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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.
411

Achilles Tendon Changes in Downhill, Level and Uphill Running

Neves, Katy Andrews 01 March 2014 (has links) (PDF)
In this study, we examined how hill running affects the Achilles tendon, which is a common location for injuries in runners. Twenty females ran for 10 min on three randomly selected grades (-6%, 0%, +6%). Achilles tendon (AT) cross-sectional area (CSA) was imaged using Doppler ultrasound and peak vertical forces were analyzed using high-speed (240 Hz) videography. A metabolic cart and gas analyzer ensured a similar metabolic cost across grades. Data were analyzed using a forward selection regression. Results showed a decrease in AT CSA from pre-run to post-run (p = .0001). Peak vertical forces were different across grades (p = .0001) with the largest occurring during downhill running and smallest during uphill running. The results suggest that the Achilles tendon is affected by running and a decrease in CSA appears to be a normal response. The AT CSA does not differ between grade conditions when metabolic cost of running is matched, suggesting an adaptive effect of the AT. Coaches and athletes can use this knowledge to develop workout protocols that transition runners to downhill running and allow them to adapt to these greater forces.
412

Health risks of distance running: modelling the predictors of running addiction, overuse injuries, and infectious illness

Struwig, Gillian Anne 02 1900 (has links)
Text in English / Regular exercise has significant physical and psychological health benefits yet, paradoxically, may also have harmful effects. The purpose of this study was to investigate the physical and psychological health risks of distance running, a popular participation sport in South Africa. Structural equation modelling was employed to examine the personality and motivational antecedents of running addiction and its influence, in turn, on self-reported overuse injuries and upper respiratory tract infections in 220 athletic club members. The predictors and physical health effects of customary training load were also assessed. It was found that perfectionistic concerns, Type A behaviour pattern, and task goal orientation had a direct, positive impact on running addiction, which predicted higher running injury scores. In contrast, training workload (Volume × Intensity) was inversely related to injury risk. Neither running addiction nor any training load variables influenced infectious illness susceptibility. The findings of this study indicate that maladaptive perfectionism, Type A behaviour, and achievement goal orientation may be risk factors for running addiction, which may, in turn, contribute to increased injury incidence in South African distance runners. Conversely, heavier training loads may be protective against injury occurrences in this population. The results of this research may help to enhance current understanding of the possible health hazards of distance running. This knowledge may have practical implications for the health and well-being of runners of diverse levels of ability and experience. / Psychology / D.Litt. et Phil. (Psychology)
413

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)
414

A resposta de andar na roda como reforço em ratos: um estudo exploratório sobre a resposta de andar na roda como reforço e sua relação com a restrição do tempo de alimento disponivel

Pedroso, Mariana Queiroz Martins 16 May 2005 (has links)
Made available in DSpace on 2016-04-29T13:18:10Z (GMT). No. of bitstreams: 1 Mariana Queiroz Martins Pedroso.pdf: 1093596 bytes, checksum: 07eb393466b02df8274ee63254b1d002 (MD5) Previous issue date: 2005-05-16 / Replicating Iversen s (1993) procedure, this study s goal was to increase the comprehension of the running response of rats on an activity wheel when running was a consequence of responding on a fixed-ratio schedule. The study also explored the impact of a restricted period of food availability on the reinforcing value of wheel running. Body weight, food and water consumption of six female rats were systematically measured. Five subjects were also submitted to a procedure designed to install wheel-running as a consequence for lever pressing. After baseline measures of wheel running, a gradual restriction of the session time when wheel-running was possible was implemented, followed by the shaping of a lever pressing response reinforced by wheel-running, and a phase when lever pressing was maintained by intermittent reinforcement on a FR. The FR values initially were increased automatically and later the FR values were increased based on the analysis of the subject s responses. One subject was finally submitted to an extinction procedure of the lever pressing response. The availability of food also varied during experimental phases concomitantly with the manipulation of lever pressing and wheel running: food was initially available all the time, later food was available for 90 minutes daily, and, finally, it was available all the time again for some subjects.. Results indicated that the lever pressing that produced wheel running as a consequence was acquired and maintained for 4 of 5 subjects. Nevertheless these responses were emitted at low rates, and were acquired only after a long training. For one subject, the lever pressing response was acquired only when food was its consequence and was, then maintained when the consequence became wheel-running. Results also showed that rate of lever pressing and the number of wheel turns decreased as the value of fixed ratio increased, and that weight loss did not depend on the number of wheel turns, but seemed to depend on the time restriction of food availability. It is discussed that for 3 subjects the time restriction of food availability was an establishing operation for wheel-running / Similar ao procedimento de Iversen (1993), este estudo buscou compreender o funcionamento da resposta de andar na roda como reforço, em esquema de reforçamento em FR e explorou o impacto da restrição do tempo de alimento disponível sobre o valor reforçador de andar na roda. Seis ratas foram submetidas à linha de base de peso corporal, consumo de alimento e água. Destas, cinco foram designadas às seguintes fases tendo a possibilidade de andar na roda: sessões de linha de base, redução gradual do tempo de possibilidade de andar na roda; modelagem da resposta de pressão à barra; reforçamento intermitente em FR com aumento automático do valor da FR, aumento do valor da FR determinado pela análise das respostas emitidas pelos sujeitos e extinção da resposta de pressão à barra. Sobre o alimento, destacam-se as seguintes condições: alimento disponível por tempo integral, 90 de alimento disponível por dia e alimento por tempo integral. Tais condições acompanharam as manipulações das variáveis relativas a andar na roda. Os resultados apontaram que quatro de cinco sujeitos adquiriram com muito treino e mantiveram com taxas baixas a resposta de pressão à barra tendo a possibilidade de andar na roda como conseqüência, diferente do obtido por Iversen (1993). Para um sujeito, inclusive a resposta de pressão à barra só foi instalada usando alimento como reforço, e depois mantida com a resposta de andar na roda. Observou-se também que as taxas de respostas de pressão à barra e o número de voltas na roda diminuíram com o aumento do valor da FR, e que a perda de peso dos sujeitos não dependeu da quantidade de voltas na roda e sim da restrição do tempo de alimento disponível. Pode-se dizer que a restrição do tempo de alimento foi uma operação estabelecedora que alterou a efetividade reforçadora do andar na roda para quatro dos sujeitos
415

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)
416

Gestion de l'impact et de la fatigue neuromusculaire en trail running / Impact and neuromuscular fatigue in trail running

Giandolini, Marlène 10 November 2015 (has links)
Bien que constitué anatomiquement et physiologiquement pour la course d’endurance, l’Homme est considérablement exposés à diverses blessures musculo-squelettiques liées à la répétition de contraintes mécaniques. Le coureur de trail running par exemple est soumis à de nombreux impacts ainsi qu’à une fatigue et des dommages musculaires sévères. Ces chocs répétitifs et dommages musculaires réduiraient la tolérance du coureur face aux contraintes mécaniques le poussant ainsi à altérer sa cinématique de course. Par conséquent, minimiser les dommages musculo-squelettiques serait déterminant pour la performance en trail running. Des évidences montrent que la pose de pied altère la localisation et l’intensité des contraintes appliquées au système musculo-squelettique. L’objectif de ce travail de thèse a été d’étudier l’influence du pattern de pose de pied sur l’impact et la fatigue neuromusculaire en trail running. Les phases de descente ont été tout particulièrement étudiées du fait qu’elles sont les plus traumatisantes. En effet, ce travail de thèse a mis en évidence qu’en situation de trail running, l’intensité de l’impact augmente lorsque la pente diminue, et que la fatigue neuromusculaire périphérique est aussi sévère à la suite d’une descente isolée qu’après un ultra-trail de plusieurs heures. En étudiant l’influence de la pose de pied adoptée au cours d’une descente en situation de trail running, il a été observé qu’attaquer le sol par l’avant du pied augmentait la fatigue neuromusculaire aux extenseurs du genou. Cependant, une importante variabilité dans les patterns de pose de pied adoptés au cours de la descente a été associée à une baisse de la fatigue neuromusculaire aux extenseurs du genou et fléchisseurs plantaires. L’influence de la pose de pied sur l’intensité du choc et le contenu vibratoire le long des axes axial et transversal a également été démontrée : adopter une attaque talon diminue la sévérité du choc axial mais réduit l’intensité du choc transversal. La principale conclusion est qu’aucun pattern de course ne saurait être universellement recommandé du fait que « changer de pose de pied » est synonyme de « changer la localisation et la magnitude des contraintes appliquées au système musculo-squelettique ». En ce sens, alterner entre différents patterns de course serait une stratégie efficiente en trail running / Although Humans are “born” anatomically and physiologically adapted to long distances run, they are substantially exposed to various musculoskeletal overuse injuries. Trail runners sustain a high number of foot-to-ground contacts and develop severe muscle fatigue and damages. Repetitive shocks and muscle damages would reduce the runners’ tolerance to mechanical strains leading to changes in running kinematics. Minimizing musculoskeletal damages is therefore considered paramount for performance in trail running. Numerous studies highlighted that the foot strike pattern alters the localization and magnitude of the mechanical strains applied on the musculoskeletal system. The main purpose of this thesis was to study the influence of the foot strike pattern on impact and neuromuscular fatigue in trail running. Downhill sections were mainly investigated since they are the most mechanically stressful. Indeed, it was observed from this thesis’ work that, in real trail running practice, the impact intensity increases as the slope decreases, and that the neuromuscular fatigue induced by a single downhill run is as severe as the one induced by an ultratrail race that lasts several hours. Investigating the effect of the foot strike pattern adopted during a downhill trail run on fatigue, it was observed that forefoot striking increases the neuromuscular fatigue at knee extensors. However, a high variability in foot strike patterns adopted was associated to a lower neuromuscular fatigue at both knee extensors and plantar flexors. The effect of the foot strike pattern on axial and transversal shock and vibration content was also demonstrated: heel striking was correlated to a lower impact severity along the axial axis of the skeleton but a greater one along its transversal axis. The main conclusion of this thesis is that no single foot strike pattern should be universally advised due to “changing of foot strike” means “changing the localization and magnitude of the mechanical stress applied on the musculoskeletal system”. Switching between different running patterns might be an efficient strategy in trail running
417

Personlighet hos ultralöpare och cyklister : En jämförande studie av the Big Five hos deltagare i Ultravasan och Cykelvasan 2015 / Personality in ultra runners and cyclists : A comparative study of the Big Five among participants in Ultravasan and Cykelvasan

Bröms, Emelie, Hultenmo, Andreas January 2016 (has links)
Allt fler människor deltar i lopp som sträcker sig över långa distanser. Denna studies syftevar att undersöka om dessa människors personligheter skiljer sig åt beroende på vilkengren de deltar i, och i så fall på vilket sätt. Med utgångspunkt i femfaktorteorin (Big Five)och med hjälp av ett självskattningsformulär, Revised NEO Personality Inventory, undersöktesoch jämfördes 214 löpare i Ultravasan 2015 och 145 cyklister i Cykelvasan 2015.Frågeställningen som föranledde arbetet var ifall löparnas personlighet skiljer sig från cyklisternas.Resultaten visade att löpare har en högre grad öppenhet i jämförelse med cyklisterna.Löparna hade även en lägre grad av extraversion i förhållande till cyklisterna,en skillnad som var statistiskt signifikant. Generellt sett visade resultaten små skillnadermellan löpare och cyklister. / More people than ever participate in long distance races and the purpose of this study wasto investigate the personality of these individuals. We had 214 Ultravasan runners and145 Cykelvasan cyclists complete the Revised NEO Personality Inventory test, to assesstheir personality based on the Big Five. The main question was whether the personality ofthe runners would differ from the cyclists’.Results showed that runners scored higher on openness compared to the cyclists.Furthermore, runners were significantly less extrovert than the cyclists. Generally however,the results showed minor differences in personality between the two groups.
418

An injury profile and management analysis of marathon runners at selected marathons in the great eThekwini and uMgungundlovu Municipalities during 2014

Van Niekerk, Giselle January 2016 (has links)
Submitted in partial compliance with the requirements for the Master’s Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2016. / Background: Running injuries are increasingly common as participation in this sport increases. Health care providers need to be better able to treat and manage these injuries and prevent their recurrence. Thus, there is a need for profiles of different population groups to enable the development of health promotion and injury prevention strategies. This research study profiled and tracked runners over seven marathons held in the eThekwini and uMgungundlovu Municipalities during the first quarter of 2014. Methods: This Durban University of Technology, Institutional Research and Ethics Committee approved retrospective Chiropractic Treatment Facility record analysis, analysed 741 recorded marathon visits. The records were based on a previously validated data collection tool (CSSA questionnaire) that allowed clinical data to be captured relating to patient demographics, anatomical site of the complaint, clinical impression, diagnosis and treatment. These fields were analysed for each visit, and then captured in SPSS version 22 with records only being excluded because they were unsigned. Descriptive and inferential statistics (McNemar’s tests) were compiled and a p-value of 0.05 was used. Results: The majority of the runners were Black males of approximately 40 years of age. A total of 95.6% of runners presented with overuse injuries, of which 73.6% and 89.3% had no history of previous injury or trauma respectively, and with 94.7% being able to continue participation. The shin and calf (21.7%), thigh (21.6%) and lumbar regions (16.1%) were most commonly affected by injuries which were predominantly muscle strains (23.2%) and SI syndrome (21.4%). These injuries were treated by manipulation (82.8%), massage (57.2%) and PNF stretching (33.6%). With runners that presented at subsequent marathons, a significant difference (McNemar’s p=0.013) in history of previous injury between the first and second marathon was found, with the runner being more likely to report a history of previous injury at their second marathon visit. Specific trends, although not significant, were found for specific subgroups (defined by age, gender, ethnicity, history of previous injury / trauma and chronicity of the diagnoses). Conclusion: The data is not dissimilar to the literature on running injuries, although specific trends in terms of sub categories were noted. These trends require further investigation through prospective, longitudinal studies. / M
419

\"Papel da atividade física espontânea no comportamento e na neurotransmissão em áreas do circuito mesocorticolímbico de reforço e do hipocampo em ratos durante a administração crônica de nicotina\" / Role of the spontaneous wheel running on behavior and neurotransmission in areas of the mesocorticolimbic circuit and hippocampus of rats during chroni treatment of nicotine

Betz, Andreas 31 October 2006 (has links)
Resumo A nicotina é um alcalóide encontrado em cigarros de tabaco sendo um dos maiores responsáveis pelo vício e por problemas associados ao tabagismo. Com relação ao vício, que é um fenômeno comportamental complexo, ressaltamos a ação da nicotina como um potente agente viciante que altera não só mecanismos celulares como também comportamentais e de aprendizagem. O trabalho para a reversão do vício a drogas como a nicotina é bastante difícil de modo que intervenções alternativas, como o exercício físico, são práticas que têm estado cada vez mais em evidência. Após tratarmos cronicamente ou não ratos com nicotina durante 60 dias e submetê-los ou não a atividade física espontânea por 7 semanas, verificamos que nem o tratamento crônico com a droga e nem a atividade física alteraram parâmetros como o peso e a pressão arterial média dos ratos bem como a marcação para o RNAm da enzima tirosina hidroxilase na Área Tegmental Ventral e da glutaminase no Córtex Pré-Frontal. Porém, verificamos alterações na frequência cardíaca e na ansiedade dos ratos, além do RNAm da glutaminase e do fator neurotrófico derivado do cérebro em áreas hipocampais, sugerindo que ambos o treinamento físico espontâneo e o tratamento crônico com nicotina podem alterar o comportamento, a ansiedade e a memória dos ratos utilizados. / Resumo A nicotina é um alcalóide encontrado em cigarros de tabaco sendo um dos maiores responsáveis pelo vício e por problemas associados ao tabagismo. Com relação ao vício, que é um fenômeno comportamental complexo, ressaltamos a ação da nicotina como um potente agente viciante que altera não só mecanismos celulares como também comportamentais e de aprendizagem. O trabalho para a reversão do vício a drogas como a nicotina é bastante difícil de modo que intervenções alternativas, como o exercício físico, são práticas que têm estado cada vez mais em evidência. Após tratarmos cronicamente ou não ratos com nicotina durante 60 dias e submetê-los ou não a atividade física espontânea por 7 semanas, verificamos que nem o tratamento crônico com a droga e nem a atividade física alteraram parâmetros como o peso e a pressão arterial média dos ratos bem como a marcação para o RNAm da enzima tirosina hidroxilase na Área Tegmental Ventral e da glutaminase no Córtex Pré-Frontal. Porém, verificamos alterações na frequência cardíaca e na ansiedade dos ratos, além do RNAm da glutaminase e do fator neurotrófico derivado do cérebro em áreas hipocampais, sugerindo que ambos o treinamento físico espontâneo e o tratamento crônico com nicotina podem alterar o comportamento, a ansiedade e a memória dos ratos utilizados.
420

Gestion des modifications podales et des pressions plantaires en ultra-trail par des semelles orthopédiques équipées de barres rétro-capitales métatarsiennes / Management of foot modification and plantar pressure modifications in ultra-trail by foot orthoses equipped with retro-capital bars

Vermand, Stéphane 15 May 2019 (has links)
La course d'ultra-trail en montagne provoque de nombreuses altérations d'ordre biomécaniques, physiologiques, neuro-musculaires, posturales et psychologiques qui peuvent engendrer certaines blessures. Cependant, assez peu d'études se sont intéressées aux modifications que peuvent subir les pieds. C'est dans ce cadre que nous avons réalisé 3 études. La première effectuée auprès de 10 coureurs a montré que les avants-pieds s'élargissent et la pression plantaire sous l'avant-pied augmente à partir de la mi-distance d'une épreuve d'ultra-trail de 170 km (UTMB®). La surpression sous l'avant-pied qui est due au déplacement vers l'avant du centre de pression, est susceptible d'accroitre le risque de fracture de fatigue des métatarses. Ces modifications qui ont été observées jusqu'à la fin de la compétition sont probablement liées à la fatigue des sujets. Pour contrecarrer ces modifications, nous avons proposé d'utiliser des semelles orthopédiques moulées comportant chacune une barre rétro capitale (BRC) placée en arrière des têtes métatarsiennes. La 2ème étude réalisée chez 48 coureurs a montré que cet élément orthopédique permet lors du maintien de la posture debout de diminuer les pressions plantaires sous les avants-pieds, de reculer le centre de pression, mais aussi les centres articulaires de la hanche, des épaules et de la tête. La 3ème étude avait pour objectif d'évaluer chez 10 coureurs à pieds l'effet immédiat, à court terme (après 4 semaines) et moyen terme (après 12 semaines) du port des semelles BRC sur la répartition des pressions plantaires et la cinématique articulaire. Un groupe contrôle de taille égale a utilisé pendant la même période des semelles moulées qui ne comportaient aucun élément orthopédique. Cette étude longitudinale a montré que les pressions plantaires sous les têtes métatarsiennes étaient réduites immédiatement avec le port des semelles BRC. Après 4 semaines, cette réduction s'accentuait et l'angle de flexion de la cheville était augmenté lors de l'appui. Après 12 semaines, l'extension maximale du genou était augmentée et la plupart de ces modifications étaient aussi observées même si les sujets utilisent des semelles plates. Aucune variable n'a été modifiée chez les sujets du groupe contrôle. En ce qui concerne les applications pratiques de ces travaux de thèse, au regard de nos résultats, nous pouvons conseiller aux coureurs de longue distance soufrant de douleur au niveau de l'avant-pied de choisir des chaussures un peu plus larges et, d'utiliser des semelles orthopédiques BRC pour réduire la pression sous l'avant-pied. / Mountain Ultra Marathon is causing many biomechanical, physiological, neuromuscular, postural and psychological alterations which can lead to certain injuries. However, there are few studies has been focused on the feet. In this context, we conducted three original studies. The first one, performed with 10 runners has shown that the front feet width and the plantar pressure under the forefoot has increased from the mid-distance of a 170km ultra-trail race (UTMB®). The overpressure under the forefoot is due to the forward displacement of the center of pressure which may increase the risk of stress fracture of the metatarsals. These changes that were observed until the end of the competition are probably related to the increase of muscular fatigue of the subjects. In opposition of these changes, we proposed to use moulded orthopaedic insoles that comprising a metatarsal retro-capital bar (MRCB) placed behind the metatarsal heads. The second study carried out in 48 runners has shown that this MRCB element allows to reduce the plantar pressures under the front feet during the standing support by moving backward the center of pressure, and also the hip, the shoulders and the head. The objective of the third study was to evaluate the immediate, short-term (after 4 weeks) and medium-term (after 12 weeks) effect of wearing MRCB insoles on plantar pressure distribution and joint kinematics during running with 10 runners. A similar control group of equal size used during the same period of training moulded insoles without orthopaedic element. This longitudinal study showed that the plantar pressures under the metatarsal heads were reduced immediately with wearing MRCB soles. After 4 weeks, this reduction was accentuated and the ankle's angle of flexion was increased during the stride support. After 12 weeks, the maximum knee extension was increased and most of these changes described aboved were also observed even if the subjects used flat insoles. Any significant changes have been observed in the control group whatever the test period. Regard to these results, we can advise long-distance runners that suffer of pain in the forefoot region to choose slightly larger shoes and to use MRCB orthopaedic insoles to reduce pressure under the forefoot.

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