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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.
131

Effects Of A Novel, High-Intensity Aerobic Interval Training Program on Diastolic And Cardiovascular Function In Patients With Heart Failure With Preserved Ejection Fraction

January 2012 (has links)
abstract: Heart failure is a major worldwide health concern and is the leading cause of hospitalization among elderly Americans. Approximately 50% of those diagnosed with heart failure have heart failure with preserved ejection fraction (HFPEF). HFPEF presents a therapeutic dilemma because pharmacological strategies that are effective for the treatment of heart failure and reduced ejection fraction have failed to show benefit in HFPEF. Long term moderate intensity exercise programs have been shown to improve diastolic function in patients HFPEF. High intensity interval training (HIIT) has been shown to improve diastolic function in patients with heart failure and reduced ejection fraction. However, the effects of high intensity interval training in patients with HFPEF are unknown. Fourteen patients with HFPEF were randomized to either: (1) a novel program of high-intensity aerobic interval training (n = 8), or (2) a commonly prescribed program of moderate-intensity (MOD) aerobic exercise training (n = 6). Before and after four weeks of exercise training, patients underwent a treadmill graded exercise test for the determination of peak oxygen uptake (VO2peak), a brachial artery reactivity test for assessment of endothelium-dependent flow-mediated dilation (BAFMD), aortic pulse wave velocity assessment as an index of vascular stiffness and two-dimensional echocardiography for assessment of left ventricular diastolic and systolic function. I hypothesized that (1) high-intensity aerobic interval training would result in superior improvements in FMD, aortic pulse wave velocity, VO2peak, diastolic function and, (2) changes in these parameters would be correlated with changes in VO2peak. The principal findings of the study were that a one month long high intensity interval training program resulted in significant improvements in diastolic function as measured by two-dimensional echocardiography [pre diastolic dysfunction (DD) grade - 2.13 + 0.4 vs. post DD grade - 1.25 + 0.7, p = 0.03]. The left atrial volume index was reduced in the HIIT group compared to MOD ( - 4.4 + 6.2 ml/m2 vs. 5.8 + 10.7 ml/m2, p = 0.02). Early mitral flow (E) improved in the HIIT group (pre - 0.93 + 0.2 m/s vs. post - 0.78 + 0.3 m/s, p = 0.03). A significant inverse correlation was observed between change in BAFMD and change in diastolic dysfunction grade (r = - 0.585, p = 0.028) when all the data were pooled. HIIT appears to be a time-efficient and safe strategy for improving diastolic function in patients with heart failure and preserved ejection fraction. These data may have implications for cardiovascular risk reduction in this population. / Dissertation/Thesis / Ph.D. Exercise and Wellness 2012
132

Effects of a Fat-sugar Supplemented Diet, with and Without Exercise Training, on Body Fat Mass and Selected Cardiometabolic Risk Markers in Overweight and Obese, Sedentary Males

January 2016 (has links)
abstract: The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI. / Dissertation/Thesis / Doctoral Dissertation Physical Activity, Nutrition and Wellness 2016
133

Desenvolvimento da força após 12 semanas de treinamento subsequente ao exercício aeróbio intermitente de alta intensidade / Maximum strength development and volume-load during concurrent high intensity intermittent training plus strength or strength-only training

Oliveira, Flaviane Poleto [UNESP] 28 February 2018 (has links)
Submitted by FLAVIANE POLETO DE OLIVEIRA null (fla_vb13@hotmail.com) on 2018-03-24T13:04:27Z No. of bitstreams: 1 Dissertação de mestrado_Flaviane Poleto_versão definitiva.pdf: 677650 bytes, checksum: b1dd23673956cadc620d339f8764038f (MD5) / Approved for entry into archive by Claudia Adriana Spindola null (claudia@fct.unesp.br) on 2018-03-26T12:39:15Z (GMT) No. of bitstreams: 1 oliveira_fp_me_prud.pdf: 677650 bytes, checksum: b1dd23673956cadc620d339f8764038f (MD5) / Made available in DSpace on 2018-03-26T12:39:15Z (GMT). No. of bitstreams: 1 oliveira_fp_me_prud.pdf: 677650 bytes, checksum: b1dd23673956cadc620d339f8764038f (MD5) Previous issue date: 2018-02-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O Treinamento Concorrente (a combinação de exercício aeróbio com treinamento de força) pode resultar em uma interferência negativa no desempenho de força. Além disso, há indicações de que a magnitude dessa interferência é dependente do modo/intensidade do exercício aeróbio. OBJETIVO: Sendo assim, o objetivo deste estudo foi comparar o efeito agudo do Treinamento de Força (TF) e do Treinamento Concorrente (TC) consistidos do Treinamento Intermitente de Alta Intensidade (HIIT) sob os ganhos de força máxima e volume durante 12 semanas. MÉTODOS: A amostra foi composta por 19 homens recreativamente ativos divididos entre o grupo TC (n=11) e grupo TF (n=8). O grupo TC realizou o HIIT (1min de corrida a 100% da velocidade aeróbia máxima intercalado por 1min de recuperação passiva até atingir 5 km) e em seguida uma sessão de treinamento de força constituída por oito exercícios com cargas de 8-12 repetições máximas, enquanto o grupo TF realizou apenas as sessões de treinamento de força. Ambos os grupos treinavam duas vezes por semana durante 12 semanas. A força máxima e o volume de treinamento durante uma sessão aguda foram avaliados pré, após oito e 12 semanas de treinamento. RESULTADOS: Um pequeno efeito de interferência foi observado na força máxima em relação à massa corporal após 12 semanas de treinamento com maiores melhorias no grupo TF quando comparado ao grupo TC. A mesma não foi observada após oito semanas de treinamento. CONCLUSÃO: Esses resultados sugerem que o volume realizado não exerceu impacto nos ganhos de força até oito semanas de treinamento concorrente constituído por HIIT. / The concurrent training (i.e., combination of endurance with strength training) may result in negative interference on strength performance. Moreover, there are indications that the magnitude of this interference is dependent on endurance exercise mode. PURPOSE: The purpose of this study was to compare maximal strength gains and acute volume performed during strength training (ST) and concurrent training (CT) consisting of high-intensity intermittent training plus strength training over the course of a 12-week intervention. METHODS: Nineteen recreationally active males were divided in CT (n=11) and ST (n=8) groups. The CT group performed repeated 1 min efforts at 100% of maximal aerobic velocity interspersed by 1 min of passive recovery until accumulating a total running distance of 5km followed by a strength session (consisting of three sets of eight exercises with loads of 8-12 repetition maximum) twice weekly for a period of 12 weeks, while the ST group performed only strength training sessions. Maximal strength and training volume during an acute exercise session were evaluated at baseline and after eight and 12 weeks of training. A two-way analysis of variance (group and training period) with repeated measures in the second factor was conducted to compare maximal strength values. A three-way analysis of variance (group, training period and set) was conducted to compare the volume performed in the acute exercise sessions. RESULTS: A small interference effect was observed in maximal strength relative to body mass after 12 weeks of training with greater improvements in the ST group compared to the CT group, that were not observed after 8 weeks. The volume performed during the acute exercise session was lower in CT than ST after 8 and 12 weeks of training. In summary, executing high-intensity intermittent exercise before strength training impaired the total volume performed after 8 and 12 weeks compared with strength training alone but the impairment of maximal strength occurred only after 12 weeks. CONCLUSION: These results suggest that the impairment of volume performed did not have an impact on strength gains until after 8 weeks of concurrent training with high-intensity intermittent exercise.
134

Análise da qualidade do selamento apical de canais radiculares irradiados com os lasers de Nd:YAG, diodo ou ER:YAG e obturados com os cimentos resinosos AH Plus™, EndoREZ®, Epiphany® ou Epiphany SE® / Quality analysis of the apical seal of root canals irradiated with Nd: YAG, diode or Er: YAG lasers and filled with AH Plus, EndoREZ®, Epiphany® or Epiphany SE® resin based sealers

Cacio de Moura Netto 11 March 2009 (has links)
O objetivo deste estudo foi analisar a influência da irradiação com lasers de alta intensidade antes da obturação de canais radiculares com cimentos endodônticos resinosos no selamento apical. Raízes permanentes humanas (n=168) foram endodonticamente tratadas e, então, divididas aleatoriamente em quatro grupos experimentais (n=42), de acordo com o tratamento dentinário subsequente. Os grupos foram: GØ (controle) sem tratamento adicional; GN irradiado com o laser de Nd:YAG (1,5 W, 100 mJ, 15 Hz); GD irradiado com o laser de diodo (2,5 W em modo contínuo); GE irradiado com o laser de Er:YAG (1 W, 100 mJ, 10 Hz). Dois espécimes de cada grupo foram preparados para avaliação em microscopia eletrônica de varredura (MEV) convencional para observação morfológica da superfície dentinária apical. Os espécimes remanescentes de cada grupo foram aleatoriamente divididos em quatro subgrupos (n=10), de acordo com o cimento obturador utilizado (AH Plus, EndoREZ®, Epiphany® ou Epiphany SE®). Para a análise de infiltração, os espécimes foram imersos em solução amoniacal de nitrato de prata a 50 % (pH=9,5) por 24 horas. Os valores de infiltração apical, em mm, foram comparados pela ANOVA, seguido pelo teste de Tukey (p<0,05). Cinco secções de cada subgrupo foram aleatoriamente selecionadas e analisadas em MEV em modo ambiental para avaliar a adaptação e penetração do material obturador nas paredes dentinárias. As imagens em MEV ambiental foram classificadas em escores por três avaliadores calibrados. A concordância interexaminadores foi confirmada pelo teste Kappa e os escores foram comparados pelo teste de Kruskal-Wallis (p<0.05). No grupo controle, o cimento EndoREZ® apresentou infiltração de nitrato de prata significantemente menor que todos os outros cimentos (p<0,05), com exceção do Epiphany®. A irradiação com os lasers de Nd:YAG e de diodo diminuiu a infiltração média dos subgrupos obturados com o cimento AH Plus (p<0,05). A irradiação com o laser de Nd:YAG levou a um aumento do nível de infiltração nos subgrupos obturados com EndoREZ® e Epiphany SE®. A adaptação, bem como a penetração dos cimentos, não foram prejudicadas pela prévia irradiação com laser dos canais radiculares, independentemente do laser utilizado. / The aim of this study was to analyze the influence of intracanal high intensity laser irradiation prior to root canal filling with resin based endodontic sealers on the apical sealing. Human dental roots (n=168) were endodontically treated and then randomly divided into four experimental groups (n=42), according to the further dentin surface treatment. The groups were: control (GØ) received no further treatment; GN irradiated with Nd:YAG laser (1.5 W, 100 mJ, 15 Hz); GD irradiated with diode laser (2.5 W in continuous way) and GE irradiated with Er:YAG laser (1 W, 100 mJ, 10 Hz). Two specimens of each group were prepared for conventional scanning electron microscopy (SEM) for morphological observation of the apical dentin surface. The remaining specimens of each group were randomly divided into four subgroups (n=10), according to the sealer used for dental root filling as follows: AH Plus, EndoREZ®, Epiphany® or Epiphany SE®. For leakage analysis, the specimens were immersed into 50 % silver nitrate ammoniacal solution (pH = 9.5) for 24 hours. The values of apical leakage, in mm, were compared by ANOVA followed by Tukeys test (p<0,05). Five sections of each subgroup were randomly selected and analyzed using environmental SEM in order to evaluate the adaptation and penetration of the filling material into the dentin walls. The environmental SEM images were scored by three calibrated examiners. The inter-examiners agreement was confirmed by Kappa test and the scores were compared by Kruskal-Wallis test (p<0.05). At the control group, the EndoREZ® sealer led to significantly smaller silver nitrate leakage in comparison to the others sealers (p<0,05), except by Epiphany®. The irradiation with Nd:YAG and diode lasers reduced the mean leakage of the subgroups filled with AH Plus sealer (p<0,05). Nd:YAG laser irradiation led to a leakage level increase of the subgroups filled with EndoREZ® and Epiphany SE®. The adaptation as well as sealer penetration were not impaired by the root canal prior laser irradiation, independently of the laser used.
135

A influência do estresse experimentado por cavalos de corrida, em determinados momentos de sua rotina, sobre a função imune in vitro / Influence of stress on in vitro immune function in Thoroughbred racehorses

Mônica Cristina Zandoná Meleiro 19 July 2006 (has links)
Embora os cavalos apresentem características excepcionais frente a situações de estresse na natureza, foi considerada a possibilidade do cavalo de corrida ser submetido, por vezes, a alguma situação de estresse, que afetasse sua saúde e bem estar. Foram verificadas alterações do número e da função de populações celulares implicadas com a defesa, principalmente neutrófilos e linfócitos. Trinta cavalos de corrida da raça puro-sangue inglês, locados no Jockey Club de São Paulo, na cidade de São Paulo, foram utilizados. Os animais foram divididos em dois grupos e as amostras de sangue foram coletadas em momentos diferentes da rotina dos animais. No grupo I, foram coletadas amostras onze dias antes da corrida (-11d), imediatamente após a corrida (0d), um dia após a corrida (+1d), dois dias após a corrida (+2d) e três dias após a corrida (+3d). Enquanto, no grupo II as amostras foram coletadas oito dias antes da corrida (-8d), imediatamente após a corrida (0d), um dia após a corrida (+1d) e cinco dias após a corrida (+5d). Foram realizados ensaios de fagocitose e burst oxidativo dos neutrófilos, determinação de cortisol sérico, ensaios de apoptose, linfoproliferação e hemograma. A função de fagocitose, tanto em porcentagem, quanto em intensidade, mostrou-se diminuída nas amostras coletadas imediatamente após a corrida, nos dois grupos de animais. Os valores médios de burst oxidativo das amostras coletadas imediatamente após a corrida, dos animais do grupo I apresentaram-se diminuídos. Não foram encontradas diferenças estatísticas significantes entre os resultados obtidos em relação às células apoptóticas, quando os diferentes momentos foram comparados; o mesmo ocorreu quando foi realizado o confronto dos valores do ensaio de linfoproliferação. Os valores médios dos níveis séricos de cortisol apresentaram-se aumentados no momento imediatamente após a corrida, em relação aos valores dos outros momentos, nos dois grupos de animais. Quanto aos dados de hemograma, houve aumento do número percentual de neutrófilos no momento imediatamente após a corrida quando foi realizada comparação com os demais momentos. Nos cavalos estudados, ainda que tenha sido encontrada uma diminuição transitória na função dos neutrófilos, a função adaptativa não chegou a ser acometida, que sugere que, embora se constitua em um exercício de alta intensidade, a fugacidade da corrida acabe por evitar danos maiores, em animais bem condicionados e adaptados a situações de estresse / Although horses can present exceptional responses during stress situations in nature, it was raised the possibility that racehorses under certain stress conditions could develop changes that may affect their health and welfare. Alterations of the number and function of cells that are involved with the defense response, mainly neutrophils and lymphocytes populations were verified. Thirty Thoroughbred racehorses housed at the Jockey Club de São Paulo, in São Paulo, Brazil, were used in the present study. The animals were divided in two groups and blood samples were collected at different moments of their routine. In group I, the samples were collected eleven days before race (-11d), immediately after race (0d), one day (+1d), two days (+2d) and three days after race (+3d). In group II, the samples were collected eight days before race (-8d), immediately after race (0d), one day (+1d) and five days after race (+5d). Phagocytosis assay and oxidative burst activity of neutrophils, serum cortisol determination, apoptosis and lymphocyte proliferation assay and haematology tests were performed. The percentage and intensity of phagocytosis functions decreased in samples collected immediately after race, in both groups of animals. The mean values of oxidative burst activity of samples collected immediately after race, from animals of group I also decreased. Statistically significant differences between the results were obtained in relation to the apoptotic cells, when compared on different moments and the same occurred in Relation to the lymphocyte proliferation values. The mean values of serum cortisol levels increased at the moment immediately after race when compared with the values of the other moments, in both groups of animals. In relation to the haematologycal values, the percentage of neutrophils was increased at the moment immediately after race when compared with the other moments. Even though a transitory reduction in the neutrophils function has occurred, the adaptive function was not impaired, which suggest that, in spite of the high intensity of this exercise, the short-term race can prevent further damages in well-conditioned and stress-adapted animals
136

Fügen polymerer Packstoffe mit hochintensivem fokussierten Ultraschall

Oehm, Lukas 09 October 2017 (has links) (PDF)
Das Verschließen besitzt als finaler qualitätsbestimmender Prozess besondere Bedeutung in der Verpackungstechnik. Da nach wie vor Kunststoff der am häufigsten eingesetzte Packstoff in der Lebensmittel- und Pharmaindustrie ist, sind insbesondere für das stoffschlüssige Fügen polymerer Packstoffe zahlreiche Verfahren etabliert. Alle bekannten Verfahren besitzen jedoch Einschränkungen bei deren Anwendung oder stellen spezifische Anforderungen an den Packstoff wie beispielsweise das Vorhandensein polarer oder elektrisch leitender Schichten im Verbundaufbau. Wissenschaftliche Untersuchungen haben das Ziel, die bestehenden Einschränkungen durch die Schaffung von Prozessverständnis und darauf aufbauender Optimierung der Verfahren und Prozesse zu verringern oder zu beseitigen. Alternativ dazu erscheint es sinnvoll, neue, bisher nicht in der Verarbeitungstechnik eingesetzte Verfahren auf deren Anwendbarkeit für verpackungstechnische Prozesse im Bereich des Fügens hin zu prüfen. Hochintensiver fokussierter Ultraschall (HIFU) ist ein solches interessantes Verfahren, welches bisher als nichtinvasive Methode zur Tumorbehandlung auf Basis von ultraschallinduzierter Gewebeerwärmung und -zerstörung im medizinisch-therapeutischen Bereich eingesetzt wird. Die prinzipielle Eignung des Verfahrens zur Erwärmung von Kunststoffen ist nur in wenigen wissenschaftlichen Veröffentlichungen beschrieben. Als Fügeverfahren zum Bauteilschweißen von mehreren Millimetern dicken Kunststoffplatten wurde das Prinzip in den 1970er Jahren erprobt. Eine industrielle Nutzung ist jedoch nicht bekannt und der publizierte Stand der Technik ist weit von den Anforderungen des modernen Verarbeitungsmaschinenbaus entfernt. Daraus ergibt sich die Motivation zur Schaffung einer Wissensbasis für dieses Fügeverfahren und die Abschätzung dessen Potential unter verarbeitungstechnischen Maßstäben. Dabei fließen physikalische Grundlagen zur Akustik und Erkenntnisse zu den Wirkzusammenhängen in der Medizin ebenso wie verpackungstechnische Grundlagen ein. Die Ergebnisse der Arbeit stellen die Grundlage für weiterführende Untersuchungen zum stoffschlüssigen Fügen polymerer Packstoffe mittels hochintensivem fokussierten Ultraschall dar.
137

Physiological responses to concurrent resistance exercise and high-intensity interval training : implications for muscle hypertrophy

Pugh, Jamie K. January 2016 (has links)
No description available.
138

Applications des ultrasons focalisés de haute intensité au traitement du glaucome / High intensity focused ultrasound for the treatment of glaucoma

Aptel, Florent 08 December 2011 (has links)
Le glaucome est une pathologie fréquente principalement due à une élévation de la pression intraoculaire. La pression intraoculaire est le fruit d’un équilibre entre la production du liquide qui remplit la portion antérieure de l’œil - l’humeur aqueuse - et son élimination. Les traitements du glaucome peuvent donc agir selon deux mécanismes : la réduction de la production d’humeur aqueuse par la destruction partielle ou l’inhibition pharmacologique du corps ciliaire, structure responsable de la production de l’humeur aqueuse, ou la facilitation de l’évacuation de l’humeur aqueuse en dehors de l’oeil. De nombreuses méthodes physiques peuvent être utilisées pour détruire le corps ciliaire : lasers, cryothérapie, micro-ondes, etc. Néanmoins, toutes ces méthodes ont deux inconvénients majeurs qui limitent leur utilisation : elles sont peu sélectives de l’organe à traiter, entraînant souvent des dommages des structures adjacentes, et elles présentent une relation effet-dose très inconstante, empêchant de prévoir avec précision l’effet du traitement. L’objectif de ce travail de thèse est le développement d’un dispositif ultrasonore de coagulation du corps ciliaire circulaire, comprenant 6 transducteurs piézoélectriques en forme de segments de cylindre, et générant 6 lésions segmentaires s’inscrivant dans un anneau de diamètre similaire à celui formé par le corps ciliaire. Les expérimentations animales ont montré une nécrose de coagulation sélective des zones du corps ciliaire traitées par le dispositif. Le premier essai clinique a montré que cette méthode était bien tolérée et permettait une réduction importante, prédictible et maintenue dans le temps de la pression intraoculaire / Glaucoma is a common disease mainly due to an increase of the pressure inside the eye. Intraocular pressure is the result of a balance between the production of liquid that fills the anterior part of eye - aqueous humor - and its elimination. All treatments for glaucoma aim to reduce the intraocular pressure and can therefore have two mechanisms of action: reducing aqueous humor production by the partial destruction or medical inhibition of the ciliary body - anatomical structure responsible for the production of aqueous humor - or facilitating the evacuation of aqueous humor out of the eye. Several physical methods can be used to destroy the ciliary body: laser, cryotherapy, microwave, etc. However, all these methods have two major drawbacks limiting their use: they are non-selective of the organ to be treated, often resulting in damage to the adjacent structures, and they have an unpredictable dose-effect relationship, preventing to accurately predict the treatment effect. The objective of this thesis is the development of a circular ultrasonic device incorporating six transducers producing high-intensity focused ultrasound for a selective coagulation of the ciliary body. A circular device with 6 piezoelectric transducers having a geometry of a segment of a cylinder was used to generate six segmental lesions entering in a ring of diameter similar to that formed by the ciliary body. Animal experiments have shown a selective coagulation necrosis of the treated ciliary body. The first clinical trial in humans showed that this method was well tolerated and allowed a significant, predictable and sustained reduction of the intraocular pressure
139

Efeito agudo do exercício realizado em diferentes intensidades sobre a fome, hormônios relacionados ao apetite e ingestão alimentar em homens e mulheres / Acute effect of exercise intensity on hunger, hormones related appetite and food intake in men and women

Valéria Leme Gonçalves Panissa 18 September 2015 (has links)
A manutenção da saúde, depende, dentre outros aspectos, do controle da massa corporal, uma vez que a obesidade está associada ao desenvolvimento de doenças crônicas. Sendo assim, o exercício pode ser considerado uma ferramenta eficaz nesse controle. Contudo, está evidenciado que o exercício realizado em alta intensidade pode ocasionar maior redução da gordura corporal. Dentre as hipóteses sugeridas para explicar tal fenômeno, a supressão do apetite pós-exercício foi levantada, no entanto, o efeito da intensidade sobre o apetite ainda é incipiente. Além disso, mulheres podem ter maior resposta compensatória que homens. Portanto, o objetivo do estudo foi comparar o efeito da intensidade no controle agudo do apetite, energia ingerida absoluta e relativa (energia ingerida menos o gasto calórico do exercício), percepção de fome e das concentrações sanguíneas de grelina acilada, peptídeo YY3-36, insulina, cortisol, glicose, ácidos graxos, colesterol e triacilglicerol em homens e mulheres. Para isso, 11 homens e 9 mulheres eutróficos, foram submetidos a 6 sessões, sendo a primeira destinada à determinação da potência aeróbia máxima (PAM) em cicloergômetro, e a segunda para realização do exercício intermitente de alta intensidade realizado na máxima intensidade (all out), composto por 60 x 8s:12s (EIAI-A), para determinação do trabalho total, o qual foi utilizado para equalização das demais sessões: a) EIAI-A; b) exercício intermitente de alta intensidade (EIAI) - 60s:60s a 100% da PAM; c) exercício contínuo de intensidade moderada (ECMI) a 60% da PAM; d) sessão controle (sem exercício). Cada visita teve duração de 4h, sendo que os participantes chegaram em jejum e receberam um café da manhã padrão. O exercício foi realizado 1,5h pós-café da manhã, e uma alimentação ad libitum foi servida 4h pós-café da manhã. Coletas de sangue e da percepção de fome (escala analógica visual) foram realizadas em jejum e em 2, 2,5, 3,25 e 4h de experimento e calculada a área sob a curva (ASC) para cada uma dessas variáveis. A comparação das variáveis sanguíneas e da percepção de fome foi feita através de análise de variância a três fatores (condição, sexo e momento), e das variáveis envolvendo a ASC e a energia ingerida foi conduzida através de análise a dois fatores (condição e sexo), seguida do pós-teste de Bonferroni se observada diferença significativa (P<0,05). Não houve diferença para a energia ingerida absoluta, porém, a energia ingerida relativa foi maior no controle quando comparada ao EIAI-A, EIAI, e ao ECMI, sem diferenças entre os tipos de exercício e sexos. A ASC da percepção de fome foi menor somente nos exercícios realizados em alta intensidade comparado com o controle, independentemente do sexo. O PYY3-36 foi inferior nas mulheres em relação aos homens ao passo que o cortisol foi inferior nos homens comparado com as mulheres. Houve interação entre situação e momento de coleta para o cortisol e insulina sendo os valores mais elevados no EIAI-A que no controle às 2,5 horas de experimento para o cortisol e às 3,25h para insulina. Portanto, embora não tenha havido diferença na energia ingerida relativa entre os tipos de exercícios, àqueles realizados em maior intensidade foram capazes de promover efeitos mais pronunciados na supressão do apetite, independentemente do sexo / Maintaining one\'s health depends, among other things, on controlling body weight, since obesity is associated with the development of chronic diseases. Accordingly, exercise is an effective tool in this control. It has been demonstrated that exercise performed at a high intensity can cause greater reduction in body fat. Among the hypotheses put forward of this phenomenon is the suppression of appetite. However, the understanding of the effect of the intensity on appetite is still incipient. In addition, women may have a greater compensatory response than men. Therefore, the aim of the study was to compare the effect of intensity on absolute and relative (energy intake less caloric expenditure of the exercise) energy intake, hunger and blood concentrations of acylated ghrelin, PYY3-36, insulin, cortisol, glucose, fatty acids, cholesterol and triacylglycerol in men and women. Accordingly, 11 men and 9 women, all eutrophic, underwent six sessions. The first was designed to determine their maximum aerobic power (MAP) on a cycle ergometer, and the second involved performing high-intensity intermittent exercise at maximum intensity (all out) for 60 x 8s: 12s (HIIE-A) in order to determine the total work, which was used for the equalization of the other sessions: a) HIIE-A; b) high intensity intermittent exercise (HIIE) - 60s: 60s at 100% of MAP; c) steady-state exercise (SSE) at 60% of the MAP; d) a control session. Each session lasted a total of 4 hours. The participants arrived in fasting and received a standard breakfast upon arrival. The exercise session was performed 1.5 h after breakfast, and an ad libitum meal was served 4 hours post-breakfast. Blood sample collection and perception of hunger were collected when fasting and at 2, 2.5, 3.25 and 4 hours into the experiment and the area under the curve (AUC) for each of these variables was calculated. A comparison of the blood sample variables and rating of hunger was performed by analyzing the variance of three factors (condition, sex, and time) and the analysis of the variables involving the AUC and energy intake was conducted through examination of two factors (sex and condition) followed by a Bonferroni post-test if significant differences (P<0.05) were observed. There was no difference for the absolute energy intake, however, relative energy intake was higher in the control compared to HIIE-A, HIIE, and SSE, with no differences between the types of exercise and sex. The AUC of hunger was lower in exercises performed at high intensity when compared to the control, regardless of sex. There was interaction between condition and time for cortisol and insulin, with higher levels in the HIIE-A than in the control at 2.5 hours for cortisol and 3.25 hours for insulin. Therefore, although there were no differences in energy intake relative to the types of exercises, those performed at a higher intensity promoted more pronounced effects on appetite suppression, regardless of sex
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O exercício intermitente modula o metabolismo lipídico em ratos: o fígado como órgão gerenciador / Intermittent exercise modulates the lipid metabolism in rats: the as the manager

Robson Eder 02 March 2010 (has links)
A associação de uma série de influências ambientais como dietas com excesso de gordura ou falta de atividade física regular (sedentarismo) são importantes fatores que podem levar ao desenvolvimento da obesidade e dislipidemias. Portanto, a prática de atividade física regular, caracterizada pelo treinamento, mostra-se atualmente como parte de estratégias para combater problemas como dislipidemias. Sabe-se que o aumento do gasto calórico e a melhora no desempenho podem ser atingidos com treinamentos de endurance ou intermitentes, uma vez que ambos levam à alterações fisiológicas e metabólicas semelhantes. O treinamento intermitente é caracterizado pela execução de repetidas sessões de curtos ou longos períodos, preferencialmente de alta intensidade (aproximadamente 100% do VO2máx.), intercaladas por pausas ou períodos de menor intensidade, visando a recuperação do indivíduo. Dada a importância do fígado no metabolismo lipídico em repouso e no exercício foi nosso interesse avaliarmos o comportamento do fígado frente a oito semanas de treinamento intermitente de alta intensidade e comparar tais alterações às promovidas pelo treinamento de endurance em ratos, com especial atenção a síntese e secreção de VLDL. Os animais foram divididos em três grupos: sedentário (SD), treinamento contínuo (TC) e treinamento intermitente de alta intensidade (TI). Os dois protocolos de treinamento resultaram em menor ganho de peso em comparação com o grupo SD. Ainda o grupo TI apresentou maior secreção de VLDL em comparação aos grupos TC e SD. Além disso, a expressão gênica da MTP, proteína chave na montagem da VLDL e da LPL muscular responsável por catalisar a liberação de TAG da VLDL para captação pelo músculo esquelético demonstrou aumento no grupo TI em comparação ao SD. Tais resultados inferem que o treinamento intermitente modulou o transporte de TAG para a periferia e contribui para um efeito hipotrigliceridêmico após o exercício de alta intensidade / The combination of environmental influence, including high fat diets and lack of regular physical activity (sedentary lifestyle) are important factors leading to the development of obesity and dyslipidemias. Regular practice of physical activity, characterized by training, appears as important strategy to reduce such problems. Increased caloric expenditure and improvement of physical performance can be reached with endurance or intermittent training since both lead to similar physiological and metabolic adaptations. Intermittent training is characterized by the execution of repeated bouts of physical effort (high intensity, approximately 100% of VO2max.) Due to the importance of the liver in lipid metabolism during rest and exercise, we examined the adaptations of organ to 8 weeks of high intensity intermittent training, compared with the effect of endurance exercise with special attention to VLDL synthesis and secretion. The animals were randomized into three groups: sedentary (SD), continuous training (TC) and intermittent training (TI). Both training protocols resulted in reduced weight body gain compared with SD, although IT presents higher VLDL secretion, compared with TC and SD. In addition, gene expression of MTP, a key protein in the assembly of VLDL and LPL muscle responsible for catalyzing the release of TAG for VLDL uptake by skeletal muscle, showed an increase in TI compared to SD. These results suggest that intermittent training modulated the transport of TAG to the periphery and contributed to an hypotriglyceridemic effect caused by high intensity exercise

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