Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 6 uppsatser.

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 139-159).

O treinamento de força promove hipertrofia muscular esquelética e aumento da capacidade de gerar força. É preconizado que a ocorrência dessas adaptações depende da especificidade do estímulo de treinamento. De acordo com esse princípio, é esperado que as respostas adaptativas fossem específicas ao estímulo aplicado. Entretanto, tem sido observado, por exemplo, que os modelos de treinamento de força e treinamento de potência, relacionados especificamente a adaptações centrais, induzem semelhantes ganhos em força e hipertrofia. Diante dessas evidências, surgiram questionamentos sobre a validade desse princípio. Nesse sentido, o presente estudo teve como objetivo avaliar o efeito do treinamento de força e potência sobre a expressão do gene da miostatina (MSTN), associada ao controle do tamanho do músculo esquelético, e de genes relacionado a essa via de sinalização: FLST, FL3, GASP-1, ActIIB, SMAD-7 e FOXO-3A. Homens saudáveis, fisicamente ativos, foram randomicamente distribuídos, de forma balanceada, em três grupos: controle, força e potência. Os grupos treinados foram submetidos a oito semanas de intervenção (treinamento de força e treinamento de potência). Foram coletadas amostras de tecido muscular (vasto lateral) via biópsia percutânea nas condições pré e pós-treinamento. Essas amostras foram utilizadas para a análise da expressão de genes envolvidos na sinalização da MSTN por meio da PCR em tempo real. Não foi verificada alteração na expressão gênica de MSTN, ActIIB, GASP-1 e FOXO-3A após o treinamento de força e o treinamento de potência. Porém, foram observadas alterações no conteúdo de RNAm para FLST, FL3 e SMAD-7. Essas alterações foram semelhantes entre os distintos protocolos de treinamento. Os resultados do presente estudo sugerem que ambos os modelos de treinamento de força são capazes de induzir resposta similar sobre a expressão de genes envolvidos na sinalização da MSTN. A ausência de respostas específicas dentro do período investigado aponta para a necessidade de investigar o curso temporal das adaptações aos diferentes modelos de treinamento de força em longo prazo / Resistance training promotes skeletal muscle hypertrophy and increased ability to generate force. It is recommended that the occurrence of these adaptations depend on the specificity of the training stimulus. According to this principle, it is expected that the adaptive responses were specific to stimuli applied. However, it has been observed, for example, that models of strength training and power training, specifically related to central adaptations, induce similar gains in strength and hypertrophy. Given this evidence, questions arose about the validity of this principle. In this sense, the present study aimed to evaluate the effect of strength training and power on the expression of the myostatin gene (MSTN) associated with the control of skeletal muscle size and genes related to this signaling pathway: FLST, FL3, GASP-1, ActIIB, SMAD-7 and FOXO-7-3A. Men healthy, physically active, were randomly divided into three groups: control, strength and power. The trained groups underwent eight weeks of intervention (strength training and power training). Samples pre-and post-training were collected from muscle tissue by percutaneous biopsy of the vastus lateralis. These samples were used for analysis of the expression of genes involved in signaling MSTN by real time PCR. No change was observed in gene expression of MSTN, ActIIB, GASP-1 and FOXO-3A after strength training and power training. However, changes were observed in the content of mRNA for FLST, FL3 and SMAD-7. These changes were similar among the different training protocols. The results of this study suggest that both models of resistance training are able to induce a similar response on the expression of genes involved in signaling MSTN. The absence of specific responses within the investigated period points to the need to investigate the time course of adaptations to different models of resistance training in the long term

There is no single test clinically available that is independently diagnostic for multiple sclerosis (MS). Currently MS is diagnosed using a combination of clinical evaluation and investigations including magnetic resonance imaging (MRI), interpreted in accordance with diagnostic criteria, to demonstrate the requisite dissemination of lesions in (anatomical) space and time. Lesions comprising inflammatory demyelination in the central nervous system are a core pathological feature of MS. Ultra-high field (e.g. 7 Tesla or 7T) T2*-weighted MRI can demonstrate in vivo a central vein in most of these lesions. This is a histopathologically specific feature which could be exploited to improve diagnostic workup in cases of suspected inflammatory demyelination. Central nervous system white matter not involved in demyelinating lesions is nevertheless affected in MS. The mechanisms inflicting injury to this normal appearing white matter (NAWM) and how they relate to focal lesions are unclear. Damage to NAWM seems important, because it correlates well with disability. Any association between cortical lesions, focal white matter lesions (WML) and diffuse damage to NAWM is difficult to investigate in vivo in MS, principally because MRI is relatively insensitive to cortical lesions. Investigation of such associations may also be confounded by the presence of small focal lesions within the “NAWM” that may remain undetected when using conventional MRI to define NAWM. Advantages inherent to ultra-high field MRI might help mitigate both of these problems.

Within team sports, coaches aim to improve physical preparation by optimising the training process specific to competition. Unfortunately, at the elite level of wheelchair rugby (WCR) evidence-based information to guide this process is currently lacking. The present thesis investigates measures of external load during elite competition and explores whether this can be translated to inform current training practices. The first study established the suitability of a radio frequency-based, indoor tracking system (ITS) for the collection of movements specific to WCR. Minimal relative distance errors (< 0.2%) were seen across different sampling frequencies. Peak speed displayed the greatest relative error in 4 Hz tags (2%), with significantly lower errors observed in higher frequency tags (< 1%). The ITS was therefore deemed an acceptable tool for quantifying external load specific to WCR using a sampling frequency of 8 or 16 Hz. The external demands of elite competition were determined in Chapters 4 and 5. Notable differences in the volume of activity were displayed across the International Wheelchair Rugby Federation (IWRF) classification groups. However, the specific positional requirements of low-point (LP) and high-point players (HP) appeared to influence the intensity of external load (Chapter 4). Chapter 5 extended this work and established that peak speed and the ability to perform at high-intensities were best associated with successful mobility performance in WCR, as defined by team rank. This was further shown to be roledependent, whereby high-ranked HP players achieved greater peak speeds and performed more high-intensity activities (HIA) than respective lower-ranked players. Comparisons between the current external demands of training were then compared to that of competition (Chapter 6). Conditioning drills were shown to exceed the demands of competition, irrespective of classification. Notable differences in skill-based and game related drills were displayed across player classifications, whereby both were shown to be roledependent. Although game-simulation drills provided the best representation of competition, the duration appeared important since this factor influenced the results (Chapter 6). When the format of these drills were further modified (Chapter 7), drills containing fewer players increased the volume and intensity of training, specifically in HP. Whilst a 30-second shotclock elicited no changes in external load, differences were revealed when the shot-clock was further reduced to 15-s. Coaches can therefore modify the external training response by making subtle changes to the format of game-simulation drills. This thesis revealed that functional classification and positional-role are key factors during competition, and training should therefore be structured with this in mind. Conditioning drills can be used to elicit a progressive overload in the external responses, whilst game-simulation drills can provide the best representation of competition. Given the importance of gamesimulation drills, the combination of different formats throughout training sessions are critical in order to maximise the preparation of elite WCR players.

Introdução: A avaliação de fragilidade requer medidas mensuráveis de alguns critérios. Em nosso meio, sabe-se que a utilização destas medidas, em larga escala, não será facilmente operacionalizada por dificuldades logísticas. Diante disso, estuda-se a possibilidade de identificação da síndrome de fragilidade por meio de questões subjetivas. Objetivo: Validar componentes subjetivos para avaliação de fragilidade. Método: Este estudo é parte do Estudo SABE - Saúde, Bem-estar e Envelhecimento, realizado no município de São Paulo, Brasil. Trata-se de um corte transversal, com 433 idosos (idade 75 anos), em 2009. Foi adotado o Fenótipo de fragilidade proposto por Fried e colaboradores como padrão-ouro (avaliando objetivamente 5 critérios: perda de peso não intencional, fadiga relatada, redução da força de preensão, redução da velocidade de caminhada e baixa atividade física). Neste modelo, o idoso com um ou dois componentes foi considerado frágil, e com três ou mais era frágil. A avaliação subjetiva foi realizada por meio de questões dicotômicas referentes a cada componente. Calculou-se confiabilidade, sensibilidade, especificidade e valores preditivos positivo e negativo, para análise psicométrica da avaliação subjetiva. Resultados: A avaliação subjetiva é confiável e válida. Para os idosos classificados como pré-frágeis a sensibilidade foi de 89,7 por cento e especificidade de 24,3 por cento ; enquanto para os frágeis, a sensibilidade foi de 63,2 por cento e especificidade de 71,6 por cento . Ao analisar o processo de fragilização (pré-frágil+frágil) quase 90 por cento dos idosos frágeis foram detectados na avaliação subjetiva, 85,2 por cento foram preditos positivamente e 32,7 por cento foram preditos negativamente. Conclusão: A avaliação subjetiva de fragilidade é uma boa ferramenta para identificar processo de fragilidade em idosos / Introduction: The evaluation of frailty measures requires some measurable criteria. In our environment, it is known that the use of these measures on a large scale is not easily operationalized, due to logistical difficulties. Thus, we study the possibility of identifying the syndrome of frailty through subjective questions. Objective: To validate the subjective components for evaluation of frailty. Method: This study is part of the SABE Study - Health, Well-being and Ageing, held in São Paulo, Brazil. This is a cross sectional study of 433 elderly (age 75 years) in 2009. We adopted the phenotype of frailty proposed by Fried and colleagues as a gold standard (measuring objectively 5 criteria: unintentional weight loss, fatigue reported, reduced grip strength, reduced walking speed and low physical activity). In this model, elderly with one or two components were considered frail, and those with three or more were considered frail. Subjective evaluation was performed using dichotomous questions for each component. We calculated the reliability, sensitivity, specificity and positive and negative predictive values for psychometric analysis of subjective evaluation. Results: The subjective evaluation is reliable and valid. For the pre-frail elderly the sensitivity was 89.7 per cent and specificity of 24.3 per cent , while for the frail, the sensitivity was 63.2 per cent and specificity of 71.6 per cent . When analyzing frailty process (pre-frail+frail) almost 90 per cent of the frail elderly were detected in the subjective assessment, 85.2 per cent were predicted positively and 32.7 per cent were predicted negatively. Conclusion: The subjective evaluation of frailty is a good tool to identify frailty process in elderly