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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.
31

Predição da intensidade de corrida em máxima fase estável de lactato a partir da velocidade de crítica em atletas fundistas de alto rendimento: relações com performances

D'Angelo, Ricardo Antonio [UNESP] 01 July 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-01Bitstream added on 2014-06-13T19:28:23Z : No. of bitstreams: 1 dangelo_ra_me_rcla.pdf: 444962 bytes, checksum: 9e4977bddba15cb8009dd5428d72ccc4 (MD5) / Universidade Estadual Paulista (UNESP) / A corrida de longa distância é considerada um fenômeno sócio-esportivo recente e de grande impacto na vida moderna. No segmento dos atletas profissionais, a busca por índices confiáveis de avaliação aeróbia, bem como programas de treinamento eficazes e de fácil aplicabilidade é contínua. O tema central desse trabalho foi fornecer uma ferramenta adequada e precisa para se determinar o atual estado da forma do atleta de fundo de alto rendimento, bem como predizer intensidades de carga confiáveis para treinamento e competição. Para tanto, foi estabelecida uma relação matemática entre dois testes de avaliação aeróbia: Máxima Fase Estável de Lactato (MFEL) e Velocidade Crítica (Vcrit). Nove atletas fundistas de alto rendimento, que participaram de seleções nacionais em competições internacionais, tomaram parte no experimento. As melhores marcas pessoais desses atletas correspondem à média ± erro padrão de 91,54 ± 0,93 % da velocidade de corrida do recorde mundial (considerados até o ano de 2007) de sua prova específica. Os testes foram realizados na fase final do período de treinamento de preparação geral. Inicialmente foi aplicado o teste de Vcrit nas distâncias de 800m, 1500m, 3.000m e 5.000m, realizadas aleatoriamente e em dias subseqüentes. A seguir, foi aplicado o teste clássico de MFEL, com duração de 30 min de corrida contínua e coleta de amostras de sangue (25μL) a cada 5 min, para determinação das concentrações de lactato (YSI 1500 sport). Para oito atletas a MFEL ocorreu na intensidade correspondente a 98% da Vcrit, sendo o restante obtido a 90% da Vcrit. A Vcrit (19,1±0,1 km/h) superestimou (p=0,005) os valores de MFEL (18,7±0,2 km/h). Houve correlação significativa entre Vcrit e MFEL (p=0,002, r=0,88). A equação obtida pela regressão foi MFEL=0,9673*Vcrit+0,2061, com erro padrão da estimativa de 0,236... / The purpose of this study was to establish a mathematical relationship between the MLSS and the critical speed (CS) in high performance distance runners. Nine male high performance athletes were tested (28±2years), with personal bests of their specific events corresponding a mean ± ESE of 91,54 ± 0,93 % of world record running speed (updated 2007). The athletes were submitted to the CS test, which is the linear regression of the distances (800, 1.500, 3.000 and 5.000m) and their respective time. The CS was determined by the angular coefficient of the linear regression. For all athletes, the regression coefficient (R2) was equal to 1,0. The predicted workloads for the MLSS determination were: 100, 98, 95 and 90% of the CS, randomized and in a continuous way in subsequent days. In this test, the athletes run for 30 min, and it was collected blood samples (25μL) at each 5 min, to determine the lactate concentration (YSI 1500 sport). It was determined stable the non lactate variation higher than 1,0 mmol/L between the 10th and 30th minute. The MLSS has occurred for 8 athletes on the 98% intensity of CS and for 1 athlete on the 90%. The CS (19,1±0,1 km/h) overestimated (p=0,005) the MLSS values (18,7±0,2 km/h). There was significant correlation between CS and MLSS (p=0,002, r=0,88). The regression equation was MLSS=0,9673*CS+0,2061, with estimated standard error of 0,236. There was excellent application of distances to determine the CS in elite distance runners, as well as the parameter accuracy to the “gold standard” intensity verified with the MLSS test. These responses, associated with the low standard estimated error, suggest safety at the MLSS determination through the predicted equation proposed.
32

Efeitos do treinamento pliométrico em variáveis fisiológicas e neuromusculares de corredores de longa distância / Effects of plyometric training on physiologic and neuromuscular variables of long distance runners

João Paulo Vieira Manechini 27 April 2017 (has links)
Com o objetivo de comparar os efeitos do treinamento de força rápida em parâmetros fisiológicos, mecânicos e neuromusculares de corredores de fundo, o presente trabalho contou com uma amostra de 18 atletas amadores do sexo masculino, praticantes de corrida de rua e com experiência em provas de longa distância (21km ou acima). A amostra foi selecionada para o grupo \"treinamento de força rápida\", (RPG - grupo experimental) ou \"exercícios educativos técnicos de corrida\" (RTG - grupo controle), que realizaram seis semanas de exercícios distintos. No intuito de avaliar o desempenho em variáveis-chave para o rendimento de fundistas, os sujeitos foram submetidos a uma série de testes em dois momentos distintos: após a semana de aprendizagem e adaptação aos exercícios (pré) e ao final das seis semanas dos protocolos propostos (pós). A bateria de testes foi composta por: testes de saltos verticais (Altura [H], Potência Pico [PP] e Potência Relativa [PR] do salto para as técnicas Squat Jump [SJ], Counter Movement Jump [CMJ] e Drop Jump 40cm [DJ40]); salto horizontal [SH] e salto sêxtuplo alternado [S6A] (distância saltada); uma repetição máxima no agachamento guiado (carga absoluta [1RM Abs.] e relativa à massa corporal [1RM Rel.]); teste de contração isométrica voluntária máxima (CIVM - força pico [Fpico], força pico relativa à massa corporal [Fpico R.], tempo da força pico [TFPICO] e taxa de desenvolvimento de força [TDF]); teste incremental de esteira (Velocidade Pico em Esteira [VPE] e Velocidade do Limiar de Lactato [vLL]); e tempo limite em esteira na VPE (Tlim). O tratamento estatístico foi realizado por meio do Software IBM® SPSS® Statistics v. 20.0, para Windows (IBM Corporation, Chicago, USA). A ANOVA Modelo Misto foi utilizada para as comparações das variáveis de desempenho entre momentos e entre grupos, com teste post-hoc de Bonferroni quando necessário, e o teste t de Student para amostras independentes foi realizado para comparar as variáveis relativas ao treinamento entre os grupos. Todas as variáveis foram submetidas aos testes estatísticos Cohen\'s \"d\" de Magnitude de Efeito (ES) e Probabilidade Quantitativa de Chances (QC). Foram encontradas diferenças estatisticamente significantes para as variáveis Altura de Salto e Potência Relativa para a técnica de salto vertical Squat Jump entre os momentos pré e pós treinamento para o grupo RPG (HSJ: F = 6,973; p = 0,018; PRSJ: F = 8,421; p = 0,01) e Altura de Salto e Potência Relativa para a técnica de salto vertical Counter Movement Jump entre os grupos RPG e RTG, após as seis semanas de exercícios (HCMJ: F = 6,163; p = 0,025; PRCMJ: F = 4,667; p = 0,046). Foi identificada diferença significativa para a variável \'tempo da Fpico\' (F = 7,731; p = 0,013) durante o teste de CIVM para o grupo RPG entre os momentos. O grupo Controle, ainda, apresentou queda na variável VPE após as seis semanas do protocolo (F = 5,493; p = 0,032), o que não foi observado no grupo Pliometria. Ademais, o grupo experimental apresentou redução nos valores de lactato sanguíneo nos minutos 1, 3 e 5 após o teste de Tlim (F = 16,858; p = 0,001; F = 8,406; p = 0,01; F = 12,092; p = 0,003, respectivamente). É possível concluir que o treinamento pliométrico foi superior ao protocolo de exercícios educativos no intuito de melhorar o desempenho da força rápida de membros inferiores, contribuindo, ainda, para a manutenção dos níveis iniciais de desempenho em corrida e a melhora da remoção do lactato sanguíneo, o que não pode ser observado no grupo RTG. / With the purpose to compare the effects of explosive-strength training in physiologic and neuromuscular variables of endurance runners, the present study accounted with 18 male amateur athletes experienced in long distance races (21km and above). The sample was divided between explosive-strength training - RPG (running plyometrics group) and technique exercises protocol - RTG (running techniques group), which performed six weeks of distinct exercise protocols. With the aim to evaluate key-variables for endurance running performance the subjects were submitted to batteries of assessments in two different moments: after the exercises adaptation week and right before the beginning of the protocols, and at the end of the exercise protocols. The assessments battery contained vertical jump tests (Jump Height [H], Peak Power [PP] and Relative Power [RP] for the techniques Squat Jump [SJ], Counter Movement Jump [CMJ] and Drop Jump 40cm [DJ40])/ horizontal long jump (SH) and sextuple jump alternating legs (S6A), one maximum repetition for squat at Smith Machine (absolute [1RM Abs.] and relative to body mass loads [1RM Rel.]), maximum voluntary isometric contraction test (MVIC - peak force [Fpico], peak force relative to body mass [Fpico R.], time to peak force [TFPICO] and rate of force development [TDF]); maximum incremental treadmill test (treadmill peak velocity [VPE] and lactate threshold velocity [vLL]), and time limit test at treadmill peak velocity (Tlim). The statistical procedures were performed at IBM® SPSS® Statistics Software v. 20.0, para Windows (IBM Corporation, Chicago, USA) The Mixed Model ANOVA was performed with dependent variables to identify time and group interactions, using the Bonferroni post-hoc test when necessary, while the training variables were analyzed by the Student\'s t test for independent samples. All data were also analyzed with Cohen\'s \"d\" Effect Size test (ES) and Probability of Quantitative Chances (QC). There were found in RPG significant differences for H and PR for Squat Jump technique between moments pre- and post-protocol (HSJ: F = 6,973; p = 0,018; PRSJ: F = 8,421; p = 0,01), and for the same variables for Counter Movement Jump technique between RPG and RTG (HCMJ: F = 6,163; p = 0,025; PRCMJ: F = 4,667; p = 0,046) after the exercise protocols. Also, significant difference was found for \'time to peak force\' variable (F = 7,731; p = 0,013) during the MVIC test for the group RPG between moments. Yet, the control group presented significant decrease of peak treadmill velocity in the moment post- compared to the pre-training (F = 5,493; p = 0,032), which was not observed in the experimental group. Still, the experimental group presented lower values for lactate concentrations 1, 3 and 5 minutes after Tlim test (F = 16,858; p = 0,001; F = 8,406; p = 0,01; F = 12,092; p = 0,003, respectively). It is possible to conclude that the plyometric training performed by the RPG was superior to the technique exercises protocol in the objective of increasing lower-limbs explosive-strength parameters, contributing to the maintenance of running performance and a better lactate clearance capacity, which did not happen in the RTG.
33

Exploring the uses of mental skills by competitive road running athletes

Ngobese, Khayelihle Mbongeleni Emmanuel January 2015 (has links)
Research on athletes has shown that mental skills are an important component of being a successful athlete. The importance of these mental skills is seen in the number of athletes who have formally started training using mental skills training programmes (MST) according to the literature. The study of mental skills in South Africa lags behind other countries like USA, UK and Sweden. This particular study explored the use of mental skills by road running athletes. The study was conducted with six competitive marathon athletes. Semi-structured interviews were conducted as part of an elaborate qualitative methodology design. The data collected from these semi-structured interviews was analysed using thematic analysis. The results show that road running athletes use mental skills that include; mental rehearsal, planning, goal setting and self-talk. The athletes in this research showed the importance of mental skills and it is recommended that formal training in these mental skills will be highly beneficial not only to road running athletes but for all South African sports people in general
34

Psychological aspects of long-distance running among South African marathon runners

Symonds, Genevieve 11 1900 (has links)
The purpose of this study was to determine why South African long-distance runners start and continue to run long distances, what perceived psychological benefits and negative effects they experience as a result of their involvement in the sport, and what thoughts and emotions are associated with the runner's high. Questionnaires were sent to 2 000 1992 Two Oceans Marathon participants and 777 responded. Results show that South African long-distance runners start running chiefly for physical fitness and health reasons, and continue for these reasons as well as psychological benefit reasons. As a result of their involvement in the sport, they experience psychological benefits such as a positive mood, positive self-image and positive mental outlook. When unable to run, these benefits are reversed. They also experience negative effects such as relationship problems because of long-distance running. Many thoughts and emotions are associated with the runner's high, but most define it as an euphoric feeling / Art History, Visual Arts & Musicology / M.A. (Psychology)
35

Efeito comparativo de repositores energéticos sobre as concentrações plasmáticas de glicose e ácidos graxos livres de corredores de longa distância / Comparative effects of energetic repositors on plasma free-fatty acids and glucose of long distance runners

Ribeiro, Beatriz Gonçalves 12 August 2004 (has links)
A reposição de glicogênio pós treino foi investigada usando uma mistura de ambos, glicose e glicose-frutose, como repositores, em atletas corredores de longa distância. Dez corredores competitivos (30±4,7 anos) foram avaliados para composição corporal e consumo alimentar antes do exercício de 90 minutos em esteira elétrica a 70% V02máx. Amostras de sangue venoso foram coletadas antes e após o término do exercício, quando eles receberam 1g de carboidrato.kg-1 de uma mistura de ambos, glicose-frutose (CHO1) e glicose (CHO2), e outra com sucralose ou placebo (controle). Amostras de sangue foram retiradas 30, 60, 90 e 120 minutos após o consumo dos suplementos e usadas para determinação de glicose e de ácidos graxos plasmáticos, por reações colorimétricas. Não foram observadas diferenças significativas na composição corporal e na hidratação durante o exercício. Os tratamentos CHO1 e CHO2 produziram elevação na glicemia, em 30 minutos, comparados ao grupo placebo. Entretanto, em 90 min, somente no tratamento CHO1, uma queda na glicemia foi observada (CHO2>CHO1). Os ácidos graxos livres aumentaram comparativamente após o exercício (CHO1=CHO2=placebo) e, diferente do placebo, em 90 minutos, reduziram nos tratamentos CHO1 e CHO2. Ambos os repositores atuaram similarmente nas concentrações de ácidos graxos livres, mas o declínio da glicose plasmática (remoção da glicose) ocorreu primeiramente com o tratamento glicose-frutose do que com o glicose. Assim, a mistura glicose-frutose parece promover uma reposição de glicogênio mais rápida após exercícios de longa duração. / The post training glycogen replacement was investigated using either glucose or glucose-fructose mixture as repositors in long-distance athletes. Ten males (30±4,7yrs) voluntary competitive long distance runners were assessed for body composition and dietary intake prior to a 90 min 70% vo2 max exercise in treadmill. Blood samples were collected before and after the exercise when they received orally 1g of CHO.kg-1 either as maltodextrin-glucose-fructose (CHO1) or maltodextrin - glucose (CHO2) mixtures, having sucralose or placebo (control). Blood samples were drawn 30,60, 90 and 120 minutes after supplement intake and used for plasma glucose and free-fatty acids determinations by colorimetric reactions. There were no significant changes on body composition, mass or hydration, during the treadmill exercise. CHO1 and CHO2 loading increased the 30 min blood glucose both significatively above the placebo. However at 90 min only CHO1 decreased significantily (CHO2>CHO1). The FFA increased comparatively (CHO1=CHO2=placebo) after exercise and differently from placebo CHO1 and CHO2 decreased (similarly) up to 90 min. Both energetic repositors acted similarly on FFA levels but the plasma glucose decreasing (glucose removal) occurred earlier with glucose-fructose loading rather than glucose alone. Thus glucose-fructose mixtures seems to promote faster glycogen repletion after long lasting aerobic exercises.
36

Efeito comparativo de repositores energéticos sobre as concentrações plasmáticas de glicose e ácidos graxos livres de corredores de longa distância / Comparative effects of energetic repositors on plasma free-fatty acids and glucose of long distance runners

Beatriz Gonçalves Ribeiro 12 August 2004 (has links)
A reposição de glicogênio pós treino foi investigada usando uma mistura de ambos, glicose e glicose-frutose, como repositores, em atletas corredores de longa distância. Dez corredores competitivos (30±4,7 anos) foram avaliados para composição corporal e consumo alimentar antes do exercício de 90 minutos em esteira elétrica a 70% V02máx. Amostras de sangue venoso foram coletadas antes e após o término do exercício, quando eles receberam 1g de carboidrato.kg-1 de uma mistura de ambos, glicose-frutose (CHO1) e glicose (CHO2), e outra com sucralose ou placebo (controle). Amostras de sangue foram retiradas 30, 60, 90 e 120 minutos após o consumo dos suplementos e usadas para determinação de glicose e de ácidos graxos plasmáticos, por reações colorimétricas. Não foram observadas diferenças significativas na composição corporal e na hidratação durante o exercício. Os tratamentos CHO1 e CHO2 produziram elevação na glicemia, em 30 minutos, comparados ao grupo placebo. Entretanto, em 90 min, somente no tratamento CHO1, uma queda na glicemia foi observada (CHO2>CHO1). Os ácidos graxos livres aumentaram comparativamente após o exercício (CHO1=CHO2=placebo) e, diferente do placebo, em 90 minutos, reduziram nos tratamentos CHO1 e CHO2. Ambos os repositores atuaram similarmente nas concentrações de ácidos graxos livres, mas o declínio da glicose plasmática (remoção da glicose) ocorreu primeiramente com o tratamento glicose-frutose do que com o glicose. Assim, a mistura glicose-frutose parece promover uma reposição de glicogênio mais rápida após exercícios de longa duração. / The post training glycogen replacement was investigated using either glucose or glucose-fructose mixture as repositors in long-distance athletes. Ten males (30±4,7yrs) voluntary competitive long distance runners were assessed for body composition and dietary intake prior to a 90 min 70% vo2 max exercise in treadmill. Blood samples were collected before and after the exercise when they received orally 1g of CHO.kg-1 either as maltodextrin-glucose-fructose (CHO1) or maltodextrin - glucose (CHO2) mixtures, having sucralose or placebo (control). Blood samples were drawn 30,60, 90 and 120 minutes after supplement intake and used for plasma glucose and free-fatty acids determinations by colorimetric reactions. There were no significant changes on body composition, mass or hydration, during the treadmill exercise. CHO1 and CHO2 loading increased the 30 min blood glucose both significatively above the placebo. However at 90 min only CHO1 decreased significantily (CHO2>CHO1). The FFA increased comparatively (CHO1=CHO2=placebo) after exercise and differently from placebo CHO1 and CHO2 decreased (similarly) up to 90 min. Both energetic repositors acted similarly on FFA levels but the plasma glucose decreasing (glucose removal) occurred earlier with glucose-fructose loading rather than glucose alone. Thus glucose-fructose mixtures seems to promote faster glycogen repletion after long lasting aerobic exercises.
37

Psychological aspects of long-distance running among South African marathon runners

Symonds, Genevieve 11 1900 (has links)
The purpose of this study was to determine why South African long-distance runners start and continue to run long distances, what perceived psychological benefits and negative effects they experience as a result of their involvement in the sport, and what thoughts and emotions are associated with the runner's high. Questionnaires were sent to 2 000 1992 Two Oceans Marathon participants and 777 responded. Results show that South African long-distance runners start running chiefly for physical fitness and health reasons, and continue for these reasons as well as psychological benefit reasons. As a result of their involvement in the sport, they experience psychological benefits such as a positive mood, positive self-image and positive mental outlook. When unable to run, these benefits are reversed. They also experience negative effects such as relationship problems because of long-distance running. Many thoughts and emotions are associated with the runner's high, but most define it as an euphoric feeling / Art History, Visual Arts and Musicology / M.A. (Psychology)

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