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A gênese de diversas doenças cardiovasculares tem sido associada ao menor controle cardiovascular e ao desequilíbrio redox. A Variabilidade da Frequência Cardíaca (VFC) tem se mostrado eficiente em identificar alterações na função neurocardíaca causadas possivelmente pelo estresse oxidativo (EO). Poucas intervenções isoladas são capazes de promover modificações na função neurocardíaca e no balanço redox ao mesmo tempo, um exemplo é o exercício físico. Desse modo, o presente estudo tem como objetivo verificar no atual estado da arte, as relações existentes entre a função neurocardíaca e o balanço redox, além de verificar na literatura contemporânea, indicativos sobre o papel do exercício físico no balanço redox e função autonômica. É razoável inferir que existe uma razão de proporção inversa entre a VFC e o EO. Desse modo, a VFC pode ser um método não invasivo de prognóstico do EO. ABSTRACT Association between heart rate variability and oxidative stress: the role of physical exercise The genesis of cardiovascular disease has been associated with the autonomic dysfunction and redox imbalance. The heart rate variability has been efficient in identifying changes in neurocardiac function that may be caused by oxidative stress. Few isolated interventions are able to modify neurocardiac function and redox balance at same time, one example is physical exercise. Thereby, the aim of the study is to assess the association between redox balance with heart rate variability, and assess the role of physical exercise on redox balance and neurocardiac function. It is possible that HRV and oxidative stress are inversely proportional. Thus, HRV can be a non-invasive prognostic tool of oxidative stress.

Objetivo: avaliar o consumo alimentar de adolescentes praticantes de treinamento resistido ao longo de 12 semanas e sua possível influência na composição corporal. Materiais e métodos: Fizeram parte da amostra 12 sujeitos de ambos os sexos, com média de idade 17,17 anos ± 0,72. A composição corporal foi mensurada utilizando o software Terra Azul da Physical Test® versão 4.21 no qual a predição de gordura de foi feita de acordo com o protocolo de Pollock de sete dobras (pré e pós-treinamento resistido). O comportamento alimentar foi avaliado por meio do Questionário de Frequência de Consumo Alimentar - QFCA. Resultados: Os achados do nosso estudo mostraram que no período de 12 semanas de TR não houve modificação na composição corporal dos adolescentes, a estatura média foi de 1,67 m ± 0,08; da massa corporal foi de 59,87 kg ± 10,79; e do percentual de gordura de 19,62% ± 4,66; percentual da massa livre de gordura de 80,38% ± 4,66 (P>0,05). Além disso, a avaliação do estado nutricional apontou que a maioria dos adolescentes está com o consumo “abaixo do ideal” para os grupos alimentares da base da PA e “acima do ideal” para os grupos alimentares do ápice (P0.05). Moreover, the nutrition status evaluation showed that teenagers had “below-ideal” consumption of the base food groups from the food pyramid and “above-ideal” of the apex food groups from the food pyramid (P>0.05), which characterized a food pyramid inversion. Conclusion: the resistance training per se wasn’t able to modify teenagers’ body composition after 12 weeks of resistance training.

Abstract AIMS To assess the influences of sex and exercise mode on post-exercise Blood pressure (BP) immediately after exercise and during daily work. METHODS 20 healthy adults (9F/11M), randomly underwent three experimental sessions prior to their work routine: RE- Circuit resistance exercise at 40% of 1RM, AE- Aerobic exercise at 60-70% of heart rate (HR) reserve and CON- Control session. BP was assessed before and along the 1st hour of the post-intervention period (i.e. laboratory phase), and intermittently for 9h in the workplace. Results: RE promoted great BP reductions, but only in men, and this reduction persisted along the daily work (Men-RE: SBP= -1069±695 mmHg.540min; DBP= -612±325 mmHg.540min). On the other hand, AE produced slight DBP reduction in men during daily work (Men-AE: DBP= -241±730 mmHg.540min), and in women only in the laboratory phase (Women-AE: SBP= -108±65mmHg.60min). CONCLUSION Resistance exercise promotes a significant positive impact on BP in men but does not seem to be effective for women. On the other hand, AE produces moderate BP reductions in men and women.

This study aimed to compare the effects of dynamic (DRT) and isometric (IRT) resistance training on blood glucose, muscle redox capacity, inflammatory state, and muscle strength and hypertrophy. Fifteen 12-week-old male Wistar rats were randomly allocated into three groups: control group (CTL), DRT, and IRT, n = 5 animals per group. The animals were submitted to a maximal weight carried (MWC; every 15 days) and maximum isometric resistance (MIR; pre- and post-training) tests. Both training protocols were performed five times a week during 12 weeks, consisting of one set of eight uninterrupted climbs for 1 min with a 30% overload of MWC. The animals in the IRT group remained under isometry for 1 min. The DRT group experienced greater MWC from pre- to post-training compared to the CTL and IRT groups (p < 0.0001). The DRT and IRT groups displayed similar gains in MIR (p = 0.3658). The DRT group exhibited improved glycemic homeostasis (p = 0.0111), redox (p < 0.0001), and inflammatory (p < 0.0001) balance as compared with CTL and IRT groups. In addition, the improved glycemic profile was associated with an increase in muscle strength and hypertrophy, improvement in redox balance and inflammation status. We conclude that DRT was more effective than IRT on increasing cross-sectional area, but not muscle strength, in parallel to improved blood glucose, inflammatory status, and redox balance.

Introdução: A análise dos diversos fatores genéticos, principalmente os relacionados aos polimorfismos de DNA, têm sido investigados na busca de uma melhor compreensão dos mecanismos relacionados à hipertrofia e força muscular. Dentre os diversos genes polimórficos relacionados ao tema estão a miostatina e o gene α-actinina-3 (ACTN3). Objetivo: Avaliar a modulação do gene da miostatina na hipertrofia muscular esquelética e do gene ACTN3 na regulação dos níveis de força. Métodos: Estudo de revisão integrativa no qual foram pesquisados artigos que tivessem avaliado a modulação genética da hipertrofia muscular esquelética e da força. Fizeram parte desta investigação estudos originais e de revisão, publicados em português, inglês e espanhol, entre os anos de 1995 a 2017, selecionados nas bases de dados SciELO e Pubmed, utilizando-se três conjuntos de intersecção de termos de busca bibliográfica em português: a) “miostatina” e “hipertrofia muscular esquelética” e/ou “genética”; e b) “exercício físico” ou “treinamento aeróbico” ou “treinamento de força” ou “rendimento esportivo” e “ACTN3” e/ou “força muscular” e/ou genética. Em inglês: a) “myostatin”and “skeletal muscle hypertrophy” and/or genetics; and b) “physical exercise” and “aerobic training”, strength training, sports performance) and “ACTN3” “muscular strength” and/or “genetic”. E em espanhol: “miostatina” y “hipertrofia muscular esquelética” y/o genética; y b) “ejercicio físico” o “entrenamiento aeróbico” o “entrenamiento de fuerza” o “rendimiento desportivo) y “ACTN3” o “fuerza muscular” y/o genética”. Resultados e Discussão: Os estudos apontaram: a) associação do genótipo RR577 do ACTN3 com a força e o tamanho da área de secção transversa do músculo esquelético; b) correlação do alelo R com fibras glicolíticas de contração rápida e níveis médios de testosterona significativamente mais elevados; e c) o polimorfismo do ACTN3 está relacionado ao treinamento de alta intensidade. As evidências apontaram que a miostatina atua na inibição da hipertrofia muscular esquelética, e também pode ser modulada geneticamente pelo exercício físico. Conclusão: A literatura aponta evidências de que o polimorfismo do ACNT3 está relacionado com o treinamento de alta intensidade, ressaltando que, segundo os resultados dos estudos, houve correlação do alelo R, com fibras glicolíticas de contração rápida e com os níveis de testosterona significativamente mais elevados. Sendo assim, o gene ACTN3 está correlacionado com o desenvolvimento da força muscular e a folistatina, proteína antagônica da miostatina, está associada ao aumento da massa muscular. Genetic Modulation of Myostatin and Actn3 Gene in Muscular Hypertrophy and Force: an Integrative Review Introduction: The analysis of several genetic factors, especially those related to DNA polymorphisms, has been investigated in the search for a better understanding of the mechanisms related to hypertrophy and muscle strength. Among the several polymorphic genes related to the subject are myostatin and ACTN3. Objective: To evaluate the modulation of the myostatin gene in skeletal muscle hypertrophy and the ACTN3 gene in the regulation of strength levels. Methods: An integrative review study in which articles were searched that assessed the genetic modulation of skeletal muscle hypertrophy and strength. Original and review studies, published in Portuguese, English and Spanish, between 1995 and 2017, selected in the SciELO and PubMed databases, were carried out using three sets of intersection of bibliographic search: In English: a) “myostatin” and “skeletal muscle hypertrophy” and/or genetics; and b) “physical exercise” and “aerobic training”, strength training, sports performance) and “ACTN3” “muscular strength” and/or “genetic”. In Portuguese: a) “miostatina” e “hipertrofia muscular esquelética” e/ou “genética”; e b) “exercício físico” ou “treinamento aeróbico” ou “treinamento de força” ou “rendimento esportivo” e “ACTN3” e/ou “força muscular” e/ou genética. And in Spanish: “miostatina” y “hipertrofia muscular esquelética” y/o genética; y b) “ejercicio físico” o “entrenamiento aeróbico” o “entrenamiento de fuerza” o “rendimiento desportivo) y “ACTN3” o “fuerza muscular” y/o genética”. Results and Discussion: Studies indicated: a) association of RR577 genotype of ACTN3 with the strength and size of the cross-sectional area of skeletal muscle; b) correlation of the R allele with fast contracting glycolytic fibers and significantly higher mean levels of testosterone; and, c) ACTN3 polymorphism is related to high intensity training. Evidence has pointed out that myostatin acts on inhibition of skeletal muscle hypertrophy, as well as being genetically modulated by physical exercise. Conclusion: The literature showed evidence that the ACNT3 polymorphism is related to the high intensity training, emphasizing that according to the results of the studies, there was a correlation of the R allele with fast contracting glycolytic fibers and with testosterone levels higher. Thus, the ACTN3 gene is correlated with the development of muscle strength and follistatin, an antagonistic protein of myostatin, is associated with increased muscle mass. Keywords: hypertrophy, muscle strength, myostatin, polymorphism.

AbstractThe purpose of this study was to compare the effect of a combined exercise session performed at different periods of the day on the 24h blood pressure (BP) response. Anaerobic threshold (AT) and 12 repetition maximum (12RM) tests were evaluated in nine Brazilian jiu-jitsu athletes (male) (22±3.7 y; 176±5.0 cm; 73.4±9.7 kg; 6.8±2.1 % body fat). Four experimental sessions were performed: resistance exercise followed by aerobic exercise [Morning (MornS) and Afternoon (AfternS)] and Control (C) [Morning and Afternoon]. The morning sessions were conducted at 09:00 a.m. and the afternoon sessions were conducted at 3:00 p.m. The resistance exercise consisted of three sets at 90% of a 12RM for six resistance exercises. The aerobic exercise consisted of 15min at 90% of the AT. Blood pressure (BP) was measured before, during and 1h (Microlife(r) BP3A1C) after the performance of exercises in laboratory, and then during daily activities for the succeeding 23h by ambulatory BP monitoring (Dyna-MAPA(r)). Analysis of the area under the curve (AUC) indicated significant reductions in blood pressure parameters at various time points during the 24h monitoring period. For systolic BP (SBP), significantly lower values were shown following the morning session versus the control (MornS: 1756.2±100.8 vs. C: 1818.2±84.3 mmHg*15h; p < .05) and total-24h (MornS: 2695.8±143.3 vs. C: 2784.1±143.2 mmHg*24h; p < .05). The total-24h mean BP (MAP) was also significantly lower following the morning session versus the control (MornS: 2015.7±121.2 vs. C: 2087.3±153.8 mmHg*24h; p < .05). There were significant differences in the sleeping AUC of SBP (AfternS: 883.6±27.0 vs. C: 965.2±67.9 mmHg*9h; p< .05), diastolic BP (DBP) (AfternS: 481.4±30.9 vs. MornS: 552.9±34.2 and C: 562.1±52.3 mmHg*9h; p < .01) and MBP (AfternS: 651.9±22.4 vs. MornS: 708.7±43.1 and C: 726.9±64.7 mmHg*9h; p < .01). The combined exercise performed at different periods of the day contributed distinctly to the reduction of BP. The morning session was important in reducing SBP and MBP in the total-24h monitoring, while the afternoon session reduced SBP, DBP and MBP during sleeping in jiu-Jitsu athletes.

In order to investigate the validity of critical velocity (CV) as a noninvasive method to estimate the lactate minimum velocity (LMV), 25 youth runners underwent the following tests: 1) 3,000m running; 2) 1,600m running; 3) LMV test. The intensity of lactate minimum was defined as the velocity corresponding to the lowest blood lactate concentration during the LMV test. The CV was determined using the linear model, defined by the inclination of the regression line between distance and duration in the running tests of 1,600 and 3,000m. There was no significant difference (p=0.3055) between LMV and CV. In addition, both protocols presented a good agreement based on the small difference between means and the narrow levels of agreement, as well as a standard error of estimation classified as ideal. In conclusion, CV, as identified in this study, may be an alternative for noninvasive identification of LMV.

For any triathlon distance (short, Olympic, half-distance and full-distance), competitors spend more time cycling than swimming or running, but running has emerged as the discipline with the greatest influence on overall performance at the Olympic distance. However, there is a lack of evidence on which discipline has the greatest influence on performance in the overall full-distance triathlon (3.8 km swimming/180 km cycling/42.195 km running), especially for the fastest performing athletes of all time. The total race times of 51 fastest triathletes (sub-8-hour) were studied, while for the split times, a sample of 44 participants was considered. The discipline that seemed to better predict total race time was cycling (coefficient = 0.828; p < 0.001), followed by running (coefficient = 0.726; p < 0.001) and swimming (coefficient = 0.476; p < 0.001). Furthermore, cycling was the discipline with the highest performance improvement over the years, whereas running had a slightly decrease. In conclusion, cycling seems to be the discipline with greater influence in final result for the full-distance triathlon.

The aim of this study was to verify the reliability of selected variables during Wingate anaerobic test, physiologic markers and perceptual associated in trained cyclists. Fifteen male cyclists performed three tests, with workload of 0.087 times the body mass. Measures of peak power, average power, minimum power, fatigue index, heart rate, perceived effort and lactate concentration were collected. It was verified data normality, applied ANOVA One Way repeated with Tukey as post-hoc test, intraclass coefficient correlation and Bland Altman test. Results showed no significant different for the peak power, fatigue index, lactate concentration, heart rate and perceived effort between tests. Of these, peak power, heart rate and perceived effort high and significant intraclass correlation scores were found (.797−.975). Also, peak power showed good agreement between tests. In conclusion, the Wingate anaerobic test showed high reliability for peak power, heart rate and perceived effort in recreational cyclists.

The purposes of this study were to analyze and compare the effects of exercise performed in different intensities, above and below lactate threshold (LT) on post-exercise blood pressure (BP) and nitric oxide (NO) responses in individuals with type 2 diabetes (T2D). For this, 11 T2D underwent the following sessions: 1) control session; 2) 20-min of moderate cycling (80% LT); and 3) 20-min of high intensity cycling (120%LT) on a cycle ergometer. Plasma NO and BP measurements were carried out at rest and at 15 and 45 min of post-sessions. When compared to rest, only the exercise session performed at 120%LT elicited an increase of NO (from 7.2 to 9.5 µM, p

As doenças cardiovasculares (DCVs) estão entre as principais causas de morte no mundo e os processos patológicos associados com o seu desenvolvimento têm início na infância. O objetivo do estudo foi analisar e comparar as respostas de variáveis cardiovasculares durante e após a prática de vídeo game interativo e televisão. A amostra foi composta de oito crianças saudáveis (9,8 ± 0,5 anos; 30,1 ± 3,4kg; 133,3 ± 13,6 cm; 17,4 ± 4,7 kg/m²). O estudo consistiu de três sessões das quais a 1ª destinou-se a avaliação antropométrica e familiarização (FAM) com os equipamentos e o laboratório, e as demais sessões foram realizadas em ordem randomizada, sendo 30 minutos de Dance Dance Revolution (DDR), nível iniciante; e 30 minutos de televisão (TV) em que dois desenhos infantis (Ben 10 e Bob Esponja) foram apresentados. Durante as sessões foram aferidas a freqüência cardíaca (FC), Pressão Arterial Sistólica (PAS) e Pressão Arterial Diastólica (PAD) aos 10 minutos de repouso sentado, bem como aos 10, 20 e 30min de atividade (DDR ou TV) e aos 2, 10, 20, 30 e 40 min após finalização das atividades. Para a análise estatística foi verificada a distribuição normal dos dados pelo teste de Kolgomorov-Smirnov, ANOVA one-way, com Post Hoc de Scheffé para comparação entre sessões e ANOVA para medidas repetidas na comparação entre os momentos de cada sessão que foram testados. O nível de significância adotado foi p≤0,05 (ESTATÍSTICA 6.0). Aumento significativo dos valores de FC, PAS e PAM durante o DDR (30 min: 110 bpm, 116 e 89 mmHg) foram observados quando comparados com a TV (30 min: 86 bpm, 102 e 70 mmHg) respectivamente. Foi observada uma tendência de queda da FC e PAS aos 40 min de recuperação após sessão DDR, bem como uma tendência de elevação da FC, PAS, PAD e PAM após TV quando comparadas ao repouso, porém estas não foram significantes (p>0,05). Concluímos que o vídeo game interativo DDR pode ser uma alternativa interessante para aumentar o nível de atividade física, podendo trazer benefícios cardiovasculares pós-exercício. Caso estes valores de PAS se mantenham inferiores nessas crianças ao longo do dia, podemos considerar o uso desse instrumento na proteção cardiovascular durante a infância, podendo impactar positivamente na atenuação de eventos cardiovasculares na idade adulta futura, o que seria muito importante para a saúde pública.

Introduction: The anaerobic power can be defined as the maximum energy released per unit time for this system, while the anaerobic capacity can be defined as the full amount of energy available in the system. The characteristics of the development of anaerobic power and capacity in soccer players have not been elucidated. Objective: Evaluate and compare the power and anaerobic capacity in soccer players of the basic categories, sub15, sub 17, sub 20 and adult athletes that play in professional football club. Methodology: The sample consisted of 197 male soccer players, divided by category vying for championships: Group Sub 15 (n = 42), Group Sub 17 (n = 41), Group Sub 20 (n = 86); Group Adult (n = 28). To determine the parameters of power and capacity anaerobic subjects performed the Wingate Test. Results: the results allowed for the conclusion that in soccer players the maximum anaerobic power is dependent on the chronological age until the adult category, since the anaerobic capacity was dependent until the age of 20 sub category. The maximum relative anaerobic power was higher in the category under 20, but there was a decline of this variable in the adult category.

Este estudo analisou as respostas de pressão arterial sistólica (PAS) e pressão arterial diastólica (PAD) após duas sessões de exercício concorrente realizado em diferentes ordens [aeróbio-força (AF), e força-aeróbio (FA)]. Quinze indivíduos normotensos foram submetidos a duas sessões de exercício realizadas em dias distintos na seguinte sequência AF e FA. A PAS e PAD foram medidas antes e a cada 15 min durante 60 min de recuperação pós-exercício. Houve hipotensão pós-exercício (HPE) para PAS, aos 30 min (-7,4 mmHg), 45 min (-12,14 mmHg) e 60 min (-15,14 mmHg) de recuperação na sessão AF. Já na FA houve HPE apenas aos 60 min (-8,34 mmHg) de recuperação. A variação da PAS e PAD entre as sessões revelou HPE maior aos 15 min, 45 min e 60 min na PAS; e aos 45 min na PAD comparando-se AF a FA. A realização de exercício aeróbio antes do de força resultou em maior HPE para adultos jovens.The study analyzed systolic (SBP) and diastolic (DBP) blood pressure after two exercise bouts of concurrent exercise performed in a different order [aerobic-strength (AS), and strength-aerobic (SA)]. Fifteen normotensive subjects were submitted to two exercise bouts performed in different days in the following order: AS and SA. SBP and DBP were measured before and at each 15 min over a 60 min period of post-exercise recovery. Post-exercise hypotension (PEH) was found in SBP at the 30th (-7.4 mmHg), 45th (-12.14 mmHg) and 60th min (-15.14 mmHg) after AS when compared to rest. On SA, PEH was only observed at the 60th min (-8.34 mmHg) of recovery. The analysis of differences for SBP and DBP between both sessions showed greater PEH at the 15th, 45th, and 60th min in SBP; and at the 45th min in DBP after AS when compared to SA. Thus, performing aerobic before strength exercise elicited a higher PEH in young adults.

The aim of the present study was to evaluate under morphoquantitative aspects possible alterations in the ascending section of the Aorta’s endothelium of elderly Wistar rats (16 months of age) trained at an anaerobic threshold intensity. Ten male animals were divided in two experimental groups (control and exercise, each with 5 animals). The exercise group performed swimming five times per week, 30 minutes per day during eight weeks. Anaerobic threshold was evaluated at the first, fourth and eighth week of training. After the intervention the animals were sacrificed and the heart and Aorta were collected. The Aorta was properly fixed and prepared according to the histology procedures for coloring with Hematoxilin-Eosin, Weigert and Verhoeff. Quantitative and qualitative evaluations were performed using morphometric and stereological methods. There was an increase in the thickness, cross sectional area, elastic fibers and distance between the beams and the nucleus of the smooth muscle without alteration of its diameter (p< .05).

Introdução: O protocolo de lactato mínimo (LM) é precedido de um esforço máximo para indução a hiperlactatemia. Objetivo: Verificar a reprodutibilidade de um teste de LM com indução à hiperlactatemia realizada em teste incremental com cargas individualizadas através da percepção subjetiva de esforço (PSE). Metodologia: A amostra foi composta por 20 estudantes fisicamente ativos (25,4 ± 4,1 anos; 14,1 ± 5,0 % gordura), submetidos a dois testes de LM com metodologia idêntica. A indução a hiperlactatemia foi realizada por um teste com quatro estágios, com duração de três minutos cada e cargas individualizadas pela PSE (níveis 10, 13, 16 e o último estágio 17-20 até a exaustão voluntária). Após oito minutos de recuperação o teste progressivo começou com carga inicial de 75 W e incrementos de 25 W a cada três minutos, até a exaustão. Resultados: As intensidades de LM 1 (155,0 ± 23,8 W) e LM 2 (157,5 ± 27,0 W) não diferiram estatisticamente (p = 0,795) e de uma maneira geral apresentaram boa reprodutibilidade (CCI = 0,79) e concordância [-2,5 W de média da diferença e ± 41,8 W de abas]. Conclusão: O teste de LM, com cargas para hiperlactatemia individualizadas pela PSE, se mostrou reprodutível em indivíduos fisicamente ativos.The lactate minimum protocol (LM) is preceded by a maximum effort to induce hyperlactatemia. Objective: To verify the reliability of LM test with induced hyperlactatemia realized by exercise intensity individualized by the rating perceived effort (RPE). Methods: The sample was composed of 20 students, physically active (25.4 ± 4.1 years, 14.1 ± 5.0% fats) who were undertaken to two tests with identical methodology of LM. Induction of hyperlactatemia was performed by a test with four stages, lasting three minutes each, loads individualized by the PSE (levels 10, 13, 16 and 17-20 last stage until voluntary exhaustion). After eight minutes of recovery the progressive test started with initial load of 75W and 25W increments every 3 min until exhaustion. Results: The intensities of LM 1 (155.0 ± 23.8 W) and 2 (157.5 ± 27.0 W) did not differ statistically (p = 0.795) and showed good reliability (ICC = 0.79) and agreement [-2.5 W of mean difference and ± 41.8 W of bias]. Conclusion: The LM test, with loads for induction of hyperlactatemia individualized by the RPE, has shown to be reliable in physically active individuals.

Severe obesity affects metabolism with potential to influence the lactate and glycemic response to different exercise intensities in untrained and trained rats. Here we evaluated metabolic thresholds and maximal aerobic capacity in rats with severe obesity and lean counterparts at pre- and post-training. Zucker rats (obese: n = 10, lean: n = 10) were submitted to constant treadmill bouts, to determine the maximal lactate steady state, and an incremental treadmill test, to determine the lactate threshold, glycemic threshold and maximal velocity at pre and post 8 weeks of treadmill training. Velocities of the lactate threshold and glycemic threshold agreed with the maximal lactate steady state velocity on most comparisons. The maximal lactate steady state velocity occurred at higher percentage of the maximal velocity in Zucker rats at pre-training than the percentage commonly reported and used for training prescription for other rat strains (i.e., 60%) (obese = 78±9% and lean = 68±5%, P 0.05), whereas increase in maximal velocity was greater in the obese group (P

Post-exercise hypotension (PEH) is characterized by a decrease in blood pressure (BP) in relation to pre-exercise levels and has been intensively studied in different populations after different modes of exercise. Several mechanisms are associated with PEH, which makes it a multifactorial condition. However, over the last decade, some studies aimed to investigate the possible influence of ethnic and genetic factors on PEH. Thus, the purpose of this study was to review the environmental and, mainly, ethnic and genetic factors related to PEH. The studies used herein were obtained from a review of the following online databases: MEDLINE, SciELO and, Portal Capes. In relation to ethnicity, studies appear to indicate an unfavorable trend toward development of PEH in blacks as compared to whites, although this cannot be stated categorically. As for genetic studies and PEH, we stress the importance of these studies and highlight the need for selecting candidate genes for research on the basis of the physiological system implicated in BP regulation. Published studies have basically examined the relationship between PEH and mutations in genes that express proteins involved in the renin-angiotensin-aldosterone system. In this genetic sense, it seems that the greatest decline in PA occurs mainly after low-intensity aerobic exercise performed by normotensive or borderline hypertensive adult men. Further studies on the subject are required.

A hipotensão pós-exercício caracteriza-se pela redução dos valores pressóricos em relação ao pré-exercício, sendo intensamente estudada em diferentes populações a partir das diversas modalidades de exercício físico. Inúmeros mecanismos relacionam-se à HPE, tornando-a de origem multifatorial. No entanto, na última década, alguns estudos objetivaram investigar possíveis influências de fatores étnicos e genéticos sobre a HPE. Nesse sentido, o objetivo do presente estudo foi revisar os fatores ambientais e principalmente, os étnicos e genéticos relacionados à HPE. Os estudos utilizados nesta revisão de literatura foram obtidos a partir de um levantamento bibliográfico realizado nos seguintes bancos de dados disponíveis na internet: Medline, SciELO e Portal Capes. Com relação à etnia, verifica-se que os estudos apontam desfavorável tendência aos indivíduos negros em obter HPE quando comparados aos de etnia branca, embora ainda não seja possível afirmar de maneira categórica. Quanto aos estudos genéticos e HPE, ressalta-se a importância destes estudos, assim como a necessidade de que a seleção dos genes candidatos à investigação seja feita baseando-se no sistema fisiológico implicado na regulação da PA. Basicamente, os estudos publicados analisaram a relação entre HPE e mutações de genes que expressam proteínas envolvidas no sistema renina-angiotensina-aldosterona. Nesse sentido, parece que o maior decaimento da PA ocorre, principalmente, após exercícios aeróbios de baixa intensidade realizados por homens adultos e normotensos limítrofes ou hipertensos, sendo necessários mais estudos acerca do tema.

FUNDAMENTO: O gene da enzima conversora de angiotensina (gene ECA) tem sido amplamente estudado em relação a fenótipos de aptidão cardiorrespiratória, contudo a associação do genótipo da ECA com corridas de meia-distância tem sido pouco investigada. OBJETIVO: O presente estudo investigou a possível influência da enzima conversora de angiotensina (ECA) (I/D) sobre a aptidão cardiovascular e o desempenho em corridas de meia-distância por parte de brasileiros jovens do sexo masculino. A validade da previsão de VO2max em relação ao genótipo da ECA também foi analisada. MÉTODOS: Um grupo homogêneo de homens jovens moderadamente ativos foi avaliado em um teste de corrida (V1600 m; m.min-1) e em um teste adicional em esteira ergométrica para a determinação de VO2max. Posteriormente, o [(0,177*V1600m) + 8.101] VO2max real e previsto foi comparado com os genótipos da ECA. RESULTADOS: O VO2max e V1600m registrados para os genótipos DD, ID e II foram 45,6 (1,8); 51,9 (0,8) e 54,4 (1,0) mL.kg-1.min-1 e 211,2 (8,3); 249,1 (4,3) e 258,6 (5,4 ) m.min-1, respectivamente e foram significativamente mais baixos para os genótipos DD (p < 0,05). O VO2max real e previsto não diferiram entre si, apesar do genótipo da ECA, mas o nível de concordância entre os métodos de VO2max real e estimado foi menor para o genótipo DD. CONCLUSÃO: Concluiu-se que existe uma possível associação entre o genótipo da ECA, a aptidão cardiovascular e o desempenho em corridas de média distância de jovens do sexo masculino moderadamente ativos e que a precisão da previsão do VO2max também pode ser dependente do genótipo da ECA dos participantes.BACKGROUND: The angiotensin I-converting enzyme gene (ACE gene) has been broadly studied as for cardiorespiratory fitness phenotypes, but the association of the ACE genotype to middle-distance running has been poorly investigated. OBJECTIVE: This study investigated the possible influence of Angiotensin-Converting Enzyme (ACE) genotype (I/D) on cardiovascular fitness and middle-distance running performance of Brazilian young males. The validity of VO2max to predict the ACE genotype was also analyzed. METHODS: A homogeneous group of moderately active young males were evaluated in a 1,600 m running track test (V1600m; m.min-1) and in an incremental treadmill test for VO2max determination. Subsequently, the actual and the predicted [(0.177*V1600m) + 8.101] VO2max were compared to ACE genotypes. RESULTS: The VO2max and V1600m recorded for DD, ID and II genotypes were 45.6 (1.8); 51.9 (0.8) and 54.4 (1.0) mL.kg-1.min-1 and 211.2 (8.3); 249.1 (4.3) and 258.6 (5.4) m.min-1 respectively, and were significantly lower for DD carriers (p< 0.05). The actual and predicted VO2max did not differ from each other despite ACE genotype, but the agreement between actual and estimated VO2max methods was lower for the DD genotype. CONCLUSION: It was concluded that there is a possible association between ACE genotype, cardiovascular fitness and middle-distance running performance of moderately active young males and that the accuracy of VO2max prediction may also depend on the ACE genotype of the participants.

Postexercise hypotension plays an important role in the non-pharmacological treat-ment of hypertension and is characterized by a decrease in blood pressure after a single exercise bout in relation to pre-exercise levels. This study investigated the effects of exercise intensity and creatine monohydrate supplementation on postexercise hypotension, as well as the possible role of blood lactate in this response. Ten normotensive subjects underwent resistance exercise sessions before (BC) and after (AC) creatine supplementation: 1) muscle endurance (ME) consisting of 30 repetitions at 30% of one-repetition maximum; 2) hypertrophy (HP) consisting of 8 repetitions at 75% of one-repetition maximum. Blood pressure was measured before and after the exercise bout. Blood lactate was measured after the exercise bout. The HP and ME sessions promoted a decrease in systolic blood pressure (∆ -19 ± 1.0 mmHg; ∆ -15 ± 0.9 mmHg, respectively, P< 0.05), which was attenuated after creatine supplementation (∆ -7.1 ± 1.0 mmHg; ∆ -11 ± 1.0 mmHg, respectively, P 0.05). In conclusion, resistance exercise intensity did not influence postexercise hypotension. Creatine supplementation attenuated the decrease in blood pressure after resistance exercise. The results suggest the involvement of blood lactate in post-resistance exercise hypotension.

The objectives of this study were to evaluate the validity of the lactate minimum (LM) using a ramp protocol for the determination of LM intensity (LMI), and to estimate the exercise intensity corresponding to maximal blood lactate steady state (MLSS). In addition, the possibility of determining aerobic and anaerobic fitness was investigated. Fourteen male cyclists of regional level performed one LM protocol on a cycle ergometer (Excalibur–Lode) consisting of an incremental test at an initial workload of 75 Watts, with increments of 1 Watt every 6 seconds. Hyperlactatemia was induced by a 30-second Wingate anaerobic test (WAT) (Monark–834E) at a workload corresponding to 8.57% of the volunteer’s body weight. Peak power (11.5±2 Watts/kg), mean power output (9.8±1.7 Watts/kg), fatigue index (33.7±2.3%) and lactate 7 min after WAT (10.5±2.3 mmol/L) were determined. The incremental test identified LMI (207.8±17.7 Watts) and its respective blood lactate concentration (2.9±0.7 mmol/L), heart rate (153.6±10.6 bpm), and also maximal aerobic power (305.2±31.0 Watts). MLSS intensity was identified by 2 to 4 constant exercise tests (207.8±17.7 Watts), with no difference compared to LMI and good agreement between the two parameters. The LM test using a ramp protocol seems to be a valid method for the identification of LMI and estimation of MLSS intensity in regional cyclists. In addition, both anaerobic and aerobic fitness parameters were identified during a single session.

Type 2 Diabetes mellitus (DM2) is a metabolic disease Type 2 Diabetes mellitus (DM2) is a metabolic disease characterized by hyperglycemia and cardiovascular dysfunctions that can be controlled with physical exercise, dietary control and pharmacological treatment. Recent research has demonstrated associations between DM2 and some genetic polymorphisms, especially alterations to the gene that codes for Angiotensin Converting Enzyme (ACE). The purpose of this study was to discuss the pathophysiology of DM2 and the use of physical exercise as a non-pharmacological method for controlling these patients’ glycemia and blood pressure. The relationship between DM2 and polymorphisms of the ACE gene was also covered. The literature search included textbooks in the healthcare field in addition to review articles and original articles found on the databases Pubmed, Scielo and Portal Capes. Keywords used were “blood glucose”, “type 2 diabetes”, “exercise”, “blood pressure” and “ACE gene polymorphism” and their translations in Portuguese. The main subject of this article is the practice of daily exercise, the types and intensities that have proven effective for glycemic and haemodinamic control and possible relationships with the ACE polymorphism, which are currently still tentative, since the evidence of associations can be strongly influenced by the population studied. The benefits of exercise are unquestionable and the recommended forms are discussed in this review. However the literature is still lacking studies that analyze the effects of physical exercise on diabetics and take into account the relationship with genetic aspects. This area is evidently an appropriate subject for further research.

Type 2 Diabetes mellitus (DM2) is a metabolic disease characterized by hyperglycemia and cardiovascular dysfunctions that can be controlled with physical exercise, dietary control and pharmacological treatment. Recent research has demonstratedassociations between DM2 and some genetic polymorphisms, especially alterations to the gene that codes for Angiotensin Converting Enzyme (ACE). The purpose of this study was to discuss the pathophysiology of DM2 and the use of physical exercise as a non-pharmacological method for controlling these patients’ glycemia and blood pressure.The relationship between DM2 and polymorphisms of the ACE gene was also covered. The literature search included textbooks in the healthcare field in addition to review articles and original articles found on the databases Pubmed, Scielo and Portal Capes.Keywords used were “blood glucose”, “type 2 diabetes”, “exercise”, “blood pressure” and “ACE gene polymorphism” and their translations in Portuguese. The main subject of this article is the practice of daily exercise, the types and intensities that have proven effective for glycemic and haemodinamic control and possible relationships with the ACE polymorphism, which are currently still tentative, since the evidence of associations canbe strongly influenced by the population studied. The benefits of exercise are unquestionable and the recommended forms are discussed in this review. However the literature is still lacking studies that analyze the effects of physical exercise on diabetics and takeinto account the relationship with genetic aspects. This area is evidently an appropriate subject for further research.

http://dx.doi.org/10.5007/1980-0037.2008v10n1p43 Precise estimation of oxygen uptake kinetics parameters is essential to understand its control and/or limit uptake mechanisms. The purpose of the present study was to characterize the oxygen uptake kinetics responses during supramaximal cycle ergometer exercise using two modeling techniques. Eleven male subjects (age = 25.4 ± 4.9 years, height = 177.0 ± 4.0 cm, mass = 77.1 ± 11.3 kg, VO2max = 40.3 ± 6.3 mL.kg-1.min-1) performed a series of square- have exercise transitions to exhaustion at intensities equivalent to 100, 113, 133 and 153% of VO2max. The time constant of the primary component was estimated with an exponential and semi-logarithmic model, comparisons were made using repeated measures ANOVA and the Tukey post hoc tests, with statistical signifi cance accepted when p

http://dx.doi.org/10.5007/1980-0037.2008v10n1p8 With the objective of analyzing the blood glucose responses during and after exercise performed at 90 and 110% of anaerobic threshold (AT), 10 type-2 diabetes patients (56.9±11.2years; 80.3±14.4kg) performed an incremental test (IT) on a cycle ergometer. After an initial IT to identify AT, the volunteers participated in three experimental sessions on three different days: 20 minutes’ of cycling at either 90 or 110% of AT, and a control session (CON). Blood glucose was measured at rest, and at the 10th and 20th minutes of exercise or control condition, as well as every 15 minutes during a 2-hour postexercise recovery period (Rec). One-way ANOVA did not detect significant differences in blood glucose levels between the sessions at 90 and 110% of AT. Compared to CON, a signifi cant decrease was observed at the 20th minute of exercise, and at the 15th and 60th minutes of Rec from the 90% AT session. Significant reductions were also observed at the 10th and 20th minutes of exercise and at the 15th, 30th, 45th, 60th and 90th minutes of Rec from the session at 110% AT. Exercise performed at the higher intensity (110% AT) resulted in a tendency of a more pronounced and prolonged hypoglycemic effect during and after exercise, and may be an alternative intensity for glycemic control in type 2 diabetics who do not have cardiovascular complications or other contraindications to exercising at intensities above the AT.

Precise estimation of oxygen uptake kinetics parameters is essential to understand its control and/or limit uptake mechanisms. The purpose of the present study was to characterize the oxygen uptake kinetics responses during supramaximal cycle ergometer exercise using two modeling techniques. Eleven male subjects (age = 25.4 ± 4.9 years, height = 177.0 ± 4.0 cm, mass = 77.1 ± 11.3 kg, VO2max = 40.3 ± 6.3 mL.kg-1.min-1) performed a series of square-wave exercise transitions to exhaustion at intensities equivalent to 100, 113, 133 and 153% of VO2max. The time constant of the primary component was estimated with an exponential and semi-logarithmic model, comparisons were made using repeated measures ANOVA and the Tukey post hoc tests, with statistical signifi cance accepted when p Resumo A correta estimativa dos parâmetros da cinética do consumo de oxigênio é fundamental para a interpretação de seus mecanismos de controle e/ou limitação. O objetivo deste estudo foi caracterizar a cinética do consumo de oxigênio em intensidades supra-máximas realizadas em cicloergômetro a partir da utilização de dois modelos matemáticos distintos. Onze indivíduos saudáveis do sexo masculino (idade = 25,4 ± 4,9 anos, estatura = 177,0 ± 4,0 cm, massa corporal = 77,1 ± 11,3 kg, VO2max = 40,3 ± 6,3 mL.kg-1.min-1) realizaram quatro testes retangulares exaustivos de intensidades correspondentes a 100, 113, 133 e 153%VO2max. As constantes de tempo do componente primário da cinética do VO2 foram estimadas a partir dos modelos exponencial e semi-logarítmico e comparadas através de ANOVA para medidas repetidas e post hoc de Tukey, admitindo-se P

O limiar de esforço percebido contínuo (LEPc) pode ser considerado como ponto de transição metabólica entre os domínios intenso e severo, pois se relaciona com a potência crítica. Dessa forma, os objetivos do presente estudo foram: (1) verifi car a possibilidade de estimativa do LEP e de um indicador de máximo estado estável de lactato em exercício intermitente (LEPi e MEELINDIC), (2) comparar o LEPi e MEELINDIC com o máximo estado estável de lactato intermitente (MEELi), e (3) verifi car a relação entre a PSE e as respostas de lactato sangüíneo ([La]) em esforços intermitentes de alta intensidade. Dez participantes foram submetidos a sessões de familiarização, teste de esforço progressivo, testes preditivos intermitentes e determinação do MEELi. O LEPi e o MEELINDIC foram estimados a partir dos testes preditivos, e o MEELi foi determinado a partir de testes de 30 minutos. As correlações entre as taxas de aumento da PSE e [La] (r=0,77), e os valores absolutos de PSE e [La] (r=0,78) foram moderadas. Os altos valores de R2 das taxas de aumento da PSE e [La] e das regressões lineares para a estimativa do LEPi e do MEELINDIC sugerem que essas variáveis podem ser estimadas de forma acurada. As intensidades do LEPi, MEELINDIC e MEELi não foram diferentes entre si. O LEPi e MEELINDIC apresentaram altas correlações com o MEELi (r=0,90 e r=0,80, respectivamente). Portanto, a relação entre a PSE e [La] é moderada, e tanto o LEPi quanto o MEELINDIC podem ser estimados e utilizados como indicadores de capacidade aeróbia. ABSTRACT The continuous perceived exertion threshold (PETc) is considered as a metabolic transition point between the heavy and severe domain, since it is related with critical power. Thus, the aims of this study were: (1) to verify the possibility to estimate PET and maximal lactate steady state index in intermittent exercises (PETi and MLSSINDEX), (2) compare the PETi and MLSSINDEX with intermittent exercise maximal lactate steady state (MLSSi), and (3) to verify the relationship between RPE and blood lactate response ([La]) in high intensity intermittent exercises. Ten subjects underwent familiarization sessions, progressive exercise test, predictive intermittent trials and MLSSi determination. The PETi and MLSSINDIC were estimated from predictive trials, and MLSSi was determined from 30-minute tests. The correlations between the increase rates of RPE and [La] (r=0.77), and the absolute values of RPE and [La] (r=0.78) were moderate. The high R2 values as related to the relationship between the increase rate of RPE and [La], and also to the linear regressions for the PETi and MLSSINDEX estimation suggest that these variables may be accurately estimated. The PETi, MLSSINDEX and MLSSi intensities were not different from each other. The correlations between PETi and MLSSINDEX, with MLSSi were strong (r=0.90 and r=0.80, respectively). Therefore, the relationship between RPE and [La] is moderate, while both PETi and MLSSINDEX can be estimated and utilized as aerobic capacity indicators.

The purpose of this study was to analyze the possibility of identifying the lactate minimum velocity (LM) and estimating the maximal lactate steady state intensity (MLSS) by applying a polynomial function to just three stages of the LM test. Seventeen physically active males (24.1 ± 4.0 years; 23.8 ±2.2kg.m2(-1) BMI; 11.7 ± 3.8% body fat) performed: 1) a 1600m time trial (1600mV); 2) a 150m sprint to induce hyperlactatemia, and then an incremental test (InT) consisting of 6 x 800m at intensities of 78, 81, 84, 87, 90 and 93% of 1600mV; 3) 2 to 3 sessions of constant 30 min running tests to identify MLSS. Blood lactate [lac] was determined by an electrochemical method (YSI - 2700 SELECT). The LM was identifi ed visually (LMv) as well by applying polynomial function to the [lac] responses at all 6 stages (LMp), to the 1st, 3rd and 5th stages (LMp135), to the 1st, 3rd and 6th stages (LMp136) and to the 1st, 4th and 6th stages (LMp146) of InT. The ANOVA detected no differences between the velocities (m.min-1) identifi ed by LMv (196.0 ± 17.8) LMp (198.0 ± 17.6), LMp135 (197.7 ± 17.6), LMp136 (200.0 ± 17.2), LMp146 (199,7 ± 18,1) and MLSS (198.7 ±16.6) (p>0.05), with a high correlation among each other (p RESUMO O propósito do estudo foi analisar a possibilidade de identifi cação da velocidade de lactato mínimo (LM) e de se estimar a máxima fase estável de lactato (MFEL), aplicando a função polinomial de segunda ordem a partir de apenas três estágios do teste do LM. Participaram do estudo 17 homens fi sicamente ativos (24,1 ± 4.0 anos; 23,8 ± 2,2kg.m2(-1) IMC; 11,7 ± 3,8% gordura corporal) realizaram: 1) corrida de 1600m no menor tempo possível para cálculo da velocidade média (1600mV); 2) “sprint” de 150m para indução de hiperlactatemia e um teste incremental (Tin) consistindo de 6x800m a intensidades de 78, 81, 84, 87, 90 e 93% do 1600mV; 3) 2 a 3 sessões de 30 min de corrida em intensidade constante para determinação da MFEL. O lactato sanguíneo [lac] foi determinado pelo método eletroenzimático (YSI - 2700 SELECT). O LM foi identifi cado visualmente (LMv) bem como aplicando ajuste polinomial usando todos os 6 estágios (LMp), o 1º, 3º e 5º estágios (LMp135), o 1º, 3º e 6º estágios (LMp136) e o 1º, 4º e 6º estágios (LMp146) do test incremental. ANOVA evidenciou não haver diferenças entre as velocidades (m.min-1) identifi cadas pelo LMv (196,0 ± 17,8), LMp (198,0 ± 17,6), LMp135 (197,7 ± 17,6), LMp136 (200,0 ±17,2), LMp146 (199,7 ±18,1) e MFEL (198,7 ± 16,6) (p>0,05), e alta correlação entre os métodos estudados (p

Stationary cycling tests were used to analyze the validity of methods for estimating the Maximal Lactate Steady State (MLSS) and the velocity and heart rate (HR) that are sustainable during a 40-km time trial. Methods: 11 cyclists (23.9±4.1 years; 178±6.8 cm tall; 68.8±5.4 kg) performed the following tests on a cyclosimulator, using their own bicycles: 1) Determination of the mean velocity and HR achieved during a 5-km (5kmVel and HR5km) and a 40-km time trial (40kmVel and HR40km). 2) 2-3 endurance tests to determine MLSSV with blood lactate ([lac]) measurements. The relationship between MLSSV and 5kmVel in data from Harnish et al. (2001) was also used to calculate predicted MLSSV (km•h-1): [MLSSVp = 0.8809 x 5kmVel + 1.6365]. The HR corresponding to MLSSV (MLSSHR) was estimated by taking 88% of HR5km (maximal- HR) (Swensen et al. 1999). Results: The 5kmVel, 40kmVel, MLSSV and MLSSVp were 50.07±2.03, 45.57±1.97, 45.64±2.0 and 45.77±1.77km•h-1 respectively. No differences were found between 40kmVel, MLSSV and MLSSVp. Neither did [lac] or HR corresponding to MLSSV/40kmVel exhibit differences 4.5±0.6/4.2±0.3mM and 175.1±3.0/176.8±3.1 bpm). The MLSSV was 90.9±0.5% of 5kmVel and MLSSHR was 93.6±0.5% of HR5km. Conclusion: The equation proposed is valid for estimating both MLSSV and 40kmVel on a stationary cyclosimulator. ABSTRACT A validade de se estimar a velocidade e a frequência cardíaca (FC) correspondentes ao máximo estado estável de lactato sanguíneo (MEEL), bem como a velocidade e FC que poderiam ser mantidas durante uma prova simulada de 40-km foram estudados em ciclismo estacionário. Métodos: 11 ciclistas (23,9±4,1anos; 178±6,8cm altura; 68,8±5,4kg) realizaram os seguintes testes em ciclo-simulador, utilizando suas próprias bicicletas: 1) Determinação da velocidade média e a FC correspondentes aos testes de 5-km (5kmVel e FC5km) e 40-km (40kmVel e FC40km). 2) 2-3 testes de longa duração com dosagem de lactato sanguíneo [lac] para determinação do MEEL. O MEEL (km•h-1) foi estimado (MEELe) pela relação entre os resultados de MEEL e 5kmVel publicados por Harnish et al. (2001): [VSSMLp = 0,8809 x 5kmVel + 1,6365]. A FC correspondente ao MEEL (FCMEEL) foi estimada considerando 88% da FC5km (FCmáxima) (Swensen et al. 1999). Resultados: A 5kmVel, 40kmVel, MEEL and MEELe foram 50,07±2,03, 45,57±1,97, 45,64±2,0 and 45,77±1,77km•h-1 respectivamente. Não foram encontradas diferenças entre 40kmVel, MEEL e MEELe. A [lac] e a FC correspondentes ao MEEL/40kmVel (4,5±0,6/4,2±0,3mM e 75,1±3,0/176,8±3,1bpm) não foram diferentes entre si. O MEEL ocorreu a 90,9±0,5% de 5kmVel e a FCMEEL a 93,6±0,5% de FC5km. Conclusão: A equação proposta se mostrou válida para estimar tanto o MEEL quanto a velocidade em prova de 40km no ciclismo estacionário.

The purpose of this study was to apply the two and three-parameter critical power model equations after depletion of a fi xed amount of anaerobic work capacity (AWC), followed by a short rest period. Sixteen subjects underwent: (1) two practice trials for ergometer familiarization to severe exercise; (2) 4-5 exercise bouts on different days for the estimation of critical power (CP) and AWC using the two and three parameter models; (3) the same procedures as described in stage 2 were repeated after 30 s recovery from 180 s of exercise completed at an intensity that would have elicited exhaustion in around 300 s. The CP2parameter (130-174 W versus 131-170 W) and CP3parameter (108 versus 100 W) estimated after prior severe exercise followed by a short rest period remained stable compared to the fatigue-free tests. The AWC2parameter was reduced in response to prior severe exercise. The AWC3parameter was not significantly reduced. The correlations between CP2parameter derived from the same equation with and without prior AWC2parameter reduction were strong (r = 0.97-0.99, P ABSTRACT O propósito do presente estudo foi aplicar as equações do modelo de potência crítica de dois e três parâmetros após a depleção de uma quantia fi xa de capacidade de trabalho anaeróbio (AWC), seguido de um período curto de repouso. Dezesseis sujeitos realizaram: (1) duas familiarizações ao exercício severo no cicloergômetro; (2) 4-5 exercícios máximos em dias diferentes para a estimativa da CP e AWC por meio dos modelos de dois e três parâmetros; (3) os mesmos procedimentos descritos no #2 foram realizados após 30 s de repouso e de um exercício de 180 s a uma intensidade em que a exaustão provavelmente ocorreria em ~300 s. A CP2parameter (130-174 W versus 131-170 W) e CP3parameter (108 versus 100 W) estimadas após o exercício prévio severo e seguido por um curto período de repouso permaneceu estável quando comparado às estimativas sem o exercício prévio. A AWC2parameter foi diminuída em resposta ao exercício prévio severo. A AWC3parameter não foi significativamente reduzida. As correlações entre CP2parameter derivados da mesma equação com e sem a redução prévia da AWC2parameter foram fortes (r = 0,97-0,99; P < 0,001). Para a CP3parameter a correlação foi somente moderada (r = 0,62; P = 0,01). Assim, pode ser concluído que o modelo de potência crítica de dois parâmetros promove descrições matemáticas coerentes quando é induzido um exercício prévio, sendo que a AWC2parameter foi alterada enquanto que a estimativa da CP2parameter permaneceu constante.

To compare the hypotensive effects of exercise sessions performed on treadmill and cycle ergometer and toverify the infl uence of the intensity of such exercise sessions on post-exercise hypotension (PEH). Ten normotensive malesubjects (24.9 ± 3.9 years; 78.3 ± 9.2 kg; 176.9 ± 4.9 cm) performed 4 exercise sessions on different days: two incrementalexercise sessions on a cycle ergometer and a treadmill running until volitional exhaustion, and two continuous exercisesessions (20 min) on a cycle ergometer and a treadmill at intensities corresponding to 85% of maximal heart rate (max HR)reached during the incremental tests. Systolic (SBP) and diastolic blood pressure (DBP) were measured on resting, at theend of exercises and during the 90 minute post-exercise recovery period. After the incremental and continuous sessions onthe treadmill SBP presented a signifi cant reduction at the 45th and 90th minutes and DBP was reduced throughout the entirepost-exercise recovery period (P < 0.05). Post-exercise SBP hypotension was observed at the 90th min of recovery from theincremental and continuous exercise sessions performed on the cycle ergometer, whereas post-exercise DBP hypotensionwas only observed at the 90th minute of recovery from the continuous submaximal session (p < 0.05). Exercise in the form ofrunning on the treadmill was more effective for inducing PEH than exercise performed on the cycle ergometer. The exerciseintensities studied did not appear to infl uence PEH either after treadmill running or cycle ergometer sessions. RESUMO O estudo teve como objetivo comparar os efeitos hipotensores de sessões de exercícios realizados em esteiraergométrica e cicloergômetro e verifi car a infl uência da intensidade dessas sessões sobre a hipotensão pós-exercício(HPE). Participaram do estudo 10 indivíduos normotensos do sexo masculino (24,9 ± 3,9 anos; 78,3 ± 9,2 kg; 176,9 ± 4,9cm) executaram 4 sessões de exercícios em dias distintos: dois testes incrementais em cicloergômetro e corrida em esteiraergométrica até a exaustão voluntária, e duas sessões de exercício contínuo (20 min) em cicloergômetro e esteira à 85%da freqüência cardíaca máxima (FC máx.) atingida nos testes incrementais. A pressão arterial sistólica (PAS) e diastólica(PAD) foram mensuradas em repouso pré-exercício, ao fi nal dos exercícios e durante 90 min de recuperação pós-exercício.Em relação aos valores de repouso pré-exercício, após as sessões de exercício incremental e contínuo em esteira aPAS se apresentou signifi cativamente reduzida (p < 0,05) aos 45 e 90 min, enquanto a PAD se apresentou diminuída (p< 0,05) durante todo o período de recuperação pós-exercício. Após as sessões de exercício incremental e contínuo emcicloergômetro, observou-se HPE de PAS aos 90 min de recuperação, enquanto que HPE de PAD foi observada aos 90min de recuperação apenas após sessão contínua submáxima (p < 0,05). Concluiu-se que o exercício realizado em esteirafoi mais efi caz que o exercício em cicloergômetro em induzir HPE. As intensidades de exercício empregadas nesse estudoparecem não exercer infl uência na HPE realizado em esteira e em cicloergômetro.

The present study aimed to verify if blood pressure (BP) reactivity could be reduced through a previous single session of active playing when compared to sedentary leisure. Sixteen pre-pubertal healthy children participated in this study. After familiarization with procedures and anthropometric evaluation, participants performed three sessions in randomized order: 1) 30 min of traditional Brazilian games (PLAY); 2) 30 min of video game playing (DDR); and 3) 30 min of watching TV (TV). Each session lasted ~80 minutes, being 10 min of rest; 30 min of intervention activity; and 40 min of recovery. After recovery, the Cold Pressor Test (CPT) was used for the assessment of acute cardiovascular reactivity. Blood Pressure (BP) was recorded at 30 s and 1 min during the CPT. Analysis of variance showed post-exercise hypotension (PEH) only after PLAY, and that systolic and diastolic BP were significantly increased in all conditions during CPT. However, the magnitude of the CPT-induced blood pressure response was significantly less in PLAY compared to DDR and TV. The PEH observed during recovery and the reduced BP response to CPT following playing traditional games may be due its higher cardiovascular and metabolic demand as was indicated by the increased heart rate, oxygen consumption, and blood pressure. It was concluded that BP reactivity to stress may be reduced through a previous single session of traditional games and that PEH was recorded only after this exercise form. This benefit indicates a potential role of playing strategies for cardiovascular health in childhood.

This study compared the plasma kallikrein activity (PKA), bradykinin concentration (BK), DesArg(9)-BK production, nitric oxide release (NO) and blood pressure (BP) response after moderate-intensity aerobic exercise performed by individuals with and without type 2 diabetes. Ten subjects with type 2 diabetes (T2D) and 10 without type 2 diabetes (ND) underwent three sessions: 1) maximal incremental test on cycle ergometer to determine lactate threshold (LT); 2) 20-min of constant-load exercise on cycle ergometer, at 90% LT and; 3) control session. BP and oxygen uptake were measured at rest and at 15, 30 and 45 min post-exercise. Venous blood samples were collected at 15 and 45 minutes of the recovery period for further analysis of PKA, BK and DesArg(9)-BK. Nitrite plus nitrate (NOx) was analyzed at 15 minutes post exercise. The ND group presented post-exercise hypotension (PEH) of systolic blood pressure and mean arterial pressure on the 90% LT session but T2D group did not. Plasma NOx increased ~24.4% for ND and ~13.8% for T2D group 15 min after the exercise session. Additionally, only ND individuals showed increases in PKA and BK in response to exercise and only T2D group showed increased DesArg(9)-BK production. It was concluded that T2D individuals presented lower PKA, BK and NOx release as well as higher DesArg(9)-BK production and reduced PEH in relation to ND participants after a single exercise session.

Objective. The aim of this study was to verify the possibility of lactate minimum (LM) determination during a walking test and the validity of such LM protocol on predicting the maximal lactate steady-state (MLSS) intensity. Design. Eleven healthy subjects (24.2±4.5 yr; 74.3±7.7 kg; 176.9±4.1 cm) performed LM tests on a treadmill, consisting of walking at 5.5 km⋅h−1 and with 20–22% of inclination until voluntary exhaustion to induce metabolic acidosis. After 7 minutes of recovery the participants performed an incremental test starting at 7% incline with increments of 2% at each 3 minutes until exhaustion. A polynomial modeling approach (LMp) and a visual inspection (LMv) were used to identify the LM as the exercise intensity associated to the lowest [bLac] during the test. Participants also underwent to 2–4 constant intensity tests of 30 minutes to determine the MLSS intensity. Results. There were no differences among LMv (12.6±1.7%), LMp (13.1±1.5%), and MLSS (13.6±2.1%) and the Bland and Altman plots evidenced acceptable agreement between them. Conclusion. It was possible to identify the LM during walking tests with intensity imposed by treadmill inclination, and it seemed to be valid on identifying the exercise intensity associated to the MLSS.

Resumo Verificar as respostas de 24 horas da pressão arterial (PA) em jovens adultos após diferentes ordens de execução do exercício aeróbio (EA) e resistido (ER). Participarão do estudo dez homens saudáveis (22,6 ± 70,3; 3.7 anos ± 5,8 kg; 175,9 ± 5,8 centímetros). O estudo consistiu em quatro sessões experimentais realizadas de forma aleatórias: EA + ER (AR); ER + EA (RA); Circuito Concorrente (CC) e controle (CO). Todas as sessões tiveram a mesma duração e intensidade, EA: 15 min a 90% do limar de lactato mínimo indireto; ER: 15min a 90% de 12 RM com 12 repetições (seis exercícios). A PA foi medida antes, durante e 1 h (Microlife® BP3A1C) após a realização de exercícios em laboratório e 23 h durante as atividades diárias, utilizando a medição da pressão arterial ambulatorial (Dyna-MAPA®). A pressão arterial sistólica (PAS) no período de 24 horas e de vigília, e a diastólica (PAD), no período de 24 horas, o sono e de vigília, e a média da PA no período de vigília foram menores na sessão RA em comparação com a sessão CO apresentando um tamanho do efeito de moderado a alto (d de Cohen = -0,46 / -0,78). A área sob a curva da PAD na sessão AR foi menor do que na sessão CO no período de vigília (1004 ± 82 vs. 1065 ± 107; p < 0,047) e 24 h (1456 ± 103 vs 1528 ± 132; p < 0,026) períodos. A sessão RA apresentou maiores pontos de redução da PA durante 24 horas em relação ao outros protocolos.

Abstract This study investigated the efficacy of using a diary to record daily routines, combined with guidance on healthy lifestyle (GHL) by a physical educator, on promoting changes in health parameters in children. Sixty-three children (10 ± 0.8 years) were allocated to one of the three following groups: a control group (CON, n = 18); a group that did not use the diary, but received GHL (G, n = 23); or a group that both used the diary and received GHL (DG, n = 22). Blood pressure, body composition, physical fitness tests (PF), physical activity levels (PAL), and dietary intake profiles were assessed in children and their parents before and after 2 months of intervention. The DG group improved their performance in PF, increased PAL, and reduced body fat (p < 0.05). Additionally, 56% of families from both DG and G reduced their consumption of unhealthy foods and 70,6% increased their consumption of healthy foods. Overall, it was concluded that 2 months of using a diary to record daily routines combined with GHL by a physical educator improved PAL, PF, body composition, and dietary intake profiles of children and their families.