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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.
831

Estudo molecular dos genes alfa actinina 3 e ECA I/D em atletas de esportes de combate, artes marciais e lutas de alto rendimento: ênfase em luta de percussão

Netto, Zair Candido de Oliveira 17 November 2014 (has links)
Os fatores genéticos e o meio ambiente são pontos relevantes no que tange a capacidade física do ser humano. O objetivo deste estudo foi avaliar o genótipo dos genes, ACTN3 e da ACE I/D, em lutadores de alto rendimento na modalidade de percussão. Neste estudo fizeram parte do conjunto amostral 15 atletas de alto rendimento da esportes de combate e arte marcial, sendo sendo 6 lutadores de Karatê, 4 lutadores de Taekwondo, 4 lutadores de Muay Thai e 1 lutador de Boxe, todos do sexo masculino com idade média de 25,06 anos, com experiência nacional e internacional em suas respectivas modalidades e categorias de peso. A genotipagem dos polimorfismos do ACTN3 e ACE I/D foi realizada por reação em cadeia da polimerase (PCR) a partir do DNA genômico. As frequências genotípicas e alélicas foram comparadas com populações controle e de atletas pelos testes do Qui-Quadrado, e exato de Fisher, para todas as análises foi adotado p˂0,05. Os resultados obtidos para as frequências genotípicas e alélicas do ACTN3 (RR=35,71%,RX=57,14% e XX=7,14%; R=64,28% e X=33,71%) e do ACE I/D (DD=30,76%, ID=50,84% e II=15,36%; D=65,2% e I=34,8%) não diferiram significativamente da população controle e com estudos relacionados a força. Em conclusão os dados da presente pesquisa seguem os padrões esperados para população no que tange a frequência genotípicas e em sua distribuição alélica nos genes da ACTN3 e da ACE I/D com lutadores de percussão. / Genetic factors and the environment are relevant points regarding the physical capacity of the human being. The objective of this study was to evaluate the genotype of genes, ACTN3 and ACE I / D with fighters in high yield in the form of percussion. In this study were part of the sample set of 15 high-level athletes in combat sports and martial arts, 6 fighters from Karate, 4 fighters Taekwondo, 4 fighters Muay Thai and 1 boxing. All fighters being present, all males with average age of 25.06 years with national and international experience in their respective weight classes and methods. Genotyping of polymorphisms of ACTN3 and ACE I / D was performed by polymerase chain reaction (PCR) chain from the genomic DNA. The genotypic and allelic frequencies were compared with control populations and athletes by Qui-Quadrado and Fisher exact tests for all analyzes was adopted P=0.05. The results obtained for genotypic and allelic frequencies of ACTN3 (RR = 35.71%, 57.14% and RX = XX = 7.14%; R = X = 64.28% and 33.71%) and ACE I / D (DD = 30.76%, 50.84% and ID = II = 15.36%; D = I = 65.2% and 34.8%) did not differ significantly from the control population e power sports In conclusion the data of this study follow the expected population in relation to genotypic and allelic frequency distribution in the ACTN3 gene and ACE I / D fighters of percussion.
832

Modelagem eletroquímica e do distúrbio ácido-básico em atletas de karatê participantes do campeonato mundial WKO 2014 / Electrochemical and acid-base disorder evaluation in Karate athletes participating in the world championship WKO 2014

Ferreira, Lucas dos Santos 04 December 2015 (has links)
O objetivo deste estudo foi avaliar o comportamento eletroquímico e do distúrbio ácido-básico em atletas de alto rendimento durante o campeonato mundial de Karatê realizado pela WKO (World Karate Organization) em 2014. A amostra foi composta por 19 atletas do gênero masculino, com idade média de 34 ± 8 anos. Todos eles eram faixas pretas, e tinham mais de 5 anos de prática na modalidade. Foram realizadas coletas de sangue capilar da polpa digital dos dedos da mão em três momentos: repouso, 5 minutos após o combate e 10 minutos após combate (kumite). A amostra foi analisada utilizando o aparelho de gasometria GEM Premier 3000, utilizando os parâmetros pH, Na+, K+, Ca2+, lactato e HCO3−. Os valores relacionados ao distúrbio ácido-básico apresentaram diferenças estatísticas (p<0,05) na maioria dos momentos coletados. Os valores de lactato encontrados foram de 2,77 ± 0,97 mmol/L no repouso, 6,57 ± 2,1 para 5 minutos após e de 4,06 ± 1,55 para 10 minutos após o combate. Os dados coletados relativos aos marcadores eletrolíticos não apresentaram diferenças estatísticas em seus valores (p<0,05). Através dos dados levantados, conjecturamos que a modalidade pode ser caracterizada como exercício de alta intensidade e com predominância do sistema glicolítico. A análise do distúrbio ácido-básico é uma medida eficiente para auxiliar no controle das cargas de treinamento. / The objective of this study was to analyze the electrochemical and acid-base disorders in high performance athletes during the World Karate Championship hosted by the WKO (World Karate Organization) in 2014. In this study 19 male athletes were analyzed (age 34 ± 8), black belts and with over 5 years of experience in the sport. Capillary blood samples from the digital pulp of the finger were collected in three stages: rest, 5 minutes after and 10 minutes after fighting (kumite). The sample was analyzed using blood gas analyzer GEM Premier 3000, using the parameters pH, Na+, K+, Ca2+, lactate e HCO3−. The values related to acid-base disturbance presented statistical differences (p <0.05) in most of the collected moments. The lactate levels found were 2.77 ± 0.97mmol / L in rest, 6.57 ± 2.1 for 5 minutes after and 4.06 ± 1.55 for 10 minutes after combat. The samples collected for the electrolytic markers showed no statistical differences in their values (p <0.05). Through the data collected, we conjecture that the sport can be characterized as a high-intensity exercise and with a predominance of the glycolytic system. The analysis of acid-base disturbance is an efficient method to assist in the control of training loads.
833

Prevalência dos sintomas de asma e alergia e avaliação dos mecanismos envolvidos no broncoespasmo induzido pelo exercício em corredores de longa distância / Prevalence of asthmatic and allergic symptoms and mechanism of exercise-induced bronchoconstriction in long distance runners

Renata Nakata Teixeira 07 May 2014 (has links)
A prevalência de sintomas de asma, broncoespasmo induzido pelo exercício (BIE), hiperresponsividade brônquica (HRB) e alergia em atletas que praticam modalidades de alto rendimento e longa duração tem aumentado nas últimas décadas e tem sido estudada principalmente em atletas de inverno e nadadores. No entanto, a prevalência de sintomas de asma e alergia e os mecanismos inflamatórios envolvidos no BIE que ocorre em corredores de longa distância permanecem pouco conhecidos. Objetivos: O presente estudo tem como objetivo avaliar a prevalência de sintomas de asma e alergia em corredores de longa distância de elite e investigar os mecanismos inflamatórios envolvidos no BIE nos atletas sem histórico de asma. Casuística e Métodos: Este estudo foi realizado em duas fases: na Fase I, foi avaliada a prevalência de sintomas de asma e alergia em 201 corredores de longa distância, através da aplicação dos questionários ISAAC e AQUA©. Na Fase II, foram avaliados os mecanismos inflamatórios envolvidos no BIE de 40 corredores que não apresentaram sintomas de asma na Fase I e que foram selecionados aleatoriamente. Nesta fase, os atletas compareceram ao laboratório em três momentos, com intervalo máximo de duas semanas entre cada visita, e foram submetidos às seguintes avaliações 1º) escarro induzido e teste cardiopulmonar máximo, 2º) broncoprovocação por metacolina e, 3º) óxido nítrico no ar exalado (FeNO), metabólitos LTE4 e 9alfa, 11beta-PGF2 e teste de hiperventilação eucápnica voluntária (HEV). Resultados: A prevalência de sintomas de asma e alergia foi de 6,5% e 60,5%, respectivamente. Ao analisar as questões do AQUA©, observou-se alta frequência de sintomas de BIE (62,3%) e rinite (56,6%). Os sintomas de alergia não foram associados a variáveis como gênero, idade, experiência em corridas de longa distância, volume de treinamento semanal e desempenho em provas de meia maratona e maratona. Verificou-se ainda que a prevalência de BIE foi de 27,5%. Quando comparados os atletas BIE+ e BIE- não foram observadas diferenças nos valores de VEF1 absoluto, nas medidas antropométricas, nas características de treinamento e também no desempenho. Os atletas BIE+ relataram mais sintomas de alergia (p=0,03), se mostraram mais responsivos à metacolina (p=0,01), apresentaram maior porcentagem de eosinófilos no escarro (p=0,03) e níveis mais elevados de FeNO (p < 0,001*) quando comparados aos atletas BIE-. Os níveis urinários de LTE4 e 9alfa, 11beta-PGF2 basais e após 60 minutos do teste de HEV foram similares entre os grupos BIE+ e BIE-, no entanto, ao comparar os níveis destes mediadores antes e após o teste de HEV, observou-se uma diminuição nos níveis de LTE4, apenas nos atletas BIE- (p=0,04). Conclusões: Corredores de longa distância apresentam elevada prevalência de sintomas de alergia e BIE e baixa prevalência de sintomas de asma. Além disto, os atletas BIE+ referem mais sintomas de alergia, são mais hiperresponsivos à metacolina, apresentam um padrão inflamatório eosinofílico e elevados níveis de FeNO embora sem diferenças nos níveis basais dos metabólitos do mastócito / An increased prevalence of asthma and allergic symptoms, exercise-induced bronchoconstriction (EIB) and bronchial hyperresponsiveness (BHR) has been observed in elite and endurance athletes, especially winter sports athletes and swimmers. However, the occurrence of allergy symptoms and the inflammatory mechanisms involved in the EIB that occurs in long distance runners remains poorly known. Objectives: the aims of the present study were to assess the prevalence of symptoms of asthma and allergy in long distance runners and to investigate possible inflammatory mediators involved in the EIB that occurs in those without asthma history. Methods: This cross sectional study was performed in two phases. In Phase I, the prevalence of symptoms of asthma and allergy was assessed in 201 long distance runners using ISAAC and AQUA© questionnaires. In Phase II, 40 athletes were randomly selected among those who did not present asthma history and they performed the following measurements: induced sputum, cardiopulmonary exercise testing, methacholine bronchoprovocation challenge, exhaled nitric oxide (FeNO), urinary collection to quantify LTE4 and 9alfa, 11beta-PGF2 metabolites and eucapnic voluntary hyperventilation test (EVH). Results: The prevalence of asthma and allergy symptoms was 6.5% and 60.5%, respectively. In addition, we observed a high frequency of EIB symptoms (62.3%) and rhinitis (56.6%). Allergy symptoms were not associated with anthropometric characteristics, running experience, weekly training volume and best half-marathon and marathon performance. The prevalence of EIB was 27.5% and no difference in baseline lung function, anthropometric data as well as training and performance characteristics was observed between athletes with (EIB+) and without (EIB-) EIB. EIB+ athletes reported more allergy symptoms (p=0.03) and were more resposive to methacholine (p=0.01) than EIB- athletes. A higher percentage of eosinophils in the induced sputum (p=0.03) and levels of FeNO (p < 0.001*) were observed in EIB+ athletes. However, there was no difference in the urinary levels of LTE4 and 9alfa, 11beta-PGF2 either at baseline or after EVH test. Conclusions: Long distance runners have a high prevalence of allergy symptoms and EIB and a low prevalence of asthma symptoms. Moreover, EIB+ athletes report more symptoms of allergy and present airway hyperresponsiveness, eosinophilic inflammation and increased levels of exhaled nitric oxide, without difference in the baseline levels of mast cell metabolites
834

Análisis de los procesos en la comunicación corporativa de los clubes profesionales de Lima: estudio exploratorio

Peláez-Alegría, Pierre-Dereck January 2016 (has links)
El fútbol peruano atraviesa una crisis institucional, económica y deportiva a consecuencia de la informalidad con la que han sido gestionados los clubes deportivos locales. Sin embargo, no se necesita ir muy lejos para comprobar que las entidades deportivas, gestionadas adecuadamente, y adaptando herramientas del ?management? a sus modelos de negocio, entre los que destaca la comunicación corporativa, han logrado convertirse en instituciones sólidas, reputadas y exitosas. En ese sentido, resulta preciso advertir cuál es el valor que se le da al corporate en dos de los clubes de fútbol más sólidos del campeonato local (Sporting Cristal y la Universidad San Martín de Porres); del mismo modo, es oportuno conocer la forma en la que se viene desarrollando la comunicación en ambas instituciones; lo cual permitirá realizar una primera aproximación al estado de esta importante herramienta del management en las entidades deportivas nacionales. / Trabajo de investigación
835

Physiological and performance adaptations to altitude and hypoxic training

Holliss, Ben Alaric January 2014 (has links)
Introduction: There have been few well controlled altitude and hypoxic training studies to date. This thesis investigated the effects of altitude and (sham controlled) intermittent hypoxic training (IHT) on exercise capacity, and the associated physiological adaptations. Methods: Chapter 3 investigated how living and training at 2320 m or at sea level affected total haemoglobin mass (tHb) and race performance in highly trained swimmers. Chapter 4 investigated how IHT or normoxic training affected cardiopulmonary variables and the incremental exercise limit of tolerance (T-Lim), in highly trained runners. Chapter 5 investigated how single-legged IHT or normoxic training affected phosphorus-31 nuclear magnetic resonance spectroscopy assessed muscle energetics. Results: In Chapter 3, tHb increased significantly more after altitude (+0.6 ± 0.4 g•kg-1, or +4.4 ± 3.2%) than after sea level (+0.03 ± 0.1 g•kg-1, or +0.3 ± 1.0%), but the changes in swimming performances were not different between groups, and there were no correlations between tHb and performance changes. In Chapter 4, submaximal heart rate in normoxia decreased significantly more after IHT than after normoxic training (-5 ± 5 vs. -1 ± 5 b∙min-1), and submaximal "V" ̇O2 in hypoxia significantly decreased, only after IHT. T-Lim in hypoxia significantly increased post-IHT, but there were no between group differences. In Chapter 5, the phosphocreatine recovery time constant was speeded significantly more in the IHT compared to the normoxic trained leg, when tested in hypoxia (-25 ± 8% vs. -13 ± 6%), but not in normoxia (-16 ± 15% vs. -9 ± 10%). Conclusions: Altitude training likely increases tHb, but this is not necessarily associated with improved athletic performance. IHT may induce other non-haematological adaptations; potentially an enhanced skeletal muscle oxidative capacity, but evidence for exercise capacity gains is lacking. The precise underlying causes for these adaptations require further investigation, as does any translation to athletic performance.
836

Perceptions of Leadership Styles and Job Satisfaction in a Sample of High School Athletic Directors in the United States

Turey, Colin J 01 January 2013 (has links)
The present study examined how athletic directors perceive their leadership roles in interscholastic athletics and the relationship of their leadership styles to their job satisfaction. The conceptual framework of this study was Bass and Avolio’s (1994) full range leadership model, also known as the transformational-transactional leadership model, which consists of 9 factors—5 transformational behaviors: idealized influence (attributed), idealized influence (behavior), inspirational motivation, intellectual stimulation, and individualized consideration; 2 transactional behaviors: contingent reward and management-by-exception (active); 2 passive/avoidant behaviors: management-by-exception (passive) and laissez-faire. These 9 factors are measured by the Multi-Factor Leadership Questionnaire (MLQ). The study was also informed by Chelladurai’s multidimensional model of leadership in sport which focuses on transformational effects of sport leaders on individual satisfaction and group performance. The study was significant in that the effects of transformational leadership on individuals in sporting organizations have not been fully explored in previous research. Both the MLQ and the Minnesota Satisfaction Questionnaire (MSQ) served as data collection tools. A sample of 500 athletic directors from across the United States was invited to participate in an electronic survey. Usable data were returned by 55 (11%) of the original sample. Participants self-assessed their leadership styles via the MLQ and job satisfaction via the MSQ. Data were analyzed via canonical correlation analysis followed by canonical commonality analysis. One canonical root was interpreted (Rc2 = .22; pCanonical structure coefficients indicated that Transformational and Passive/Avoidant Leadership made major contributions to the predictor canonical variate; the dependent canonical variate was defined by both Intrinsic and Extrinsic Satisfaction. Canonical commonality analysis indicated that Transformational Leadership had the largest unique variance partition; the largest common variance partition was shared by Transformational and Passive/Avoidant. The analysis also indicated two variable suppressor effects. There was a moderate correlation between athletic directors’ leadership styles and their job satisfaction; however, the directionality of the relationships of the variables in the leadership set with satisfaction was unexpected: (a) the relationship between transformational leadership and job satisfaction was found to be negative, and (b) the relationship between passive/avoidant leadership and job satisfaction was positive.
837

Atletický stadion / Athletic stadium

Prkna, Jan January 2013 (has links)
Civil two floors building serving as a base for athletes with further use for offices, cafe-bar, a fitness center and billiards club. The building is being designed in Jihlava in the area of football pitches with athletic oval. The building is situated near the cinema, children's playground and the Zoological Garden in Jihlava. Built-up land area is 2006 m2. The maximum capacity of the building is 418 persons and 430 capacity of grandstands. The building is constructed of ceramic bricks Porotherm. The roof construction is made of wooden trusses with a slope of three degrees. The draft of the object emphasizes the building layout, fire safety and energy savings.
838

Gaelská atletická asociace a Irská fotbalová asociace v kulturní paměti občanů Severního Irska / Gaelic Athletic Association and Irish Football Association in the cultural memory of the citizens of Northern Ireland

Razím, Tomáš January 2015 (has links)
The Gaelic Athletic Association (GAA) and the Irish Football Association (IFA) were founded in the 1880s and throughout the history have become more than mere sport organizations. Mainly because of the violent history of Northern Ireland during the Troubles, both associations became entrenched in the respective cultural memories of the two competing identities of Northern Ireland. The large-scale violence ended in 1998 with the signing of the Belfast Agreement that was meant to bring peace and inter-communal cooperation to the region. This paper analyses the development of the two associations after 1998 in the context of the theory of cultural memory created by Jan Assmann. It concludes that the IFA has changed profoundly since the end of the Troubles. It left its post in the unionist-protestant cultural identity and now represents part of the new Northern Irish identity which transcends the social division and is still in an early stage of development. The GAA, on the other hand, went the other way and decided to strengthen its position among nationalists and Catholics in spite of its anti-sectarian and anti-racist ethos and gestures. This difference stems mainly from different history and structure of both associations and the fear of the GAA of becoming marginalized by the British sports if it...
839

Test-Retest Reliability and Influence of Visual Constraint During Two Novel Reactive-Agility Tasks

Duncan, Samantha Lynn January 2021 (has links)
No description available.
840

Exploring the relationship between on- and off-ice interlimb asymmetries in professional men’s ice-hockey

Pearson, Aaron 08 1900 (has links)
Introduction : Les joueurs de hockey sur glace effectuent des mouvements asymétriques en utilisant la rotation du torse et des hanches lors des passes et des tirs. Les asymétries entre les segments corporels peuvent avoir un impact sur la capacité de sprints répétés, la puissance verticale lors de sauts à contre-bas et les performances sportives générales. La force isométrique de la hanche et le saut à contre-bas sont couramment évalués chez les joueurs de hockey sur glace en raison de leurs relations avec les performances en patinage et l'incidence des blessures à l'aine, respectivement. Objectif : Cette étude vise explorer si les asymétries obtenues lors des évaluations des forces isométriques de la hanche et des sauts à contre-bas sont associées à celles observées lors du patinage. Méthodes : Trente-sept joueurs professionnels de l'hockey sur glace ont effectué des évaluations hebdomadaires de force et de saut de la hanche et ont porté des centrales inertielles pendant les séances sur glace tout au long des saisons pré et compétitives. Les accélérations sont mesurées pour les deux jambes et ont été utilisées pour calculer les asymétries inter-membres, en pourcentage. Résultats : Parmi tous les paramètres mesurés, seule l'asymétrie dans le pic de la force de l’attérissage du saut à contre-bas a dépassé 10% pour toutes les positions (22,1%) et par position (21,3% - 22,6%). Les joueurs de centre et à la défense ont mené à plusieurs relations modérées à grandes entre différentes asymétries lors des évaluations hors-glace (r: -0,67 - 0,38, p <0,01). Toutes les positions ont montré des relations modérées à grandes entre la résistance à la hanche et la charge de patinage sur la glace et la force moyenne par foulée (r: -0,32 - 0,56, p <0,05). Les joueurs de centre ont montré des relations modérées entre le saut à contre-bas et des asymétries sur la glace (r: -0,31 - 0,43, p <0,01). Conclusion Cette étude a révélé qu'il existe des relations significatives entre les asymétries sur- et hors glace dans le hockey professionnel masculin. Les résultats de cette étude fournissent également aux intervenants auprès de cette population des valeurs de référence pour les asymétries sur glace et hors glace. / Introduction Ice-hockey players develop asymmetrical movement patterns by favoring rotation through the torso and hips while passing and shooting. Interlimb asymmetries have been shown to affect repeated sprint ability, vertical and horizontal countermovement jump power, and general athletic performance. Isometric hip strength and the countermovement jump are commonly assessed in ice-hockey players because of their relationships with skating performance and incidence of groin injuries, respectively. Purpose: This study explored whether asymmetries returned during isometric hip strength and countermovement jump assessments relate to those from stride-by-stride analyses. Methods: Thirty-seven professional ice-hockey players performed weekly hip strength and jump assessments and wore inertial momentum units during on-ice sessions throughout the pre- and competitive seasons. Data were either available for both limbs and were utilized to calculate inter-limb asymmetries, or as an asymmetry percentage. Results: Among all parameters measured, only the CMJ peak landing force asymmetry exceeded 10% for all positions (22.1%) and by position (21.3% - 22.6%). Centers and Defense positions returned several moderate to large relationships between fitness assessment asymmetries (r: -0.67 – 0.38, p < 0.01). All positions returned moderate to large relationships between hip strength and on-ice skating load and average force per stride (r: -0.32 – 0.56, p < 0.05). Centers returned moderate countermovement jump and on-ice asymmetries (r: -0.31 – 0.43, p < 0.01). Conclusion: This study revealed that significant relationships exist between on- and off-ice asymmetries in men’s professional ice-hockey. The results from this study also provide practitioners with reference values for on- and off-ice asymmetries.

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