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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.
91

Medidas da rotação interna glenoumeral em tenistas e em nadadores assintomáticos comparados com um grupo-controle

Torres, Renato Rangel January 2008 (has links)
Introdução: O déficit de rotação interna glenoumeral, freqüentemente observado em praticantes de esportes que envolvem movimentos repetidos do membro superior sobre a cabeça, tem sido associado ao surgimento de lesões secundárias no ombro. Objetivos: Medir e comparar a amplitude de rotação interna glenoumeral em praticantes assintomáticos de tênis e natação, esportes com características diferentes, mas que envolvem esse tipo de movimento. Métodos: 54 voluntários assintomáticos do sexo masculino (108 ombros) divididos em 3 grupos (tenistas, nadadores, grupo-controle) foram submetidos à medida da amplitude de rotação interna glenoumeral através do método de exame clínico com estabilização da escápula (delineamento de pesquisa: estudo transversal). Foram comparadas as medidas dos ombros dominante e não dominante dentro de cada grupo e entre os grupos. Resultados: Em todos os grupos, o ombro dominante apresentou déficit de rotação interna se comparado com o não dominante. No grupo de tenistas o déficit médio foi de 23,9° ± 8,4° (P< 0,001), no de nadadores foi de 12° ± 6,8° (P< 0,001), e no grupocontrole de 4,9° ± 7,4° (P= 0,035). Comparados os membros dominantes entre os grupos, houve diferença entre todos, sendo o déficit apresentado pelos tenistas em relação ao grupo-controle (27,6°;P< 0,001) maior do que o dos nadadores (17,9°; P<0,001); entre tenistas e nadadores, foi de 9,7°;P=0,002). Conclusões: O membro dominante apresentou menor amplitude de rotação interna glenoumeral do que o não dominante em todos os grupos, sendo o déficit dos tenistas cerca de duas vezes maior do que o dos nadadores. A diferença média entre os membros no grupo controle foi menor do que 5°, o que está dentro do parâmetro de normalidade de acordo com a maioria dos estudos. Todos os grupos apresentaram diferenças se comparados os membros dominantes entre si. Os tenistas apresentaram a menor amplitude de rotação interna seguidos pelos nadadores. / Background: Glenohumeral internal rotation deficit, often diagnosed in players of overhead sports, has been associated with the development of secondary shoulder pathologies. Aim: To measure and compare the range of glenohumeral internal rotation motion in asymptomatic tennis players and in swimmers, different sports that share this overhead movements. Methods: Fifty-four asymptomatic male volunteers (108 shoulders) divided in 3 groups (tennis players, swimmers, control group) underwent measurements of glenohumeral internal rotation using clinical examination with scapular stabilization (study design: cross-sectional study). Measurements of dominant and nondominant shoulders were compared within and between groups. Results: In tennis players, mean déficit was 23.9° ± 8.4° (P< 0.001); in swimmers, 12° ± 6.8° (P< 0.001); and in the control group, 4.9° ± 7.4° (P= 0.035). Dominant shoulders showed significant difference between all groups, and the déficit of the group of tennis players in comparison with the control group (27.6°;P< 0.001) was greater than the deficit found in the group of swimmers (17.9°; P<0.001); between tennis players and swimmers, the deficit was 9.7°;P=0.002). Conclusions: Dominant limbs showed less glenohumeral internal rotation than the nondominant limbs in all groups, being the deficit in the group of tennis players about twice the deficit found for swimmers. Mean difference between limbs in the control group was less than 5°, which is within normal parameters according to most studies. There were statistically significant differences between all groups when dominant shoulders were compared to each other. Tennis players had the least range of motion, followed by swimmers.
92

Electrogenerated chemiluminescence : from mechanistic insights to bioanalytical applications / Electrochimiluminescence : de la compréhension mécanistique aux applications bioanalytiques

Sentic, Milica 26 November 2015 (has links)
La chimiluminescence électrogénérée (ECL) est une technique analytique puissante exploitée pour la détection autant au niveau industriel que dans le domaine de la recherche scientifique ou du diagnostic clinique. La sensibilité élevée et la bonne sélectivité de cette technique font de l'ECL une méthode analytique de choix pour un large éventail d'applications, dont la plus importante est son utilisation commerciale dans un grand nombre de tests immunologiques à base de billes fonctionnalisées. Dans cette thèse, nous avons cherché à étudier le phénomène ECL et son application pour le développement de nouvelles techniques analytiques.Dans la première partie de ce travail, nous utilisons les techniques d'imagerie pour étudier les mécanismes ECL se produisant sur les billes utilisées pour les tests immunologiques. La cartographie de la réactivité au niveau d'une seule microparticule fonctionnalisée avec un complexe de ruthénium fournit une nouvelle stratégie visant à tester l'efficacité du co-réactif et montre des effets optiques associés de focalisation.Dans la deuxième partie, la conception d'un test immunologique pour la détection de l'anti-transglutaminase pour le diagnostic de la maladie coeliaque est présentée en utilisant des ensembles de nanoélectrodes comme plates-formes bioélectroanalytiques. Nous avons également étudié les caractéristiques de l'ECL générée par des réseaux de nanoélectrodes dopées au bore-diamant en tant que matériaux prometteurs pour des applications biologiques ainsi que l'efficacité ECL de deux co-réactifs sur ces réseaux.L'électrochimie bipolaire est un processus sans contact que nous avons exploité pour contrôler le mouvement d'objets conducteurs exposés à un champ électrique en l'absence de contact ohmique direct. Dans la troisième partie de ma thèse, nous présentons l'ECL couplée à l'électrochimie bipolaire pour le suivi d’objets autonomes luminescents. Nous avons élargi ce concept à la détection enzymatique dynamique de glucose en utilisant l'émission de lumière ECL comme signal analytique. / Electrogenerated chemiluminescence (ECL) is a powerful analytical technique exploited for clinical, industrial and research applications. The high sensitivity and good selectivity, makes ECL a tool-of-choice analytical method for a broad range of assays, most importantly for a large number of commercialized bead-based immunoassays. In the present thesis, we aimed to study the ECL phenomenon and its application in development of new analytical methods.In the first part of this work, we used an imaging technique to investigate the ECL mechanisms operating in bead-based assays. Spatial reactivity mapping at the level of a single functionalised bead provides a new strategy to test the co-reactant efficiency and shows associated optical focusing effects.In the second part, the design of a novel anti-transglutaminase ECL immunoassay for celiac disease diagnostic is shown using nanoelectrode ensembles as bioelectroanalytical platforms. We also studied the characteristics of ECL generated by arrays of boron-doped-diamond nanoelectrodes (BDD NEAs) as a promising materials for bioapplications. The ECL efficiency of two co-reactants at BDD NEAs was investigated.Finally, bipolar electrochemistry is a ‘‘wireless’’ process that was exploited for the controlled motion of conductive objects exposed to an electric field in the absence of direct ohmic contact. In the third part of the thesis, we report ECL coupled to bipolar electrochemistry for tracking the autonomous trajectories of swimmers by light emission. We further expanded this concept for dynamic enzymatic sensing of glucose concentration gradient using ECL light emission as an analytical readout.
93

Examining How Specific Involvement Opportunities Influence the Sport Commitment Type of Masters Swimmers: Differences in Number, Strength, and Direction of Associations to Functional and Obligatory Commitment

Bennett, Angela January 2014 (has links)
This thesis aimed to: (a) design a factorially valid survey to assess sub-themes relating to ‘involvement opportunities’ (IOs), which are an antecedent variable in the sport commitment model (Wilson et al., 2004); (b) examine the placement of enjoyment alongside IOs in the sport commitment model; (c) determine the pathways (i.e., direct and/or indirect) by which specific IOs sub-themes affect functional and obligatory commitment and if they differ in number, strength and direction of association (Choosakul et al., 2009); and (d) examine differences between recent initiates compared to those who have been more continuously involved (Chu & Wang, 2012) in Masters swimming. Based on exploratory and confirmatory factor analyses of survey data from 725 swimmers (260 males, 465 females, M age = 50.5, range = 25-92), results confirmed a 10 factor solution of IOs sub-themes. Structural equation modeling demonstrated that the number, direction, and strength of associations between specific IOs sub-themes and commitment vary depending on commitment type, as do the nature of direct and indirect pathways affecting commitment. Invariance testing showed recent initiates and continuously-involved swimmers to be invariant across measurement and structural models. Overall, results support the need to measure and assess IOs at the level of the sub-theme and to consider a bi-dimensional (Santi et al., 2014; Wilson et al., 2004) sport commitment model.
94

"Potência aeróbia de crianças e jovens" / AEROBIC POWER IN CHILDREN AND YOUTHS

Emilson Colantonio 18 April 2006 (has links)
O objetivo geral do presente estudo foi analisar o comportamento dos valores do pico de consumo de oxigênio (VO2pico) e de lactato, em grupos de crianças e jovens não praticantes de natação e atletas de natação no período etário de sete a 17 anos de idade; e ainda, a) investigar as possíveis diferenças entre os valores de VO2pico dos grupos durante o período etário citado em relação ao gênero e ao treinamento sistemático, b) analisar a influência da massa corporal total na variação do VO2pico em função da idade, gênero e treinamento para o período etário citado, c) analisar a influência da massa corporal total na variação do VO2pico tendo como fator interveniente à gordura corporal, d) analisar as concentrações de lactato no sangue após esforço gradualmente crescente até a exaustão para o período etário citado. O delineamento utilizado foi transversal e contou com uma amostra de 145 crianças e jovens de sete a 17 anos de idade, com no mínimo três sujeitos de cada idade e gênero que foram subdivididos em dois grupos – controle (escolares) e experimental (nadadores).Cada grupo foi subdividido em três grupos etários (sete a 10, 11 a 14 e 15 a 17 anos) perfazendo 12 subgrupos (seis no feminino e seis no masculino). Após aprovação de Comissão de Ética Institucional e assinatura do termo de consentimento informado os voluntários realizaram uma anamnese para avaliar o histórico de saúde. Em laboratório, foram realizadas medidas antropométricas, eletrocardiograma de repouso e teste funcional em esteira para a avaliação da aptidão cardiorespiratória – VO2pico. Os resultados foram apresentados de forma descritia e inferencial como análise descritiva, diagramas box-plot, ANOVA e ANCOVA. O programa estatístico usado foi o SPSS versão 11.0. O nível de significância adotado foi 0,05. Os valores médios de VO2picoabs, VO2picorelcor e VO2picorelcor ajustado entre crianças e jovens de diferentes faixas etárias de escolares e nadadores em ambos os gêneros não são equivalentes, com exceção das meninas da faixa etária de sete a 10 anos. O delta de lactato (repouso e pós exercício) é dependente do gênero, faixa etária e grupo de treinamento. Os valores de VO2pico em escolares e nadadores sofrem influência da idade e do gênero. Os valores de VO2pico das crianças e jovens de sete a 17 anos de idade escolares e nadadores para diferentes faixas etárias sofrem influência da massa corporal total, em especial da somatória de dobras cutâneas periféricas, tendo como fator interveniente a gordura corporal. As variáveis de delta de lactato e somatória de dobras cutâneas consideradas como covariáveis levaram ao estabelecimento do modelo para VO2picorelcor (ml.kg-1.min-1) e VO2picorelcor ajustado (ml.kg-0,67.min-1) com R2 elevados, mas maiores no último caso. / The general aim of this study was to analyze the behavior of the peak oxygen uptake (VO2peak) values and lactate, in children and youths groups no swimming practitioner and swimming athletes from seven to 17 years age group; and even, a) to investigate the possible differences among VO2peak values of groups during this age group related to gender and systematic training, b) to analyze the influence of total body mass in VO2peak variation related to the age, gender and training for this age group, c) to analyze the influence of total body mass in VO2peak variation having as interventional factor the body fat, d) to analyze the blood lactate concentrations after growing gradually effort until exhaustion for this age group. The cross-sectional experimental design had a sample with 145 children and youths from seven to 17 years old, with three subjects at least of each age and gender subdivided in two groups – control (pupils) and experimental (swimmers). Every group was subdivided in three age groups (7-10, 11-14 and 15-17 years) making 12 sub-groups (6 female and 6 male). After approved Institutional Ethical Boarding and Informed Consent signed, the volunteers were submitted the anamnesis for participation health screening. In the lab, were performed anthropometrical measurements, rest electrocardiogram and functional test on a treadmill to asses the cardiorespiratory fitness – VO2peak. The results were presented on a descriptive and inferential way like descriptive analyses, diagrams box-plot, ANOVA e ANCOVA. The statistic program used was the SPSS version 11.0. The significance level adopted was 0,05. The VO2peakabs, VO2peakrelcor e VO2peakrelcor adjusted means values between children and youths of different age groups pupils and swimmers in both genders are not equivalent, with exception on the girls from seven to 10 years old age group. The lactate delta (rest and after exercise) is dependent of the gender, age group and training group. The VO2peak means values in pupils and swimmers suffer influence of the age and the gender. The VO2peak values of the children and youths from seven to 17 years old pupils and swimmers for different age groups suffer influence of the total body mass, in special of the peripheral skinfolds sum, having as interventional factor the body fat. The variables lactate delta and skinfolds sum here considered like covariate leaded to the establishment of the model for VO2peakrelcor (ml.kg-1.min-1) and VO2peakrelcor adjusted (ml.kg-0,67.min-1) with higher R2, but greater in the last case.
95

Collegiate female swimmers attitudes toward gender and coaching

Barber, Erica January 2002 (has links)
There is great controversy regarding the methods in attenuating the epidemic of being overweight and obese among our population. For years, low-fat diets have been prescribed as the best approach to solving this problem, however, low-carbohydrate diets have become increasingly popular despite the widespread opinion that they result in large reductions in muscle tissue and function. The purpose of this study was to compare the effects of a Step-I and carbohydrate-restricted (ketogenic) diet on changes in body mass (BM), fat mass (FM), lean body mass (LBM), and resting metabolic rate (RMR). Eight overweight men (>25% body fat) consumed Step-I (<30% fat) and ketogenic (<10% carbohydrate) diets for 6 weeks in a randomized cross-over design. Body composition (dual energy X-ray absorptiometry) and RMR were examined before and after each diet. Energy intake was significantly reduced during the Step-I (1506 kcal/day) and ketogenic (1766 kcaL'day) diets compared to habitual dietary intake (2443 kcal/day). The following changes in body composition were observed during the Step-I and ketogenic diets, respectively: BM -4.1 and -5.9 kg, FM -3.5 and -4.4kg, LBM +0.1 and -1.7kg. The changes in RMR for the Step-I and ketogenic diets respectively were -155 and -26 kcal/day, relative RMR -0.68 and +0.81 kcal/kg BM. Although changes in BM, LBM, and FM tended to be greater during the ketogenic diet and changes in both absolute and relative RMR tended to be greater during the Step-I diet, no significant differences were noted between diets. These data indicate that hypoenergetic diets greatly differing in macronutrient distribution result in similar changes in body composition and that very low-carbohydrate diets do not result in significant losses in LBM and metabolic rate. / School of Physical Education
96

Upper body strength and endurance and its relationship with freestyle swim performance in elite swimmers

Storck, Natalie January 2017 (has links)
Background: Strength is considered an important part in swimming and is usually included in training programs for swimmers. However, studies assessing the relationship between muscle strength, muscle endurance and swim performance are not many and have showed different results. Aim: The aim of this study was to assess the correlation between bench press, pull-up and 400 meter freestyle swim performance in elite swimmers. Method: The subjects (n=15, age 16-20) performed a one repetition maximum (1RM) bench press test to measure maximal muscle strength and to measure muscle endurance the subjects performed as many pull-up repetitions as possible during 30 seconds. A velocity four (V4) speed test was performed to assess swim performance by measuring time over covered distance and blood lactate levels. Results: The results of this study showed a moderate correlation (r=-0.54) between one repetition maximum in bench press and 400 meter freestyle swim performance. It showed a strong correlation (r=-0.63) between number of pull-ups repetitions during 30 seconds and 400 meter freestyle swim performance. Conclusion: These results suggest that upper body strength contributes to swim performance over 400 meter. The stronger correlation between pull-ups and swimming may indicate that muscle endurance of m. latissimus dorsi and the back muscles may be important to incorporate in a training program since it has shown to have a strong correlation with swim performance at 400 meters. / Bakgrund: Styrka anses vara en viktig del i simning och är ofta inkluderat i träningsprogram för simmare. Dock har endast ett mindre antal studier undersökt relationen mellan muskelstyrka, muskel uthållighet och simprestation och de som har gjort det visar olika resultat. Syfte: Syftet med denna studie var att utvärdera korrelationen mellan bänkpress, pull-ups och 400m simprestation hos elitsimmare. Metod: Deltagarna (n=15, ålder 16-20) utförde ett en repetition maximum (1RM) i bänkpress för att mäta maximal muskel styrka och för att mäta muskeluthållighet utförde deltagarna så många pull-ups repetitioner som möjligt under 30 sekunder. Ett velocity four (V4) hastighets test utfördes för att utvärdera simprestation genom att mäta tid över simmad distans och blod laktat värden. Resultat: Resultatet i denna studie visade på en moderat korrelation (r=-0,54) mellan en repetition maximum i bänkpress och 400 meter fristil simprestation. Den visade på en stark korrelation (r=-0,63) mellan antalet pull-ups repetitioner under 30 sekunder och 400 meter fristil simprestation. Konklusion: Dessa resultat tyder på att överkroppsstyrka bidrar till simprestation över 400 meter. Den starkare korrelationen mellan pull-ups och simning kan indikera att muskeluthållighet hos m. latisimus dorsi och ryggmusklerna kan vara viktigt att lägga in i ett träningsprogram då det visat på en stark korrelation till simprestation på distansen 400 meter.
97

Active colloids and polymer translocation

Cohen, Jack Andrew January 2013 (has links)
This thesis considers two areas of research in non-equilibrium soft matter at the mesoscale. In the first part we introduce active colloids in the context of active matter and focus on the particular case of phoretic colloids. The general theory of phoresis is presented along with an expression for the phoretic velocity of a colloid and its rotational diffusion in two and three dimensions. We introduce a model for thermally active colloids that absorb light and emit heat and propel through thermophoresis. Using this model we develop the equations of motion for their collective dynamics and consider excluded volume through a lattice gas formalism. Solutions to the thermoattractive collective dynamics are studied in one dimension analytically and numerically. A few numerical results are presented for the collective dynamics in two dimensions. We simulate an unconfined system of thermally active colloids under directed illumination with simple projection based geometric optics. This system self-organises into a comet-like swarm and exhibits a wide range of non- equilibrium phenomena. In the second part we review the background of polymer translocation, including key experiments, theoretical progress and simulation studies. We present, discuss and use a common model to investigate the potential of patterned nanopores for stochastic sensing and identification of polynucleotides and other heteropolymers. Three pore patterns are characterised in terms of the response of a homopolymer with varying attractive affinity. This is extended to simple periodic block co-polymer heterostructures and a model device is proposed and demonstrated with two stochastic sensing algorithms. We find that mul- tiple sequential measurements of the translocation time is sufficient for identification with high accuracy. Motivated by fluctuating biological channels and the prospect of frequency based selectivity we investigate the response of a homopolymer through a pore that has a time dependent geometry. We show that a time dependent mobility can capture many features of the frequency response.
98

Liquid Crystals in Aqueous Ionic Surfactant Solutions: Interfacial Instabilities & Optical Applications

Peddireddy, Karthik Reddy 12 May 2014 (has links)
No description available.
99

Calibração de câmeras para análises subaquáticas de movimentos = Cameras calibration for underwater motion analysis / Cameras calibration for underwater motion analysis

Silvatti, Amanda Piaia, 1983- 02 July 2013 (has links)
Orientador:Ricardo Machado Leite de Barros / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Física / Made available in DSpace on 2018-08-21T23:09:57Z (GMT). No. of bitstreams: 1 Silvatti_AmandaPiaia_D.pdf: 2153043 bytes, checksum: bfa39ebf2fe3e82ab53b434c5a4e6d8a (MD5) Previous issue date: 2013 / Resumo: Para análises subaquáticas de movimentos tridimensionais é necessária uma calibração precisa de grandes volumes. Métodos baseados em modelos lineares de câmeras são comumente utilizados na biomecânica e para isso faz-se necessário a construção, o transporte e a medição de estruturas rígidas, o que se torna mais difícil quando volumes maiores estão envolvidos. Recentemente, métodos alternativos baseados em modelos não-lineares de câmeras, foram propostos para resolver este aspecto. Assim, os objetivos deste trabalho foram 1) avaliar a exatidão da reconstrução tridimensional fora e dentro da água utilizando o método proposto por Zhang (2000); 2) avaliar a exatidão dos métodos não-lineares para a calibração de câmeras propostos por Hatze, 1988, Cerveri, et al., 1998 e Zhang, 2000 para aplicações com câmeras submersas e os efeitos da variação da posição no volume de calibração sobre a exatidão de reconstrução tridimensional dos métodos e ressaltando, ainda as vantagens e desvantagens de cada método e 3) testar a aplicabilidade dos métodos não-lineares propostos por Cerveri et al., 1998 e Zhang, 2000 para a reconstrução da trajetória da mão de nadadores em diferentes nados. Para aquisição dos dados foi utilizado um sistema de análise cinemática (DVideo), que foi adaptado para aquisição de imagens submersa. O sistema consiste de computadores ligados em câmeras (Basler) para aquisição online de dados. Caixa-estanques especialmente desenvolvidas para o modelos das câmeras foram utilizadas para proteção e um genlocker trigger foi utilizado para a sincronização das câmeras. Tripés para sustentação e fixação das câmeras foram adaptados com ventosas para fixação no fundo da piscina. Para a correção da distorção foram implementados em Matlab os métodos não-lineares para a calibração de câmeras. Um teste de barra rígida foi usado para avaliação da exatidão e precisão. Os resultados mostraram que os métodos propostos por Cerveri et al., 1998 (1,16mm a 0,96mm) e Zhang, 2000 (0,73mm) são alternativas promissoras para análise tridimensional de movimentos subaquáticos. Ambas as metodologias apresentaram resultados com maior exatidão que os encontrados na literatura. Este fato ocorreu devido a uma melhor modelagem da distorção óptica que foi confirmada pela menor influência no erro relativo à posição do objeto no volume de aquisição. Quanto à flexibilidade e portabilidade em relação ao objeto de calibração, ambos os métodos usam objetos mais fáceis de construir e manipular do que os objetos tradicionalmente utilizados. O sistema para a análise tridimensional do movimento utilizando câmeras submersas mostrou-se ser adequado para aplicações subaquáticas. Uma vez que, os resultados aqui relatados podem ser imediatamente apreciados pelos treinadores, pois foi possível identificar simetria ou assimetria entre os dois lados, a variabilidade intra e inter-sujeitos em termos de padrões de movimento e concordância ou discordância com o modelo teórico. Importante ressaltar que existe a possibilidade de extensão da análise para os diferentes segmentos corporais e o sistema e os métodos para a calibração de câmeras apresentados neste trabalho podem ser utilizado para qualquer esporte ou atividade realizada na água, como por exemplo, hidroginásticas ou práticas de reabilitação / Abstract: In order to perform a three-dimensional motion analysis in underwater conditions is necessary to calibrate accurately large volumes. Methods based on linear camera models are commonly used in biomechanics and this requires to construct, to transport and to measurement rigid structures, which becomes more difficult when larger volumes are involved. Recently, alternative methods based on nonlinear camera models have been proposed to address this aspect. The aims of this study were 1) to evaluate the accuracy of 3D reconstruction out and underwater using the method proposed by Zhang (2000); 2) to evaluate the accuracy of nonlinear camera calibration methods proposed by Hatze, 1988, Cerveri, et al., 1998 and Zhang, 2000 for underwater applications using submerged cameras and the effects of object position in the acquisition volume on the accuracy of 3D reconstruction methods, highlighting the advantages and disadvantages of each method, and 3) to test the applicability of the nonlinear methods proposed by Cerveri et al., 1998 and Zhang, 2000 for the reconstruction of the swimmers hand trajectory in different swims styles. For data acquisition, we used a kinematic analysis system (DVideo), which was adapted for underwater conditions. The system consists of cameras (Basler) connected in computers for online data acquisition. Waterproof housings were specially designed to protect the cameras and a genlocker trigger was used to synchronize the cameras. Tripods to support and to fix the cameras were adapted with suction cups and were used to fix them on the swimming pool floor. In order to perform the distortion correction the nonlinear camera calibration methods were implemented in Matlab software. A rigid bar test was used to assess the accuracy and precision. The results showed that the methods proposed by Cerveri et al. 1 998 (1.16 mm to 0.96 mm) and Zhang, 2000 (0.73 mm) are promising alternatives for 3D underwater motion analysis. Both methodologies presented results with greater accuracy than those found in the literature. This occurred due to an improvement of the distortion modeling and that was confirmed by the smallest influence of the object position on the error values. Related to the flexibility and portability of the calibration object, both methods use objects easier to build and manipulate than the objects traditionally used. The 3D motion analysis system using submerged cameras showed to be suitable for underwater applications. The results reported here can be immediately appreciated by coaches, because it was possible to identify symmetry or asymmetry between the two sides, the variability within and between subjects in terms of movement patterns and agreement or disagreement with the theoretical model. Important to emphasize that there is the possibility of extending the analysis for different body segments and the system and the camera calibration methods presented in this work can be used for any sport or activity performed in water, such as hydro gymnastic or rehabilitation practices / Doutorado / Biodinamica do Movimento Humano / Doutor em Educação Física
100

The immediate effect of myofascial trigger point dry needling of four shoulder girdle muscles on the 100m lap- times of asymptomatic competitive swimmers in Bloemfontein

Schmidt-Kinsman, Sarah January 2017 (has links)
Submitted in partial compliance with the requirements fo the Master's Degree in Technology: Chiropractic, Durban University of Technology, Durban, South Africa, 2017. / Background Competitive swimming, as with most other sports that are participated in at more than a recreational level, involves a substantial amount of training. Training excessively results in the overuse of muscles. The overuse of muscles commonly causes the production of myofascial trigger points (MFTPs) within the overworked muscles. The presence of MFTPs is a condition known as myofascial pain syndrome (MPS). Myofascial trigger points may be active or latent. Either way, they produce a wide range of effects. This study focuses on the effect of reduced muscle strength. Muscle strength is essential to athletes as it determines performance. Swimmers with MFTPs will not perform at their full ability. Dry needling is an effective form of treatment for MFTPs as it produces immediate relief from the effects of MFTPs. There is not enough information on the immediate effects of dry needling on athlete performance. Since dry needling brings about the immediate relief of MFTPs, this study aims to restore a swimmer’s muscle power and hence improvement of their swimming performance post-intervention. Aim The aim of this study was to determine the immediate effect of dry needling common myofascial trigger points (MFTP) found in four muscles of the shoulder girdle on competitive swimmers’ 100m freestyle lap-times. Methods The design was a pre-test post-test quasi-experimental study. Thirty five competitive swimmers between the ages of 16 and 30 years old participated in this study. Each participant underwent one assessment. Participants’ lap-times were taken using a Sportline Econosport Stopwatch. The pre- and post-intervention lap-times were compared to each other using statistical analysis. The intervention for the purpose of the study was trigger point dry needling. Myofascial trigger points were assessed using manual palpation and the Myofascial Diagnostic Scale (MDS). Results The median lap time was slightly longer post intervention (0:01:16.10) than pre-intervention (0:01:16.03), and was highly statistically significant (p=0.001). The results of the study were inconclusive, however, as there were too many confounding variables (for example, fatigue due to repeatedly swimming laps, swimmers of a lower caliber and hence quicker fatigue rate being included in the study)which negated the effect of dry needling and so the poorer performance of the participants post-intervention could not be attributed entirely to the intervention. A small number of participant’s lap-times decreased post-intervention i.e. they performed better post-intervention. These individualswere predominantly sprint-swimmers. Conclusion Dry needling negatively affects immediate lap-time performance. Future studies should reduce the number of variables affecting the study, for example, having a sprinter versus long-distance swimmer group, testing the outcome of dry needling after the swimmer has had sufficient time (for example, a day) to rest post-intervention. / M

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