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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Efeito da ingestão isolada de cafeí­na e bicarbonato de sódio sobre a contribuição energética, desempenho e reativação parassimpática em simulação de luta de taekwondo / Effect of the isolated intake of caffeine and sodium bicarbonate on the energy contribution, performance and parasympathetic reactivation after simulation of taekwondo fight

João Paulo Lopes da Silva 11 December 2017 (has links)
O objetivo do trabalho foi investigar o efeito da suplementação isolada de cafeína e bicarbonato de sódio sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática após simulação de luta de taekwondo. Para tanto, a presente tese foi dividida em estudo 1, com a suplementação de cafeína e estudo 2, com a suplementação de bicarbonato de sódio. Portanto, no estudo 1, o objetivo foi investigar o efeito da suplementação de cafeína sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática em simulação de luta de taekwondo. 10 atletas de taekwondo foram submetidos a duas sessões experimentais separadas por no mínimo de 48 horas entre elas. Nas duas visitas os atletas consumiram uma cápsula contendo cafeína (5 mg.kg-1 de massa corporal) ou placebo (celulose) uma hora antes da simulação da luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minuto de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço (PSE) antes e após cada round,e a frequência cardíaca (FC) e a contribuição dos sistemas energéticos foi estimada durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparados usando análise de variância de dois fatores (condição e tempo). Adicionalmente, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições cafeína e placebo. Os principais resultados indicam que: a suplementação de cafeína aumentou a contribuição do sistema glicolítico em relação ao placebo. Porém, a cafeína não melhorou o desempenho ou alterou a PSE, a FC ou a contribuição dos sistemas oxidativo e ATP-CP quando comparados ao placebo. Adicionalmente, nenhum índice da reativação parassimpática foi afetado pela suplementação de cafeína. No estudo 2, o objetivo do estudo foi investigar o efeito da suplementação de bicarbonato de sódio sobre a contribuição dos sistemas energéticos durante a simulação de luta de taekwondo. Para tanto, foram avaliados 9 atletas de taekwondo, os quais foram submetidos a duas condições experimentais, separadas por um mínimo de 48 horas entre elas. Nas duas visitas os atletas ingeriram uma cápsula contendo 0,03 g.kg-1 da massa corporal de NaHCO3- ou placebo (carbonato de cálcio), 90 minutos antes da simulação de luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minutos de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço antes e após cada round, a frequência cardíaca e a contribuição dos sistemas energéticos foram estimadas durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparadas usando análise de variância de dois fatores (condição e tempo). Além disso, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições NaHCO3 e placebo. Os principais resultados demonstraram que a suplementação de NaHCO3 aumentou a contribuição do sistema glicolítico e o tempo total de ataque em relação ao placebo. Porém, o NaHCO3 não alterou a FC, a PSE ou a contribuição dos sistemas oxidativo e ATP-CP durante a simulação de luta quando comparados ao placebo. Além disso, nenhum índice da reativação parassimpática foi afetado pela suplementação de NaHCO3 ou placebo / The aim of this study was to investigate the isolated effect of caffeine and sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a simulated taekwondo combat. Therefore, this thesis was divided in two studies: study 1 investigated the effect of caffeine, while study 2 investigated the effect of sodium bicarbonate. Thus, in study 1, the aim was to investigate the effect of caffeine supplementation on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a taekwondo combat. Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either 5 mg?kg-1 body mass of caffeine or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spend fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate and the estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated. Lactate concentration, rate of perceived of exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test in both caffeine and placebo conditions. The main results showed that caffeine ingestion increased the estimated glycolytic system when compared to placebo condition. However, caffeine ingestion did not alter the rate of perceived exertion, heart rate, estimated oxidative and ATP-PCr contribution or improve the performance in relation to placebo condition. Furthermore, caffeine ingestion did not influence post-exercise parasympathetic reactivation following a taekwondo simulation when compared to placebo condition. In study 2, the main aim of the study was to investigate the effect of sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during simulated taekwondo combat. Nine taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed 300 mg?kg-1 body mass of sodium bicarbonate or calcium bicarbonate (placebo) 90 minutes before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spent fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate, estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was calculated. Lactate concentration, rate of perceived exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test. The main results showed that sodium bicarbonate ingestion increased the lactate concentration, estimated glycolytic contribution and total attack time when compared with placebo condition. However, sodium bicarbonate ingestion did not influence heart rate, rate of perceived exertion, estimated oxidative and ATP-PCr contribution during combat simulation compared to placebo. Furthermore, no indices of parasympathetic reactivation were different between sodium bicarbonate and placebo conditions
182

Respostas fisiológicas e análise técnico-tática em atletas de brasilian jiu-jitsu submetidos à luta fragmentada e simulação de competição / Physiological responses and technical-tactical analysis in of Brazilian jiu-jitsu athletes during fragmented fight and during simulated competition

Leonardo Vidal Andreato 28 February 2014 (has links)
O objetivo deste estudo foi analisar as respostas fisiológicas e realizar análise técnico-tática em atletas de Brazilian jiu-jitsu durante luta fragmenta e simulação de competição. Para isso, 10 atletas foram submetidos a avaliações em luta fragmentada (2 min, 5 min, 8 min e 10 min) e 10 atletas a avaliações em competição simulada (4 combates de 10 min). Foram realizadas coletas sanguíneas (para inferência da demanda energética, respostas hormonais, lesões celulares e equilíbrio hidroeletrolítico), aplicados testes físicos e escalas de percepções de esforço e recuperação. Adicionalmente, os combates foram filmados para análise técnico-tática e determinação da estrutura temporal. Os principais resultados apontam que: (1) nas lutas fragmentas, os combates de maior duração geraram concentrações mais elevadas de lactato e glicose, assim como maior percepção subjetiva de esforço e diminuição da resistência de pegada em teste específico. No entanto, não houve alteração importante da estrutura temporal em nenhum tempo de luta; (2) na competição simulada, os últimos combates apresentaram menores concentrações de lactato, catecolaminas e insulina. Adicionalmente, ocorreram aumentos dos marcadores de lesões celulares nos últimos combates indicando possível dano muscular. A força máxima isométrica de preensão manual apresentou declínio, predominantemente, a partir do terceiro combate. Embora esses dados apontem para a instalação de fadiga, a estrutura temporal dos combates não foi alterada significativamente. As percepções de esforço e recuperação não se alteraram durante a competição simulada. Assim, conclui-se que tempos diferentes de combate resultam em respostas metabólicas diferentes, as quais não produzem alterações importantes de desempenho. No entanto, os combates sucessivos de uma competição geram diminuição gradual da atividade adrenérgica e glicolítica, as quais são acompanhadas de aumento gradual de indicadores de dano celular e diminuição gradual da força de preensão manual / The aim of this study was to analyze physiological responses and perform technicaltactical analysis in Brazilian Jiu-Jitsu athletes during fragmented fight and simulated competition. For that, 10 athletes were submitted to assessment in fragmented fight (2 min, 5 min, 8 min and 10 min) and 10 athletes in simulated competition (4 combats of 10 min). Blood samples were taken (to assess the energy demand, hormonal responses , cell damage and hidroelectrolyte balance) and physical tests and scales of perceptions of effort and recovery were applied. Additionally, the fights were recorded for technical-tactical analysis and to determine the time structure. The main results show that: (1) in the fragmented fight, the longer combats generated higher lactate and glucose concentrations, as well as greater rate of perceived exertion and decreased hand grip endurance in specific test. However, there was no significant change in the time structure in any time of fight, (2) in simulated competitions, the last fights had lower lactate, catecholamines and insulin concentrations. Additionally, increases in markers of cellular damage occurred in the last fights indicating possible muscle damage. The maximal isometric handgrip strength showed decrease predominantly from the third fight. Although these results point to the onset of fatigue, the time structure of the fights was not significantly altered. Effort and recovery perceptions did not change during the simulated competition. Thus, it is concluded that different times of combat result in different metabolic responses which do not produce significant changes in performance. However, successive combats from competition generate gradual decrease of adrenergic and glycolytic activity, which are accompanied by gradual increase of indicators of cellular damage and gradual decrease in handgrip strength
183

Home advantage no judô: estudo sobre o sistema de ranqueamento mundial / Home advantage in judo: study on the world ranking system

Ursula Ferreira Julio 25 July 2011 (has links)
Em 2009, a Federação Internacional de Judô (FIJ) instituiu um sistema de ranqueamento (SR) para classificar os atletas em suas categorias de disputa e para os Jogos Olímpicos de Londres 2012. Porém, o SR não considera o fenômeno conhecido como home advantage, relacionado à vantagem de vencer quando se compete em casa. Esse fenômeno ainda não foi estudado no judô e se comprovado traz implicações para o SR. Assim, o objetivo deste estudo foi verificar se há ocorrência de home advantage nas competições que integram o SR no judô, para a conquista de medalha e número de lutas vencidas. Para tal, foram analisadas todas as competições internacionais de judô do SR realizadas em 2009. Para verificar se os atletas que competiram em casa tiveram mais chance de conquistar medalha foi utilizada a análise de regressão logística e para verificar se houve associação do número de lutas vencidas e competir em casa foi utilizado o modelo linear generalizado de Poisson. Os modelos contaram com uma variável de ajuste referente à qualidade relativa dos atletas em duas possibilidades: posição no SR da FIJ e neutro (construído com lutas disputadas em território neutro). A amostra foi dividida em: Grupo I - todas as participações; Grupo II - somente os atletas que haviam competido dentro e fora de casa. Dado que alguns atletas não puderam lutar em território neutro e, portanto, não tiveram codificação para esse SR, foram criados duas subamostras do Grupo I e do Grupo II, excluindo os atletas sem codificação nesta variável. Todas as análises foram realizadas considerando os gêneros conjunta e separadamente. A variável qualidade relativa foi significante em todas as análises e também modificou os modelos (p<0,001). Ao considerarmos a subamostra do Grupo II, a razão de chance para conquista de medalhas foi superior para os atletas que competiram em casa para o grupo masculino (2,33; p<0,001) e feminino (1,58; p = 0,019). A associação entre número de lutas vencidas e competir em casa foi significante para os atletas do masculino (p<0,001), mas não significante para o feminino (p = 0,088). A ausência da vantagem no feminino para número de lutas vencidas pode ter sido limitada e confundida com o número reduzido de atletas participantes em muitas das competições. As atletas que conquistaram medalha em competições mais vazias, não precisaram vencer mais lutas, dado que um número reduzido de vitórias garantia a medalha. É possível que a torcida seja a principal responsável pelos achados, tanto por influenciar o julgamento dos árbitros a favorecer os atletas da casa como pela motivação para os atletas. Outra possibilidade é que aspectos associados à dominância territorial tenham influenciado as disputas masculinas, porém não as femininas. Assim, foi comprovada a existência do home advantage nas competições que integram o SR de judô para conquista de medalha no masculino e feminino, e para número de lutas vencidas apenas para o masculino. Desta forma, é provável que os atletas de países que sediam competições do SR tenham vantagem para a obtenção da classificação olímpica / In 2009 the International Judo Federation (IJF) established a ranking system (RS) to classify athletes in the competition categories and in the distribution of vacancies for the London 2012 Olympic Games. Nevertheless, the RS does not consider the phenomenon known as home advantage, i.e. the advantage of winning when competing in your home country. This phenomenon has not been studied in judo and its implications for the RS have not been proven. The objective of this study was to determine whether there was occurrence of home advantage in competitions that use the RS in judo, in winning a medal, and in the number of matches won. Therefore, we analyzed all international judo competitions using the RS in 2009. Logistic regression analysis was used to verify if the athletes who competed in their home countries were more likely to win a medal, and we used the Poisson generalized linear model to check whether there were associations between the number of matches won and competing at home. The models have an adjustment variable in the relative quality of athletes in two possibilities: position in the IJF RS and matches played on neutral territory. The sample was divided into two groups: Group I all participants and Group II only athletes who had competed inside and outside their home country. Given that some athletes could not fight on neutral territory and therefore did not have this RS coding, a sub-sample of Group I and a sub-sample of Group II were created, excluding athletes without the coding from this variable. All tests were performed considering the groups together and separately. The relative quality variable was significant in all tests and also modified the models (p <0.001). For the sub-sample of Group II the odds ratio for winning medals was higher for the athletes who competed at home for the male group (2.33, p <0.001) and the female group (1.58, p = 0.019). The association between the number of matches won and competing at home was significant for the male athletes (p <0.001), but not for the females (p = 0.088). The absence of the female advantage in the number of matches won may have been limited and confused by the small number of athletes participating in many of the competitions. The athletes who won medals in competitions with fewer competitors did not need to win more matches since a small number of wins guaranteed the medal. It is possible that the crowd was mainly responsible for the findings, both in influencing the judgement of the referees to favour the home athletes and in motivating the athletes. Another possibility is that aspects related to territorial dominance influenced the male competitors but not the female competitors. Thus, the existence of home advantage was observed in the competitions that used the judo RS in the achievement of medals for males and females, and in the number of matches won, only for males. Thus, it is likely that athletes from countries that host competitions using the RS have an advantage for obtaining the Olympic classification
184

La guerre par les drones : un système immunitaire ? : une étude du rapport entre corps, politique et nouvelles formes de conflit / Genealogy of disexposure : a philosophical approach on drone warfare

Portron, Margaux 30 March 2017 (has links)
Ce travail se fonde sur la littérature critique existante sur les drones militaires, des études de cas et le travail de Michel Foucault sur le biopouvoir pour mettre en évidence les ressorts du pouvoir immunitaire. Nous cherchons à définir la logique immunitaire et à montrer ses ramifications en utilisant une de ses incarnations : les avions sans pilote utilisés à des fins militaires pour la surveillance et le bombardement par les États-Unis notamment. Ce travail analyse principalement les relations de pouvoir auxquelles sont soumis les corps dans l’assemblage. Si les travaux actuels ont insisté sur la place du corps du pilote de drone, ou opérateur, dans l’assemblage disciplinaire, notre étude des corps au sol comme partie intégrante du dispositif homme-machine met en évidence une logique constitutive du nous et du eux. La souveraineté est en effet le mécanisme qui fonde un groupe sur le commun, en excluant les autres, et qui trace ses frontières sur le principe de préservation de ce groupe. Ces frontières peuvent être celles d’un État, du monde occidental, mais aussi de certains quartiers, dans les villes, plus rentables que d’autres. Ce souci de préservation d’une communauté va aller de pair avec le développement d’un racisme institutionnalisé servant à organiser les vies à protéger et celles qu’on peut abandonner et même, et c’est pour cela que le pouvoir immunitaire superpose biopouvoir et pouvoir souverain, à éliminer si l’on estime qu’elles posent une menace. / This work draws on the existing critical literature on drone warfare, case studies and Michel Foucault’s work on biopower to highlight how immunity unfolds. I seek to define immunity by using one of its embodiments: pilotless devices used in contemporary conflicts for surveillance and bombing, mostly by the United States. This work mainly analyses the power relations to which the bodies that form the drone assemblage are subjected. If current analyses have insisted on the position of the drone pilot, or drone operator, in the disciplinary assemblage, my focus on the bodies on the ground as an essential part of the man-machine apparatus shows a way of constituting us and them. Sovereignty is indeed the mechanism by which a group constitutes itself on what they have in common, excluding others, and which confuses its borders with the principle of preservation. These borders can be those of a State, of the western world, but also of some city neighbourhoods. This obsession with community preservation is going to develop in parallel with institutionalised racism, which serves to organise lives which must be protected and those which can be abandoned and even killed if considered a threat. This is why I argue that biopower and sovereign power overlap in immune power.
185

Efeito da ingestão isolada de cafeí­na e bicarbonato de sódio sobre a contribuição energética, desempenho e reativação parassimpática em simulação de luta de taekwondo / Effect of the isolated intake of caffeine and sodium bicarbonate on the energy contribution, performance and parasympathetic reactivation after simulation of taekwondo fight

Silva, João Paulo Lopes da 11 December 2017 (has links)
O objetivo do trabalho foi investigar o efeito da suplementação isolada de cafeína e bicarbonato de sódio sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática após simulação de luta de taekwondo. Para tanto, a presente tese foi dividida em estudo 1, com a suplementação de cafeína e estudo 2, com a suplementação de bicarbonato de sódio. Portanto, no estudo 1, o objetivo foi investigar o efeito da suplementação de cafeína sobre a contribuição dos sistemas energéticos, desempenho e reativação parassimpática em simulação de luta de taekwondo. 10 atletas de taekwondo foram submetidos a duas sessões experimentais separadas por no mínimo de 48 horas entre elas. Nas duas visitas os atletas consumiram uma cápsula contendo cafeína (5 mg.kg-1 de massa corporal) ou placebo (celulose) uma hora antes da simulação da luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minuto de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço (PSE) antes e após cada round,e a frequência cardíaca (FC) e a contribuição dos sistemas energéticos foi estimada durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparados usando análise de variância de dois fatores (condição e tempo). Adicionalmente, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições cafeína e placebo. Os principais resultados indicam que: a suplementação de cafeína aumentou a contribuição do sistema glicolítico em relação ao placebo. Porém, a cafeína não melhorou o desempenho ou alterou a PSE, a FC ou a contribuição dos sistemas oxidativo e ATP-CP quando comparados ao placebo. Adicionalmente, nenhum índice da reativação parassimpática foi afetado pela suplementação de cafeína. No estudo 2, o objetivo do estudo foi investigar o efeito da suplementação de bicarbonato de sódio sobre a contribuição dos sistemas energéticos durante a simulação de luta de taekwondo. Para tanto, foram avaliados 9 atletas de taekwondo, os quais foram submetidos a duas condições experimentais, separadas por um mínimo de 48 horas entre elas. Nas duas visitas os atletas ingeriram uma cápsula contendo 0,03 g.kg-1 da massa corporal de NaHCO3- ou placebo (carbonato de cálcio), 90 minutos antes da simulação de luta de taekwondo, composta por 3 rounds de 2 minutos com 1 minutos de intervalo entre os rounds. A ordem das sessões experimentais foi randomizada, duplo-cego e cruzada. Todas as simulações de luta foram filmadas para quantificar as ações técnico-táticas durante os rounds. Foram mensuradas a concentração de lactato, a percepção subjetiva de esforço antes e após cada round, a frequência cardíaca e a contribuição dos sistemas energéticos foram estimadas durante a simulação de luta. Além disso, foram mensurados alguns índices da reativação parassimpática após o terceiro round. A concentração de lactato, a PSE, a FC e a contribuição dos sistemas energéticos foram comparadas usando análise de variância de dois fatores (condição e tempo). Além disso, os índices da reativação parassimpática foram comparados utilizando o teste t de Student entre as condições NaHCO3 e placebo. Os principais resultados demonstraram que a suplementação de NaHCO3 aumentou a contribuição do sistema glicolítico e o tempo total de ataque em relação ao placebo. Porém, o NaHCO3 não alterou a FC, a PSE ou a contribuição dos sistemas oxidativo e ATP-CP durante a simulação de luta quando comparados ao placebo. Além disso, nenhum índice da reativação parassimpática foi afetado pela suplementação de NaHCO3 ou placebo / The aim of this study was to investigate the isolated effect of caffeine and sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a simulated taekwondo combat. Therefore, this thesis was divided in two studies: study 1 investigated the effect of caffeine, while study 2 investigated the effect of sodium bicarbonate. Thus, in study 1, the aim was to investigate the effect of caffeine supplementation on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during a taekwondo combat. Ten taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed a capsule containing either 5 mg?kg-1 body mass of caffeine or placebo (cellulose) one hour before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spend fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate and the estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was evaluated. Lactate concentration, rate of perceived of exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test in both caffeine and placebo conditions. The main results showed that caffeine ingestion increased the estimated glycolytic system when compared to placebo condition. However, caffeine ingestion did not alter the rate of perceived exertion, heart rate, estimated oxidative and ATP-PCr contribution or improve the performance in relation to placebo condition. Furthermore, caffeine ingestion did not influence post-exercise parasympathetic reactivation following a taekwondo simulation when compared to placebo condition. In study 2, the main aim of the study was to investigate the effect of sodium bicarbonate ingestion on performance, estimated energy system contribution and on post-exercise parasympathetic reactivation during simulated taekwondo combat. Nine taekwondo athletes completed two experimental sessions separated by at least 48 hours. Athletes consumed 300 mg?kg-1 body mass of sodium bicarbonate or calcium bicarbonate (placebo) 90 minutes before the combat simulation (3 rounds of 2 min separated by 1-min passive recovery), in a double blinded, randomized, repeated-measures crossover design. All simulated combat was video recorded to quantify the time spent fighting in each round. Lactate concentration and rate of perceived exertion were measured before and after each round, while heart rate, estimated contribution of oxidative, ATP-PCr and glycolytic systems were calculated during the combat simulation. Furthermore, parasympathetic reactivation after the combat simulation was calculated. Lactate concentration, rate of perceived exertion, heart rate, estimated system contributions and indices of time-motion were compared by two-way ANOVA (condition x time). All indices of parasympathetic reactivation were compared using a Student\'s t-test. The main results showed that sodium bicarbonate ingestion increased the lactate concentration, estimated glycolytic contribution and total attack time when compared with placebo condition. However, sodium bicarbonate ingestion did not influence heart rate, rate of perceived exertion, estimated oxidative and ATP-PCr contribution during combat simulation compared to placebo. Furthermore, no indices of parasympathetic reactivation were different between sodium bicarbonate and placebo conditions
186

Respostas fisiológicas e análise técnico-tática em atletas de brasilian jiu-jitsu submetidos à luta fragmentada e simulação de competição / Physiological responses and technical-tactical analysis in of Brazilian jiu-jitsu athletes during fragmented fight and during simulated competition

Andreato, Leonardo Vidal 28 February 2014 (has links)
O objetivo deste estudo foi analisar as respostas fisiológicas e realizar análise técnico-tática em atletas de Brazilian jiu-jitsu durante luta fragmenta e simulação de competição. Para isso, 10 atletas foram submetidos a avaliações em luta fragmentada (2 min, 5 min, 8 min e 10 min) e 10 atletas a avaliações em competição simulada (4 combates de 10 min). Foram realizadas coletas sanguíneas (para inferência da demanda energética, respostas hormonais, lesões celulares e equilíbrio hidroeletrolítico), aplicados testes físicos e escalas de percepções de esforço e recuperação. Adicionalmente, os combates foram filmados para análise técnico-tática e determinação da estrutura temporal. Os principais resultados apontam que: (1) nas lutas fragmentas, os combates de maior duração geraram concentrações mais elevadas de lactato e glicose, assim como maior percepção subjetiva de esforço e diminuição da resistência de pegada em teste específico. No entanto, não houve alteração importante da estrutura temporal em nenhum tempo de luta; (2) na competição simulada, os últimos combates apresentaram menores concentrações de lactato, catecolaminas e insulina. Adicionalmente, ocorreram aumentos dos marcadores de lesões celulares nos últimos combates indicando possível dano muscular. A força máxima isométrica de preensão manual apresentou declínio, predominantemente, a partir do terceiro combate. Embora esses dados apontem para a instalação de fadiga, a estrutura temporal dos combates não foi alterada significativamente. As percepções de esforço e recuperação não se alteraram durante a competição simulada. Assim, conclui-se que tempos diferentes de combate resultam em respostas metabólicas diferentes, as quais não produzem alterações importantes de desempenho. No entanto, os combates sucessivos de uma competição geram diminuição gradual da atividade adrenérgica e glicolítica, as quais são acompanhadas de aumento gradual de indicadores de dano celular e diminuição gradual da força de preensão manual / The aim of this study was to analyze physiological responses and perform technicaltactical analysis in Brazilian Jiu-Jitsu athletes during fragmented fight and simulated competition. For that, 10 athletes were submitted to assessment in fragmented fight (2 min, 5 min, 8 min and 10 min) and 10 athletes in simulated competition (4 combats of 10 min). Blood samples were taken (to assess the energy demand, hormonal responses , cell damage and hidroelectrolyte balance) and physical tests and scales of perceptions of effort and recovery were applied. Additionally, the fights were recorded for technical-tactical analysis and to determine the time structure. The main results show that: (1) in the fragmented fight, the longer combats generated higher lactate and glucose concentrations, as well as greater rate of perceived exertion and decreased hand grip endurance in specific test. However, there was no significant change in the time structure in any time of fight, (2) in simulated competitions, the last fights had lower lactate, catecholamines and insulin concentrations. Additionally, increases in markers of cellular damage occurred in the last fights indicating possible muscle damage. The maximal isometric handgrip strength showed decrease predominantly from the third fight. Although these results point to the onset of fatigue, the time structure of the fights was not significantly altered. Effort and recovery perceptions did not change during the simulated competition. Thus, it is concluded that different times of combat result in different metabolic responses which do not produce significant changes in performance. However, successive combats from competition generate gradual decrease of adrenergic and glycolytic activity, which are accompanied by gradual increase of indicators of cellular damage and gradual decrease in handgrip strength
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THE EFFECTIVENESS OF THERAPEUTIC INTERVENTIONS ON SYMPTOMS OF POST TRAUMATIC STRESS DISORDER

Howell, Sean 01 June 2019 (has links)
ABSTRACT Despite a plethora of research documenting the effectiveness of various therapeutic interventions on the symptoms of Post Traumatic Stress Disorder (PTSD), there continues to be ambiguity insofar as which approaches or combination thereof are most effective at improving adverse manifestations of this disorder. This lack of clarity is further confounded when other variables and nuances pertaining to variations of PTSD (i.e. military, sexual trauma, childhood abuse, etc.) are factored into these comparisons. Therefore, the purpose of this study was to explore the impact of various interventions on improving the symptoms of PTSD. This study also examined the variances which stand in need of recognition when determining which interventions are most appropriate and meaningful in improving the quality of life and functionality of individuals with this disorder. This has significance in both macro and micro social work practices due to the potential for improvements in policies, allocation of resources, and enhancements in micro-level interventions. The research design involved qualitative interviews with clinicians devised to identify gaps, areas of agreement, and dissent among the research. Data analysis will be qualitatiive and will be guided by assessing the impact of interventions on the 17 symptoms which, according to the DSM-5 are associated with PTSD.
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College ROTC Cadets' Perceptions of Gender Fairness With Selective Service Registration

Peavie, Barrett 01 January 2018 (has links)
The U.S. Selective Service System currently excludes women from the talent pool based upon the DoD's 1981 ban on women in direct combat. The DoD has removed the exclusion and has implemented a gender-neutral policy standard for assignments. However, there appears to be a misalignment of national security policy as it relates to gender fairness that impacts Reserve Officer Training Corps (ROTC) participants in particular. Using Durkheim's functionalism theory as the theoretical foundation, the purpose of this phenomenological study was to examine institutional differences in policies regarding justice and gender among ROTC participants who are between 18 and 26 years of age in a Middle Atlantic University. Data were acquired through 10 interviews with ROTC members. These data were inductively coded and then subjected to Moustakas and Van Kaam's thematic analysis procedure. Key results included evidence that current policy is misaligned with gender enfranchisement, effective social change requires inclusion of both genders in registration, and a standards-based approach to equality is important to both men and women. This group of future military leaders wants the repeal of male only registration and the inclusion of female citizens as an expression of full citizenship and increased social equity. Further research using this methodological framework in different geographical regions and among different generations could add depth to the current body of knowledge. The implications for positive social change with new Selective Service registration policy would change the process towards registering all young adult citizens in the event of a national emergency which would be the codification of fairness and value for all citizens in public policy.
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Combat Service and Posttraumatic Stress Disorder as a Violent Crimes Predictor in OEF/OIF Veterans

Ivory, Rachel L. 01 January 2017 (has links)
There is an established link between posttraumatic stress disorder (PTSD) and criminal activity. Of every 100 veterans who served during Operation Enduring Freedom (OEF)/Operation Iraqi Freedom (OIF), 11 to 20 percent are diagnosed with PTSD each year. Previous research has documented that veterans are incarcerated at higher percentages compared to nonveteran inmates, though little published research examines incidence of PTSD relative to violent crime. Using Agnew's general strain theory as the foundation, the purpose of this correlational study was to examine combat service, PTSD, and specific violent crimes as defined by the FBI as murder and nonnegligent manslaughter, forcible rape, robbery, and aggravated assaults; while controlling for branch of service, age, and sex. The sample consisted of 46 OEF/OIF inmates (federal and state) 9 of whom were convicted of a violent crime. Results from the multiple logistic regression analysis showed that combat service, PTSD, sex, and branch of service were not statistically significant predictors of imprisonment of OEF/OIF veterans for violent crime. Age, however, was statistically significant p = .029. The findings of this study contribute to social change by providing policymakers and prison administrators nuanced information (i.e., characteristic information - age, sex, branch of service, etc.) about the needs of this unique prison population with regards to reintegration. This may in turn contribute to improved reintegration initiatives to enrich the lives of veterans, their families, and the communities where veterans reside when returning from war. Focusing on reintegration will be very beneficial.
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Conception et modélisation d'un système de mesure de la force d'impact dans les Sports de Combat et les Arts Martiaux / Conception and modelling of a measure system of impact force in Fighting Sports and Martial Arts

Girodet, Pascal 27 March 2012 (has links)
L’objectif de cette thèse était d'évaluer la force d’impact dans des conditions proches de la pratique des Sports de Combat et des Arts Martiaux (SCAM) à l'aide d'un ergomètre composé d’un bloc-cible instrumenté avec un accéléromètre et un dynamomètre, et monté sur une lame flexible fixée verticalement sur le sol. La force d'impact a été calculée à partir des trois composantes mesurées par le dynamomètre, d'une part, et à partir de l'accélération du bloc-cible, grâce à un modèle mécanique original, d'autre part. Les mesures dynamiques ont été associées à des mesures cinématiques 3D à haute vitesse afin de caractériser les gestes de frappe de quatre boxeurs en situation d'entraînement, et d'en identifier les paramètres d'optimisation : gamme des énergies cinétiques pic et incidente du membre supérieur, gamme des pics de force d’impact, et forces intra articulaires au poignet, au coude et à l'épaule, calculées par dynamique inverse. Parallèlement, l’évaluation mécanique de quelques protections de boxe française (gants et bandages) et de karaté (gants, protège-pieds et protège-tibias) a montré que le test défini par la norme NF EN 13277-2 était insuffisant pour caractériser leurs propriétés amortissantes. Les résultats des mesures en situation et en laboratoire ont mis en évidence la qualité discutable de certains gants de boxe française et l'absence d’effet protecteur des bandages. La Fédération Française de Boxe Française (FFSBFDA) doit encore tirer toutes les conclusions de ces résultats. Les résultats des protections de karaté ont permis à la Fédération Française de Karaté (FFKDA) d'en définir les caractéristiques souhaitables, qui ont été approuvées par la Fédération Mondiale de Karaté (WKF). Au-delà de ces conséquences pratiques, la cible-ergomètre conçue, fabriquée et mise en oeuvre dans cette thèse, et le modèle mécanique associé présentent des avantages expérimentaux et ergonomiques qui ouvrent des perspectives d’évaluation de la force d'impact de nombreuses techniques de frappe utilisées dans les Sports de Combat et les Arts Martiaux. / The purpose of this thesis was to assess the impact force in conditions close to the practice of Fighting Sports and Martial Arts using an ergometer composed of a target-block instrumented with an accelerometer and a dynamometer, and mounted on a flexible lath vertically fixed on the floor. The impact force was computed from the three components measured by the dynamometer, and also from the acceleration of the target-block, using an original mechanical model. The dynamic measurements have been combined with those of a 3-D high speed kinematic analysis in order to characterize the striking movements of four French Boxers in training conditions, and to identify their optimization parameters : range of maximal and incident linear kinetic energies, range of impact force peaks, and joint forces at the wrist, the elbow and the shoulder, computed by inverse dynamics. Concurrently, the mechanical evaluation of some protective gears for French Boxing (gloves and handwraps) and Karate (gloves, leg-protections and shin protections) has shown that the test defined by the NF EN 13277-2 norm was not sufficient for assessing their damping properties. The results of practice and laboratory measurements exhibited the doubtful quality of some French Boxing gloves and the lack of damping effect of handwraps. The French Federation of French Boxing (FFSBFDA) should still draw all the conclusions of these results. The results of the Karate protective gears have allowed the French Karate Federation (FFKDA) to define their desirable characteristics, which have been approved by the World Karate Federation (WKF). Beyond these practical outcomes, the striking ergometer, designed, built and used in this thesis, and the associated mechanical model have / possess experimental and ergonomic advantages, which open wide perspectives for assessing the impact force of many striking techniques used in Fighting Sports and Martial Arts.

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