escolas de samba. Métodos: Participaram do estudo 26 mulheres, entre 20 e 40 anos de idade, distribuídas em dois grupos: Grupo-Passistas (GP): 13 passistas de uma escola de samba tradicional de São Paulo e Grupo-Controle (GC): 13 mulheres que não dançavam samba. Foram avaliadas as funções cardiovascular e metabólica pelo teste ergoespirométrico computadorizado e a composição corporal pelas dobras cutâneas. Foram realizadas sessões de ensaio de samba não padronizadas, sendo três sessões semanais, com duração de 60 minutos, por um período de 12 semanas. A frequência cardíaca (FC) variou durante os ensaios de 66% a 85% da FCmax atingida no teste de esforço e foi monitorada por cardiofrequencímetro. Resultados: Com a prática da dança samba houve aumento de 19% no VO2max e de 13% no PO2max (P < 0,001). Houve aumento da FC no pico do esforço de 3% (P < 0,022), da RERmax em 10% (P < 0,001). A massa magra aumentou um quilo (P < 0,004), a massa gorda diminuiu 12% (P < 0,001) e a porcentagem de gordura diminuiu 11% (P < 0,001). Conclusão: Houve melhora em todos os indicadores de aptidão cardiorrespiratória e de composição corporal com 12 semanas de dança samba. Estes resultados fornecem evidências adicionais de que esse estilo de dança tem efeitos significativos para a saúde / Introduction: The physiological adaptations of samba dance aren´t well known. Cardiopulmonary characterization and acute metabolic and/or chronic, body composition and physical activity are understudied. Samba is an intermittent activity that involves movements of lower body, trunk and upper body simultaneously. Objective: To determine the effect of samba dance in cardiorespiratory fitness and body composition of women dancers who parade in samba schools. Methods: The study included 26 women aged 20 to 40 years old, divided into two groups, Women Dancers Group: 13 dancers from a traditional samba school in Sao Paulo and Control Group: 13 women who did not dance samba. Cardiovascular and metabolic functions by computerized ergospirometry and body composition by skinfold were evaluated. Samba practice sessions were held nonstandard, three weekly sessions, lasting 60 minutes, for a 12 week period. The heart rate (HR) varied during the rehearsals of 66% to 85% HRmax achieved in the stress test and was monitored for heart rate monitor. Results: The practice of dance samba increased by 19% VO2max and 13% of PO2max (P < 0,001). There were HR increase in peak stress of 3% (P < 0,022) and RERmax by 10% (P <0,001). Lean body mass increased by one kilogram (P < 0,004), fat mass decreased by 12% (P < 0,001) and fat percentage decreased by 11% (P < 0,001). Conclusion: There was improvement in all indicators of cardiorespiratory fitness and body composition with 12 weeks of samba dance. These results provide further evidence that this dance style has significant health effects

Background: Children with complex congenital heart disease (CHD) are exposed to cyanosis from birth until their surgical repair and are often not expected to participate in physical activities to the same extent as healthy peers because of a limited maximal exercise capacity (V̇O2max). Despite limitations in V̇O2max, these children may still have the capacity to perform most daily physical activity because it requires only a submaximal effort. The purpose of this research was to examine the relationships between submaximal exercise capacity, daily physical activity and cyanosis exposure, in children with complex CHD. Methods: Children with a single functioning ventricle (Fontan), tetralogy of Fallot or transposition of the great arteries, 10 to 17 years old were deemed eligible. The Bruce treadmill protocol with breath-by-breath analysis of oxygen consumption was used to assess submaximal exercise capacity. Five measures of submaximal exercise capacity were evaluated: energy consumption (V̇O2) at the ventilatory threshold, V̇O2 at a heart rate of 130 beats per minute (bpm), metabolic equivalents (METs) at ventilatory threshold, METs at 130 bpm and heart rate at stage 1 of the Bruce protocol. Moderate-to vigorous physical activity (MVPA) was measured (Actical accelerometer with 15 second epochs) for 7 consecutive days. Exposure to cyanosis was calculated by subtracting the child’s date of birth from the date of surgical repair. Results: Participants were children with a Fontan single ventricle (n=5), tetralogy of Fallot (n=4) or transposition of the great arteries (n=7). Daily physical activity was positively associated with V̇O2 at ventilatory threshold (r = 0.78, n = 16, p = < 0.01) and V̇O2 at a heart rate of 130 bpm (r = 0.61, n = 16, p = 0.01). Children who did more than 60 minutes of physical activity per day (n=4) achieved significantly higher energy expenditure before reaching ventilatory threshold, (95% CI of the difference [8.23, 24.85], t(14) = 4.27, p = < 0.01) and at a heart rate of 130 bpm (95% CI of the difference [1.61, 14.33], t(14) = 2.69, p = 0.02). Lastly, V̇O2 at ventilatory threshold was negatively associated with days spent in cyanosis (r = .55, n = 16, p = 0.03), Conclusion: Higher V̇O2 at ventilatory threshold and V̇O2 at a heart rate of 130 bpm was associated with more daily minutes spent in moderate-to-vigorous physical activity. These results suggest that children who meet the recommended 60 minutes of MVPA would have a higher submaximal exercise capacity (V̇O2 at ventilatory threshold or a heart rate of 130 bpm), than children who did not meet the MVPA guidelines. Lastly, children who were exposed to cyanosis for a longer period of time had a lower submaximal V̇O2 at ventilatory threshold, than children who were exposed to cyanosis for a shorter period of time.