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Search Results: 1 - 10 of 112990 matches for " Marcos David Silva-Cavalcante "
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Estimativa das contribui es dos sistemas anaeróbio lático e alático durante exercícios de cargas constantes em intensidades abaixo do VO2max Estimation of contributions of the anaerobic lactic and alactic systems during constant-load exercises at intensities below the VO2max
Marcos David Silva-Cavalcante,Renata Gon?alves Silva,Rodrigo Poles Urso,Rogério Carvalho Silva
Revista Brasileira de Educa??o Física e Esporte , 2013,
Abstract: O objetivo do estudo foi estimar as contribui es do metabolismo anaeróbio lático (MAL) e alático (MAA) em intensidades abaixo do consumo máximo de oxigênio (VO2max). Dez homens (23 ± 4 anos, 176,4 ± 6,8 cm, 72,4 ± 8,2 kg, 12,0 ± 4,5 % de gordura corporal) realizaram um teste progressivo até a exaust o voluntária para identifica o do VO2max, da potência correspondente ao VO2max (WVO2max) e do segundo limiar ventilatório (LV2). Na segunda e na terceira visita foram realizados seis testes de cargas constantes (três testes por sess o) com intensidades abaixo do VO2max. Houve uma predominancia do MAL sobre o MAA durante os exercícios submáximos a partir da intensidade correspondente ao LV2, sendo significativamente maior em 90% VO2max (p < 0,05). Dessa forma, esses resultados podem auxiliar treinadores a aplicarem cargas de treinamento adequadas aos seus atletas, de acordo com a exigência metabólica da competi o. The purpose this study was that estimated contributions of the anaerobic lactic (MAL) and alactic (MAA) metabolism during constant load exercises at intensities below the maximal oxygen capacity uptake (VO2max). Ten males (23 ± 4 years, 176.4 ± 6.8 cm, 72.4 ± 8.2 kg, 12.0 ± 4.5 % of fat body) performed in the first visit a progressive test until exhaustion to identification of VO2max, power output corresponding to the VO2max (WVO2max) and second ventilatory threshold (LV2). On the second and third visit, the participants performed six constant workload tests (3 per session) with intensities below VO2max. There was a predominance of MAL about MAA during the exercises sub-maximal from intensity corresponding to the LV2, being significantly higher at 90% VO2max (p < 0.05). Thus, these results may help coaches to implement training loads appropriate to their athletes, according to the metabolic demand of the competition.
Thomaz Roberto Carvalho Carnaúba,Marcos David da Silva-Cavalcante,Jo?o Paulo Lopes da Silva,Ana Gabriela de M. Sim?es
Brazilian Journal of Biomotricity , 2011,
Abstract: CARNAúBA, T. R. C.; SILVA-CAVALCANTE, M. D.; SILVA, J. P. L.; SIM ES, A. G. M.; 1, ROZARIO, A. P. C.; BERTUZZI, R. C. M.; PIRES, F. O.; DE-OLIVEIRA, F. R.; LIMA-SILVA, A. E. Effects of music on perceptual responses and pacing strategy. Brazilian Journal of Biomotricity. v. 5, n. 3, p. 210-220, 2011. The purpose of this study was verify the effects of music on perceptual responses and pacing strategy during 5-km running. Fifteen men (22.5 ± 3.5 years; 177.7 ± 6 cm; 76.0 ± 7.0 kg) they accomplished three tests in a mat. The first two tests were accomplished without music to identify the best time of the subjects in a situation it controls. The third test was accomplished with music during all races. During the tests the rating of perceived exertion (RPE), the heart rate (HR) and the percentage of dissociative thoughts (PD) were monitored to each 1000m and the velocity to each 500m. The music increased significantly the velocity during the 500, 1000, 1500 and 2500m and the PD during the 1000 and 2000m than for the control condition (p<0.05). There was no significant difference in the RPE between the conditions (P>0.05). The results suggest that music enhances the focus on signs that are not related to fatigue and blockade the RPE, resulting in increase velocity and performance during the 5-Km running.
Caffeine Increases Anaerobic Work and Restores Cycling Performance following a Protocol Designed to Lower Endogenous Carbohydrate Availability
Marcos David Silva-Cavalcante, Carlos Rafaell Correia-Oliveira, Ralmony Alcantara Santos, Jo?o Paulo Lopes-Silva, Hessel Marani Lima, Romulo Bertuzzi, Marcos Duarte, David John Bishop, Adriano Eduardo Lima-Silva
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0072025
Abstract: The purpose this study was to examine the effects of caffeine ingestion on performance and energy expenditure (anaerobic and aerobic contribution) during a 4-km cycling time trial (TT) performed after a carbohydrate (CHO) availability-lowering exercise protocol. After preliminary and familiarization trials, seven amateur cyclists performed three 4-km cycling TT in a double-blind, randomized and crossover design. The trials were performed either after no previous exercise (CON), or after a CHO availability-lowering exercise protocol (DEP) performed in the previous evening, followed by either placebo (DEP-PLA) or 5 mg.kg?1 of caffeine intake (DEP-CAF) 1 hour before the trial. Performance was reduced (?2.1%) in DEP-PLA vs CON (421.0±12.3 vs 412.4±9.7 s). However, performance was restored in DEP-CAF (404.6±17.1 s) compared with DEP-PLA, while no differences were found between DEP-CAF and CON. The anaerobic contribution was increased in DEP-CAF compared with both DEP-PLA and CON (67.4±14.91, 47. 3±14.6 and 55.3±14.0 W, respectively), and this was more pronounced in the first 3 km of the trial. Similarly, total anaerobic work was higher in DEP-CAF than in the other conditions. The integrated electromyographic activity, plasma lactate concentration, oxygen uptake, aerobic contribution and total aerobic work were not different between the conditions. The reduction in performance associated with low CHO availability is reversed with caffeine ingestion due to a higher anaerobic contribution, suggesting that caffeine could access an anaerobic “reserve” that is not used under normal conditions.
Caffeine Alters Anaerobic Distribution and Pacing during a 4000-m Cycling Time Trial
Ralmony de Alcantara Santos, Maria Augusta Peduti Dal Molin Kiss, Marcos David Silva-Cavalcante, Carlos Rafaell Correia-Oliveira, Romulo Bertuzzi, David John Bishop, Adriano Eduardo Lima-Silva
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0075399
Abstract: The purpose of the present study was to investigate the effects of caffeine ingestion on pacing strategy and energy expenditure during a 4000-m cycling time-trial (TT). Eight recreationally-trained male cyclists volunteered and performed a maximal incremental test and a familiarization test on their first and second visits, respectively. On the third and fourth visits, the participants performed a 4000-m cycling TT after ingesting capsules containing either caffeine (5 mg.kg?1 of body weight, CAF) or cellulose (PLA). The tests were applied in a double-blind, randomized, repeated-measures, cross-over design. When compared to PLA, CAF ingestion increased mean power output [219.1±18.6 vs. 232.8±21.4 W; effect size (ES) = 0.60 (95% CI = 0.05 to 1.16), p = 0.034] and reduced the total time [419±13 vs. 409±12 s; ES = ?0.71 (95% CI = ?0.09 to ?1.13), p = 0.026]. Furthermore, anaerobic contribution during the 2200-, 2400-, and 2600-m intervals was significantly greater in CAF than in PLA (p<0.05). However, the mean anaerobic [64.9±20.1 vs. 57.3±17.5 W] and aerobic [167.9±4.3 vs. 161.8±11.2 W] contributions were similar between conditions (p>0.05). Similarly, there were no significant differences between CAF and PLA for anaerobic work (26363±7361 vs. 23888±6795 J), aerobic work (68709±2118 vs. 67739±3912 J), or total work (95245±8593 vs. 91789±7709 J), respectively. There was no difference for integrated electromyography, blood lactate concentration, heart rate, and ratings of perceived exertion between the conditions. These results suggest that caffeine increases the anaerobic contribution in the middle of the time trial, resulting in enhanced overall performance.
Environmentally associated ticks (Acari: Ixodidae) in Campo Grande, Mato Grosso do Sul, Brazil Carrapatos (Acari: Ixodidae) associados com o ambiente em Campo Grande, Mato Grosso do Sul, Brasil
Marcos Valério Garcia,Dayana Campelo da Silva,Robson Ferreira Cavalcante de Almeida,Rodrigo Casquero Cunha
Revista Brasileira de Parasitologia Veterinária , 2013,
Abstract: Herein, we report tick species found on wild and domestic animals and in the environment during a one-year sampling period at the Brazilian Farming Research Company beef cattle unit (Embrapa Beef Cattle), which is located within the urban area of Campo Grande, Mato Grosso do Sul, Brazil. From 55 wild hosts including six different species (Nasua nasua, Cebus spp., Cerdocyon thous, Myrmecophaga tridactyla, Tamandua tetradactyla and Dasyprocta aguti), 323 ticks were collected. Amblyomma ovale ticks were found solely on coatis, and Amblyomma nodosum was identified solely on anteaters. No ticks were found on capuchin monkeys. However, Amblyomma cajennense was found on all parasitized host species with the exception of capuchin monkeys. Giant anteaters displayed the highest infestation abundance, with a mean of 53 ticks∕animal. Environmental sampling yielded 166 adult A. cajennense ticks. The tick species found on domestic animals (Rhipicephalus (Boophilus) microplus, R. sanguineus, Dermacentor nitens and A. cajennense) were those typically found on these hosts in Brazil. The most prevalent tick species, A. cajennense, was found on both wild and domestic animals and was also prevalent in the environment. Thus, this tick species is the primary vector that allows pathogens to bridge wild and domestic animals in the Cerrado. Neste trabalho s o descritas as espécies de carrapatos de animais selvagens e domésticos e do ambiente coletados por um ano na EMBRAPA Gado de Corte localizado na área urbana de Campo Grande, Mato Grosso do Sul, Brasil. Dos 55 hospedeiros selvagens de seis espécies diferentes (Nasua nasua, Cebus spp., Cerdocyon thous, Myrmecophaga tridactyla, Tamandua tetradactyla e Dasyprocta aguti) foram coletados 323 carrapatos. Amblyomma ovale foi encontrado apenas em quatis e Amblyomma nodosum apenas sobre tamanduás. Nenhum carrapato foi encontrado sobre macacos-prego. Por outro lado, Amblyomma cajennense foi encontrado em todos os hospedeiros com exce o dos macacos-pregos. A maior abundancia de infesta o foi aquela em tamanduás-bandeira com média de 53 carrapatos∕animal. No ambiente foram capturados 166 carrapatos, todos da espécie A. cajennense. As espécies de carrapatos em animais domésticos (Rhipicephalus (Boophilus) microplus, Rhipicephalus sanguineus, Dermacentor nitens e A. cajennense) foram aquelas características nestes hospedeiros no Brasil. De forma geral a espécie de carrapato A. cajennense foi a mais prevalente sendo encontrada em animais domésticos e selvagens bem como no ambiente. Portanto, esta é a principal espécie de vetor a estabele
Elementos do trabalho voluntário: motivos e expectativas na pastoral da crian a de Jo o Pessoa/PB [doi: 10.5329/RECADM.20111001007]
Carlos Eduardo Cavalcante,Washington José de Souza,Abdon Silva Ribeiro da Cunha,Marcos Adller de Almeida Nascimento
Revista Eletr?nica de Ciência Administrativa - RECADM , 2011, DOI: 10.5329/647
Abstract: RESUMO O trabalho voluntário tem crescido expressivamente e possui um papel importante na sociedade. Assim, é importante delinear as motiva es que levam voluntários a renunciarem ao benefício próprio, doando tempo e talentos em prol do outro. Este estudo tem por objetivo pesquisar os motivos e expectativas dos voluntários que atuam na Pastoral da Crian a. Foi realizada com voluntários ligados a vinte e cinco paróquias de Jo o Pessoa/PB distribuídas entre vários bairros desta cidade Por meio de 157 questionários. O instrumento de coleta de dados aplicado foi um questionário baseado em Souza, Medeiros e Fernandes (2006) e dividido em três se es. O tratamento dos dados foi feito a partir de medidas estatísticas (média e desvio-padr o) – na primeira se o – e utiliza o de percentagens – na segunda e terceira se es. Os perfis “afetivo” e “altruísta” predominam na realiza o do trabalho voluntário, caracterizando um voluntariado com interesse no resgate da cidadania e elevado grau de abnega o. Palavras-Chave Pastoral da Crian a; trabalho voluntário; perfil. ABSTRACT Volunteer work has grown significantly and has had an important role in society. It is therefore important to establish the motivations that lead volunteers to give up their own good for the welfare of other people. Thus, this study aims at investigating the reasons and expectations of volunteers who work for the Pastoral da Crian a. The survey was conducted among volunteers linked to twenty-five parishes in the city of Jo o Pessoa. The data collection instrument was a questionnaire, based on Souza, Medeiros and Fernandes (2006). A hundred and fifty seven questionnaires were collected. The data was analysed, in the first section, using statistical measures (mean and standard deviation), and, in the second and third sections, using percentage. The "affective" and "selfless" profiles predominate in volunteer work, which characterises volunteers who are interested in the local recovery of citizenship and who have a high degree of selflessness. Keywords Pastoral da crian a; volunteer work; profile.
Carlos Eduardo Cavalcante,Washington José de Souza,Abdon Silva Ribeiro da Cunha,Marcos Adller de Almeida Nascimento
Revista PRETEXTO , 2012,
Abstract: A análise da validade de um instrumento quantitativo que permita conhecer o que conduz, o que mantém e o que faz deixar um voluntário a sua atividade é o objetivo deste trabalho. Quanto aos objetivos, esta pesquisa é descritiva, uma vez que apresenta a análise da validade de um instrumento quantitativo que busca compreender e descrever motivos do trabalho voluntário na Pastoral da Crian a. O instrumento é baseado em idéias teóricas de Souza, Medeiros e Fernandes (2006). O índice de confiabilidade – Alfa de Cronbach – alcan ou valores entre 0,7 e 0,8. No que tange ao Teste de Adequa o da Amostra Kaiser- Meyer-Olkin também um bom índice foi obtido: 0,74. Apesar dos bons resultados de confiabilidade e dos testes de adequa o da Análise Fatorial, em nenhuma das variáveis foi encontrada a combina o esperada, qual seja: quest es versus perfil. Há a necessidade de melhorar o sentido semantico de determinados fatores, ou mesmo de aumentar a quantidade de indicadores, para que eles consigam gerar outras correla es entre eles.
Comportamento organizacional no trabalho voluntário: motivos, perfis e correla es na pastoral da crian a
Carlos Eduardo Cavalcante,Washington José de Souza,Abdon Silva Ribeiro da Cunha,Marcos Adller de Almeida Nascimento
Estudos do CEPE , 2010,
Abstract: Este estudo tem por objetivo conhecer elementos que motivam a entrada de pessoas no trabalho voluntário, especificamente na Pastoral da Crian a, nas cidades de Jo o Pessoa e Natal. A pesquisa foi realizada junto a voluntários de vinte e cincoparóquias da cidade de Jo o Pessoa/PB e vinte da cidade de Natal/RN, totalizando 324 questionários, em uma popula o estimada de 500 voluntários. O instrumento de coleta de dados aplicado foi um questionário de perguntas elaboradas a partir de idéias teóricas extraídas de Souza, Medeiros e Fernandes (2006). O tratamento dosdados foi feito a partir da aplica o de medidas estatísticas multivariadas que buscaram explicar a correla o (Pearson e Spearman) existente entre os motivos de “entrada” e os dados sócio-demograficos. No momento seguinte, aplicaram-se as técnicas “Análise F-ANOVA” e “teste de Bonferroni” entre as variáveis de estudo e asvariáveis sócio-econ micas “estado civil” e “ocupa o”, no intuito de comprovar se há diferen a nas médias das respostas dos voluntários. Os perfis “afetivo” e “altruísta” tiveram as maiores médias. Surgiram correla es entre os motivos de entrada, a idade e renda familiar e diferen as entre o grupo de aposentados e o de voluntários que n o tem renda própria. Abstract This study aims at understanding factors that motivate people to engage in volunteer work, specifically in the Pastoral da Crian a in the cities of Jo o Pessoa, Paraíba, and Natal, Rio Grande do Norte. he research was conducted with volunteers from twenty-five parishes in the city of Jo o Pessoa and twenty in Natal, which totalled 324 questionnaires in a population of 500 volunteers. The data collection instrumentwas a questionnaire drawn from theoretical ideas by Souza, Medeiros and Fernandes (2006). Data analysis was done by the application of multivariate statistical techniques that sought to explain the correlation (Pearson and Spearman) between the reasons for engagement and socio-demographic data. Then, the techniques "ANOVA-F Analysis" and "Bonferroni" were applied among the study variables and the socio-economic variables "marital status" and "occupation" in orderto test if there is difference in the volunteers average responses. The "affective" and "selfless" profiles had the highest average. In contrast, profiles that tend to selfishness had lower averages. Correlations emerged among the reasons for engagement, age and family income and differences between the group of retired volunteers and those who do not have their own income.
Estimativa da gordura corporal através de equipamentos de bioimpedancia, dobras cutaneas e pesagem hidrostática
Rodrigues, Maurício Nunes;Silva, Sidney Cavalcante da;Monteiro, Walace David;Farinatti, Paulo de Tarso Veras;
Revista Brasileira de Medicina do Esporte , 2001, DOI: 10.1590/S1517-86922001000400003
Abstract: the main advantage of the bioelectric impedance method (bia) in the determination of body fat (%bf) is the simplicity of the procedure. however, its accuracy and reliability have been criticized. the purpose of this study was to compare the %bf obtained by bia (rjl-101; biodynamics a-310, maltron bf-900 e bf-906), by skinfold thickness (st), and by underwater weighing (uw). twenty-five subjects, divided in homogenous groups according to age (18 to 36 years), sex (men), and race (white) participated in the study. bia measures were taken using the lukaski et al. standardization (1985,1986). st was taken by using the equation of 3 and 7 skinfolds (jackson, pollock, 1978). the values of %bf and residual volume for the uw were estimated by the siri (1961) and goldman and becklake (1959) equations. statistical analysis was calculated by: a) repeated measures anova followed by the tukey post-hoc test; b) pearson (r) correlation; c) standard error of estimate (see) of the bia and st compared to uw. the results indicated that: a) there were no significant differences for %bf measures obtained by the bia devices; b) the %bf obtained by the a-310 and bf-906 devices did not match with the uw measures (p < 0.01); c) see was high for all devices, except for the rjl-101; d) the correlation coefficients were low to moderate for all devices, the bf-906 showing the higher values; e) the st showed greater values of r and fewer see than the bia. in conclusion, the findings do not allow to state that a bia device is better than the others to assess %bf, but the st seems to be more powerful and reliable than the bia for %bf estimation. notwithstanding, the results should be confirmed by more sophisticated experimental designs, with a closer control of sampling bias for type i and ii errors.
Respostas da freqüência cardíaca de pico em testes máximos de campo e laboratório
Santos, Alexandre Lima dos;Silva, Sidney Cavalcante;Farinatti, Paulo de Tarso Veras;Monteiro, Walace David;
Revista Brasileira de Medicina do Esporte , 2005, DOI: 10.1590/S1517-86922005000300005
Abstract: background and objective: the peak heart rate (hrpeak) assessed in maximum laboratory tests has been used to determine the aerobic exercise intensity in field situations. however, hrpeak values may differ in field and laboratory situations, which can influence the relative intensity of the prescribed workloads. the objective of this study was to measure the hrpeak responses in laboratory and field maximum tests, analyzing their influence in the exercise prescription. methods: twenty-five physically active men aged 21-51 yrs (28.9 ± 8 yrs) executed a 2,400 m field test in a running track and an individualized maximum treadmill ramp protocol. all tests were performed within two weeks, in a counterbalanced order. before each test, the temperature and air humidity were checked, and the subjects were told no to engage in any physical activity 48 hours before. differences between hrpeak and environmental conditions (temperature and humidity) in field and laboratory situations were respectively tested by paired and simple student's t tests (p < 0.05). results: hrpeak values were significant higher in the field test than in the laboratory protocol, reaching 10 beats per minute in some cases. these differences may be partially accounted for a significant higher temperature and air humidity in the field conditions. conclusion: in conclusion, maximum field tests seem to elicit higher hrpeak values than laboratory protocols, suggesting that the former procedures are more likely precise to determine the relative intensity of aerobic effort in physical training.
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