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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.
61

Differences in energy and nutrient intakes, body composition, and body image between adolescent male and female athletes (swimmers) and non- athletes

Shunk, Sally A. January 1993 (has links)
Competitive swimming is a sport in which "the need to succeed" is stressed and the desire to reach the optimal level of performance--physically, emotionally, and nutritionally is strong. This research sought to investigate whether there were differences in nutrient intakes, percent body fat, and body image between male and female swimmers and their non-athletic counterparts at Muncie Central High School in Muncie, Indiana.The accessible population for this study included those male and female athletes and non-athletes, ages 14 to 18, who attended Muncie Central High School during the 1989-1990 school year.The data indicated that athletes did not differ from non-athletes while males and females did differ significantly in significant differences in height between athletes and non-athletes, primarily due to the differences in the height of female athletes as males appeared to be similar, but female athletes were one-half inch taller, on the average, than female non-athletes. There were no significant differences between the weights of male between athletes and non-athletes,male non-athletes were and female athletes and non-athletes; however, male athletes were 13 lbs. lighter, on the average, than their male counterparts. There was a significant interaction, in percent body fat, significantly fatter than male athletes. There was a tendency for males to have lower scores on the Eating Attitudes Test (EAT) than females, suggesting that males were at lower risks for disorders than females.These data suggest that nutrition education programs should be planned to ensure good diets for all students, athletes, and non-athletes. / Department of Home Economics
62

A profile of musculoskeletal injuries in competitive swimmers in the greater Durban area

Sutherland, Kelly Michelle January 2008 (has links)
Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Chiropractic, Durban Institute of Technology, 2008. / lntroduction: Swimming is one of the most popular participation sports 1 as people are drawn to swimming for leisure, cardiovascular workouts, or competition 2 . As a result, the sport of swirnrninq has improved 9reatly over the past 20 years 3 . Olbjectoves: The aim of this study was to determine a profile of musculoskeletal injuries in competitive swimmers in the greater Durban area of KwaZulu-Natal, South Africa; as well as to determine whether any relationships exist between swimming injuries sustained in this study and the risk factors identified in other studies, and to compare the results with international data. Therefore; for the purpose of this study, the following information was gathered in order to build up an injury profile: o Demographics of competitive swimmers in South Africa, o The participants swimming history, o The presence of any past or current injuries and o Factors associated with current and previous injuries were also investigated. This study was a prospective, cross-sectional, questionnaire based study, investigating the profile of musculoskeletal injuries in 101 competitive swimmers in the greater Durban area. The data was collected by means of a self-administrated questionnaire, which was completed by the participants, under the supervision of the researcher, parents or coach. / M
63

The Effects of Self-Recording and Projected Levels of Aspiration Upon Competitive Swimming Performance

Hamlett, Laurie Ray 08 1900 (has links)
The purposes of the study were to determine the effects of self-recording techniques upon competitive swimming times, to determine the relationship between stated level of aspiration and subsequent performance, and to determine the influence of success or failure upon stated levels of aspiration. Subjects were fifteen female high-school competitive swimmers. Five subjects utilized self-recording techniques and projected levels of aspiration; ten subjects did not. Data were analyzed by analysis of covariance and by regression analysis. Alpha was .05. Conclusions of this study were that self-recording techniques do not significantly affect competitive swimming times, that a strong relationship exists between stated level of aspiration and subsequent performance, and that successful and unsuccessful performances generate increases in stated levels of aspiration.
64

Vývoj výkonnosti evropských juniorských medailistů z let 2000-2008 v plavání / Evolution of the perfomance of European junior medalists from the years 2000-2008 in swimming

Kopalová, Michaela January 2015 (has links)
Title: Evolution of the performance of European junior medalists from the years 2000 - 2008 in swimming Objective: The aim of the Thesis is to find out whether swimmers who won a medal at the European Junior Championship in the period 2000-2008 continue swimming careers for the next five years. Methods: We chose the method of data analysis to describe the process of swimming careers. Data were obtained from scorecards of the European Junior Championships 2000 - 2008, European Championship in short pool 2001-2013 and the Olympic Games 2004, 2008, 2012. Results: Our survey shows that 70% of swimmers after their medal success at the European Junior Championship in 2000-2008 managed to qualify for the upcoming European Championship in the period. Analysis of collected data shows that 25% of competitors achieved medals at the European Championships in the years 2001-2013. Based on our research we can deduce that the most of the medalist from the European Junior Championship do not continue swimming careers in their adulthood. Keywords: Junior age, swimming career, swimming performance, swimming disciplines
65

Locomotion et écoulement dans les fluides complexes confinés / Locomotion and Flow in complex and confined fluids

Jibuti, Levan 21 October 2011 (has links)
Cette thèse est consacrée à l'étude de la dynamique et de la rhéologie des fluides complexes. Nous utilisons une méthode de simulation numérique à trois dimensions. Les systèmes que nous étudions ici sont des suspensions de micro-nageurs actifs, des suspensions de particules sphériques rigides en présence d'un champ externe auquel elles sont sensibles et de la dynamique de suspensions de particules sphériques et confinées en cisaillement. Les Micro-nageurs sont les objets microscopiques qui se propulsent dans un fluide et ils sont omniprésents dans la nature. Un exemple commun de micro-nageurs est la micro-algue textit{Chlamydomonas} . Un des buts principaux de cette thèse est de comprendre l'effet de la motilité de ces micro-organismes sur les propriétés macroscopiques globales de la suspension, telles que la viscosité effective pour expliquer les observations expérimentales. Nous avons élaboré différents modèles de suspensions de textit{Chlamydomonas} et effectué des simulations numériques utilisant la version 3D de la dynamique des particules fluides (FPD) (méthode expliquée dans cette thèse). Les résultats de nos simulations numériques ont été présentés et discutés à la lumière des observations expérimentales. Un des modèles proposés intègre tous les phénomènes observés expérimentalement et sont applicables à d'autres types de suspensions de micro-nageurs. Cette thèse consacre également un chapitre sur les effets du confinement sur la dynamique de cisaillement des suspensions diluées de particules sphériques. Nous avons constaté que dans la géométrie confinée, la vitesse angulaire des particules diminue par rapport à celle imposée par l'écoulement de cisaillement. La vitesse angulaire des particules diminue également lorsque la particule est proche d'une paroi unique et la vitesse de translation de la particule par rapport à la vitesse de la paroi diminue. Un autre objectif de cette thèse est d'étudier les suspensions à viscosité effective ajustable. Nous avons mené une étude numérique sur des suspensions de particules sphériques en présence d'un couple externe. Nous avons montré que le changement de vitesse angulaire des particules due à l'application d'un couple externe est suffisante pour modifier fortement la viscosité de la suspension. Basée sur des simulations numériques, une formule semi-empirique a été proposée pour la viscosité des suspensions de particules sphériques valables jusqu'à 40% de concentration. Nous avons également montré que la 2ème loi de Faxén peut être étendue par une expression empirique pour de grandes concentrations. / This work is dedicated to the study of dynamics and rheology of the complex fluids. We use three dimensional numerical simulations. The systems we study here are: suspensions of biological active micro-swimmers, suspensions of rigid spherical particles in presence of an external field and the dynamics of sheared confined spherical particles. Micro-swimmers are the microscopic objects that propel themselves through a fluid and they are ubiquitous in nature. A common example of micro-swimmers is the textit{Chlamydomonas} . One of the main goal of this thesis is to understand the effect of self-motility of these micro-organisms on the global macroscopic properties of the fluid, such as the effective viscosity to explain experimental observations. We elaborated different models for textit{Chlamydomonas} suspensions and conducted numerical simulations using the 3D version of the Fluid Particle Dynamics method (explained in this thesis). The results of our numerical simulations has been shown and discussed in light of the experimental observations. One of the proposed models incorporates all experimentally observed phenomena and is expendable for other types of micro-swimmer suspensions. This thesis is also dealing with the effects of confinement on the dynamics of sheared spherical particles. We found that in confined geometry, angular velocity of sheared particles decreases compared to the one imposed by the shear flow. The angular velocity of the particles decreases also when the particle are close to a single wall and the translational velocity of the particles changes so that the difference between velocity of the particle and the velocity of the wall decreases. Another objective of this work is to study suspensions with tunable effective viscosity. We conducted a numerical investigation of sheared spherical particle suspensions in presence of an external torque. We showed that the change of particle angular velocity with an external torque is sufficient to strongly change the effective viscosity of the suspension. Based on numerical simulations, a semi-empirical formula has been proposed for the effective viscosity of spherical particles suspensions valid up to 40% concentration. We also showed that a modified second Faxén law can be equivalently established for large concentrations.
66

Desempenho de jovens nadadores na distância de 100 metros nado crawl / Performance of young swimmers in 100 meters front crawl

Vitor, Fabrício de Mello 03 September 2008 (has links)
O presente estudo teve como objetivos descrever aspectos antropométricos, de aptidão física específica e, técnicos de nado; verificar as relações existentes entre idade cronológica, antropometria, aptidão física específica e técnica de nado com o desempenho na distância de 100 metros nado Crawl e verificar a influência das variáveis antropométricas, de aptidão física específica e, técnicas de nado sobre o desempenho de jovens nadadores na distância de 100 metros Nado Crawl. Participaram do estudo 24 nadadores púberes do sexo masculino com idade de 13,0 ± 0,7 anos. A análise de regressão múltipla (método forward) foi realizada com o propósito de explicar a variabilidade da velocidade obtida nos 100 metros Nado Crawl. Velocidade média da potência anaeróbia (r² = 0,67), índice de eficiência de nado (r² = 0,62) e velocidade crítica (r² = 0,34) explicaram em 88% a variabilidade da velocidade obtida nos 100 metros nado Crawl. O modelo de regressão estatístico foi significante ao nível de 0,05 e o erro padrão de estimativa foi de 0,03. O custo energético da prova de 100 metros Nado Crawl tem papel relevante no maior peso preditivo da potência anaeróbia assim como, a inclusão da velocidade crítica (resistência aeróbia) no modelo de regressão. Quanto ao índice de eficiência de nado, é possível assegurar que, a aplicação efetiva da força contra a água é o fator determinante da economia de movimento nesta atividade, ou seja, quanto melhor a técnica de nado, menos energia será gasta e melhor será o desempenho final / The purposes of this study were to describe: anthropometric aspects, specific physical fitness and stroking parameters; to verify relationship between anthropometric, specific physical fitness, stroking parameters and 100 meters front Crawl and to verify influence of anthropometry, specific physical fitness and stroking parameters variables over performance in 100 meters front Crawl in young swimmers. The group was composed by 24 pubertal males with 13,0 ± 0,7 years-old. Multiple regression analysis (forward method) was used to explain variance of 100 meters front Crawl velocity. Anaerobic power velocity (r² = 0,67), swimming efficiency index (r² = 0,62) and critical velocity (r² = 0,34) explained 88% of variance 100 meters front Crawl in young male pubertal swimmers. Regression model was significantly at 0,05 level and, estimative error standard was 0,03. Energetic expenditure of 100 meters front crawl has a relevant importance in predictive value of anaerobic power and inclusion of critical velocity on regression. About swimming efficiency index, effectiveness of force against water is main reason for swimming economy and, as better swimming technique, less energy will be expended resulting in better performance
67

Efeitos do ácido ascórbico em biomarcadores de estresse oxidativo em nadadores de alto rendimento de Ribeirão Preto/SP / Effects of ascorbic acid on oxidative stress biomarkers in high-performance swimmers of Ribeirão Preto/SP

Picchi, Monike Garlipp 06 October 2010 (has links)
O exercício físico intenso altera o sistema antioxidante, aumentando a geração de radicais livres e/ou diminuindo a concentração de antioxidantes. Assim o objetivo deste estudo foi verificar os efeitos da oferta de vitamina C através de um suplemento alimentar e dieta rica em ácido ascórbico no estresse oxidativo induzido pelo exercício. A amostra foi composta por 13 nadadores de elite (6 homens e 7 mulheres), com idades entre 18 e 26 anos, IMC médio 21,8kg/m², que treinavam em média 19,4h semanais. Os atletas foram submetidos à carga de exercício aguda em 3 fases, controle (C), dieta rica em vitamina C (D) e suplemento de vitamina C (S), nas quais amostras de sangue foram colhidas antes, imediatamente após e 24 horas depois do exercício, para determinação bioquímica e do estresse oxidativo. O uso de suplementos alimentares foi feito pela maioria dos nadadores (92,3%), e os suplementos mais usados eram Maltodextrina, associação de proteína e carboidrato, enquanto o relato do consumo de antioxidantes não foi muito freqüente (25%). Em relação ao consumo de antioxidantes, os nadadores apresentavam consumo alimentar variável de vitamina C, sendo que muitos deles apenas adequaram o consumo devido à adição feita pelo estudo. O consumo de vitamina E foi inadequado para todos os atletas, já o consumo de selênio, retinol e zinco tiveram uma grande oscilação. Durante as fases o único antioxidante que apresentou flutuações foi o ácido ascórbico, que foi menor na fase C em relação às outras fases. Para a maioria dos indivíduos o consumo de carboidrato e fibras se mostrou insuficiente, e o de lipídeos e calorias adequados, enquanto o consumo de proteínas variou bastante. O uso de dieta rica em vitamina C favoreceu uma menor peroxidação lipídica em nadadores de alto rendimento, já que apresentou menores valores de FOX, e diminuição da peroxidação lipídica após exercício, pela diminuição dos valores de TBARS, enquanto tiveram aumento dos níveis de vitamina C no plasma logo após o exercício. Enquanto o uso de suplemento de vitamina C, que também conteve a peroxidação lipídica após exercício, aumentou o poder antioxidante nos mesmos nadadores, devido maiores níveis do antioxidante GSH. Os quais sem uso de nenhuma adição de vitamina C tiveram um maior dano hepático e tecidual, pois apresentaram maiores níveis de TGO, menores níveis de antioxidantes, devido aos baixos níveis de vitamina C e GSH, e um aumento do ácido úrico, um antioxidante que aumenta em situações onde há grande quantidade de radicais livres presentes. Ainda pode-se verificar que, antes do exercício, quanto mais ácido ascórbico na dieta mais vitamina C, menos TGO e menos ácido úrico no sangue; e ainda logo após o exercício e 24 horas depois quanto mais ácido ascórbico menos TGO e menos ácido úrico séricos. Sendo assim as mudanças observadas com a adição de vitamina C à dieta de nadadores de alto rendimento sugere um importante papel do ácido ascórbico plasmático e da suplementação alimentar na defesa contra o estresse oxidativo induzido pelo exercício / The strenuous exercise alters the antioxidant system by increasing the generation of free radicals and / or decreasing the concentration of antioxidants. Then the aim of this study was to investigate the effects of supply of vitamin C through a dietary supplement and diet rich in ascorbic acid in the exercise-induced oxidative stress. The sample was compound of 13 elite swimmers (6 men and 7 women) aged between 18 and 26 years, average BMI 21.8 kg / m², who trained on average 19.4 hours per week. The athletes were submitted to acute exercise load in three phases: control (C), diet rich in vitamin C (D) and supplement vitamin C (S), in which blood samples were collected before, immediately after and 24 hours after exercise to biochemical determination and oxidative stress. The use of dietary supplements is done by most of the swimmers (92.3%), and supplements most used were maltodextrin, association of protein and carbohydrate, while the report of consumption of antioxidants was not very frequent (25%). Regarding the consumption of antioxidants, the swimmers had dietary vitamin C variable, and many of them just adjusted consumption due to addition made by the study. The consumption of vitamin E was inadequate for all athletes, while the consumption of selenium, retinol and zinc had a great oscillation. During the phases the only antioxidant that showed fluctuations was ascorbic acid, which was lower in phases C when compared to other phases. For most individuals the consumption of carbohydrates and fibers were insufficient, and lipid and calories adequate, while protein intake varied widely. The use of diet rich in vitamin C favored a lower lipid peroxidation in swimmers high performance, then showed lower values of FOX, and decreased lipid peroxidation after exercise by the decrease in TBARS values, while they had increased levels of vitamin C plasma immediately after exercise. While the use of supplement vitamin C, which also contained the lipid peroxidation after exercise, increased the antioxidant power of the same swimmers, due higher levels of the antioxidant GSH. This without use addition of vitamin C had a greater damage liver and tissue, because they showed higher levels of TGO, lower levels of antioxidants, due lower levels of vitamin C and GSH, and increased uric acid, an antioxidant that increases in situations where there are lots amount the free radicals presents. Further can be seen that, before exercise, the more ascorbic acid in vitamin C diet, less TGO and less uric acid in blood, and even after exercise and 24 hours after the more ascorbic acid less serum TGO and uric acid. Thus the observed change with the addition of vitamin C to the diet of high-performance swimmers suggests an important role of ascorbic acid and dietary supplementation in protecting against exercise-induced oxidative stress.
68

The Interaction between Toroidal Swimmers in Stokes Flow

January 2014 (has links)
he focus of this research has been devoted to study the interaction between two or more self-propelled toroidal swimmers in Stokes flow by applying the method of regularized Stokeslets and also study the effect of a nearby wall to the movement of a helical ring by using the method of regurlarized Stokeslets with images. In the study of the interaction between two or more toroidal swimmers, we interpret these as three-dimensional, zero Reynolds number analogues of finite vortex dipoles in an ideal fluid. Then, we examine the stability of relative equilibria that can form for these swimmers when they are initially placed in tandem or abreast. In addition, we examine the dynamics of the torus when a spherical cell body is placed at its center. This gives us an insight into the mechanical role of the transverse flagellum of dinoflagellates. Moreover, we show that the torus with a sphere moves more efficiently than one without. Lastly, we model the transverse flagellum of a dinoflagellate as a helical ring and study the effect of a nearby wall on its movement. The numerical results show that the wall baffles the movement of the helical ring, which is consistent with the phenomenon of sperm accumulation near surfaces. / acase@tulane.edu
69

Simma med huvudet : En studie kring simmares visualiseringsförmåga och användning

Runeke, Josephine January 2015 (has links)
Syftet med studien var att undersöka vid vilken situation som simmare använder visualisering mest och varför samt simmarnas visualiseringsförmåga. I studien deltog 278 simmare (15-30 år) i den kvantitativa delen och 3 simmare (17-23 år) i den kvalitativa delen av studien. De instrument som tillämpades till den kvantitativa delen var en konstruktion av SIAM och IPIES som tillsammans mäter idrottares visualiseringsförmåga och användning. Till den kvalitativa delen användes en semikonstruerad intervjumall. Resultaten från studien visade att det fanns några statistisk signifikant skillnad mellan högpresterade och lågpresterande simmare i visualiseringsförmåga. Resultaten visade att simmarena använder visualiseringen för att tänka positiv och fokusera samt förberedda sig inför nästa tävling. Dessutom sågs en tendens från den kvalitativa studien att högpresterade simmare hade bättre visualiseringsförmåga än lågpresterade och de använde visualiserings för att minska nervositet samt förbättra en prestation. Rekommendation med studien var att introducera och uppmuntra simmare att redan i lägre åldrar för visualisering som ett kompletterande träningsform till simningen, för att på så sätt förbättra simmares förberedelser inför tävling samt motivera till högre prestationsnivåer. / The aim of the study was to investigate at which situation swimmers use imagery the most, why, and the swimmers imagery ability. The study involved 278 swimmers (15-30 years) in the quantitative study, and 3 swimmers (17-23 years) in the qualitative part of the study. The instruments that were applied to the quantitative part were a construction of SIAM and IPIES which together measure the athlete's imagery ability´s and uses. For the qualitative part, a semi constructed interview was applied. The result of the study showed that there were statistically significant differences between high-performance and low-performance swimmers in imagery ability. The results showed that the use imagery to think positive and focused and prepare themselves before the next race. There was also a tendency from the qualitative study that high-performance swimmers had better imagery ability than lowperformance and used imagery to reduce nervousness and to improve the performance. Recommendation from the study was to introduce and encourage swimmers in lower ages to imagery as a complementary exercise for swimming, to improve the swimmer's preparation for the competition and motivate to higher performance levels
70

Disordered eating : effects on athletic performance

Lamparski, Mary Katherine January 1993 (has links)
The purpose of this study was to determine what relationship exists between the degree of an eating disorder or "disordered eating" pattern and athletic performance. The subjects were 30 female collegiate swimmers, between the ages of 18 and 22 years, at Ball State University, Muncie, Indiana. The subjects completed the Eating Disorder Inventory (EDI) questionnaire, which assesses several psychological and behavioral traits associated with bulimia nervosa and anorexia nervosa, and the Bulimia Test-Revised (BULIT-R) questionnaire which measures symptoms of bulimia in adolescents and adults. A performance score was calculated from each swimmer's best event.The results of this study supported the research hypothesis that there would be a negative relationship between the swimming performance of athletes and degree of eating disorder or "disordered eating" pattern as measured by the two questionnaires. "Disordered eating" patterns predicted 20 percent of the variance in athletic performance. / School of Physical Education

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