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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.
71

Evolução temporal do controle autonômico e respostas cardiovasculares associadas em SHR jovens submetidos ao treinamento aérobio. / Temporal evolution of autonomic control and cardiovascular responses associated in young SHR submitted of aerobic training.

Ruggeri, Adriana 23 November 2016 (has links)
É hipótese que (treinamento) T iniciado na fase pré-hipertensiva possa reduzir a atividade simpática e aumentar a vagal ao coração, melhorando a regulação autonômica nos SHR. Investigamos em SHR e WKY jovens (29 dias) os efeitos do T sobre parâmetros hemodinâmicos, funcionamento dos barorreceptores arteriais, tônus simpático e vagal ao coração e variabilidades, e expressão de neurônios pré-ganglionares vagais (Colina Acetil Transferase, ChAT) nos núcleos dorsal motor do vago (DMV) e ambíguo (NA). Ratos T ou sedentários (S) foram canulados nas semanas 0, 1, 2, 4 e 8, para registros funcionais e remoção dos encéfalos para a quantificação (peroxidade e estereologia). A participação dos aferentes periféricos na modulação dos efeitos do T foi avaliada com a desnervação sinoaórtica (SAD). Os efeitos do T são modulados por baro- e quimiorreceptores. O T precoce corrige a disfunção baroreflexa, reduz a hipertonia simpática, mantém parcialmente a tonicidade de neurônios colinérgicos, aumentando a modulação vagal ao coração e melhorando controle autonômico da circulação. / We hypothesized that aerobic training (T) starting at the pre-hypertensive phase reduces not only the sympathetic activity, but increases vagal outflow to the heart, thus improving autonomic cardiovascular control. We investigated in young SHR and WKY the T-induced effects on hemodynamic parameters, activation of arterial baroreceptor, sympathetic and vagal tone to the heart, and the expression of pre-ganglionic parasympathetic neurons (Choline acetyl transferase, ChAT) in the dorsal motor nucleus of the vagus (DMV) and nucleus ambiguous (NA). Rats (29 days) were T or sedentary (S) and cannulated at weeks 0, 1, 2, 4 and 8. After functional recordings, brains were harvested for quantification of neurons (peroxidase and stereology). The peripheral afferents was evaluated in sinoaortic denervation (SAD). SAD abrogated the improvement of baroreflex control and resting bradycardia in intact SHR-T. T-induced effects were modulated by arterial baro- and chemoreceptors. When started at the pre-hypertensive phase, T corrects baroreflex dysfunction, reduces sympathetic hyperactivity, maintain the tonicity of pre-ganglionic cholinergic neurons thus increasing vagal outflow to the heart and allowing a better autonomic control of the circulation.
72

Efeitos sequenciais do treinamento aeróbio sobre o sistema renina-angiotensina em núcleos autonômicos de ratos normotensos e hipertensos. / Sequential effects of aerobic training on the renin-angiotensin system in autonomic nuclei of normotensive and hipertensive rats.

Chaar, Laiali Jurdi El 23 January 2012 (has links)
Treinamento aeróbio (T) reduz o elevado RNAm de angiotensinogênio (AGT), no NTS de SHR. Este trabalho investiga a sequência temporal dos efeitos do T sobre a pressão arterial, freqüência cardíaca, RNAm e proteína de AGT e AT1 no PVN, NTS e RVL. WKY e SHR, submetidos a T de baixa intensidade por 0, 1, 2, 4, 8 ou 12 semanas, tiveram a PA e FC basais registradas e após o sacrifício determinou-se o RNAm (RT-PCR) e imunofluorescência para AGT ou AT1 e NeuN. SHR (vs WKY) apresentaram PA (174±2 vs 123±2 mmHg) e FC elevadas e maior RNAm de AT1 no NTS(+67%). T reduziu a PA em S de T4 à T12 e FC em S em T4 e WKY em T8. Nos SHR, T reduziu o RNAm de AGT no PVN (-34% em T2) e NTS (-30% em T4), e de AT1 apenas em T12 (-56% e -39%, PVN e NTS). Nos WKY, T reduziu o RNAm de AGT(-49%) e AT1(-58%) no RVL a partir de T8. A imunofluorescência localizou estas proteínas, confirmando as alterações pelo T. Estes dados indicam que a queda de PA e FC são progressivas e mais precoces em SHR que em WKY e acompanhadas por redução de AGT no PVN e NTS dos S e redução de AGT e AT1 no RVL dos WKY. / The aerobic training (T) for 12 weeks was effective in reducing the mRNA of angiotensinogen(AGT) in NTS of SHR. We evaluate in SHR and WKY time-course changes of T on blood pressure, heart rate, AGT and AT1 mRNA and protein (PVN, NTS and RVL). WKY and SHR were T for 0,1,2,4,8 or 12 weeks, the baseline BP and HR were recorded and mRNA(RT-PCR) and Immunofluorescence for AGT, AT1 and NeuN were made. SHR(vs. WKY) had high BP(174±2 vs 123±2 mmHg), HR and mRNA of AT1 in the NTS(+67%). T reduced the BP only in SHR(-6.5% from T4 to T12) and HR in SHR in T4 and WKY in T8. In the SHR, T reduced the AGT mRNA within the PVN (-34% in T2) and NTS (-30% in T4), and AT1 mRNA only in T12 in PVN(-56%) and NTS(-39%). In WKY, T decreased of both AGT(-49%) and AT1(-58%) mRNA in the RVL at T8. Immunofluorescence localized these proteins, confirming the mRNA content changes induced by T. Our data indicate that the fall of BP and HR are progressive and appear earlier in SHR than in WKY and are accompanied by reduced AGT in the PVN and NTS of the SHR and reduced AGT and AT1 in RVL of WKY.
73

Effect of Obesity and Exercise on the Expression of the Novel Myokines, Myonectin and Fibronectin Type III Domain Containing 5

Peterson, Jonathan M., Mart, Ryan, Bond, Cherie E. 30 September 2014 (has links)
Metabolic dysfunction in skeletal muscle is a major contributor to the development of type 2 diabetes. Endurance exercise training has long been established as an effective means to directly restore skeletal muscle glucose and lipid uptake and metabolism. However, in addition to the direct effects of skeletal muscle on glucose and lipids, there is renewed interest in the ability of skeletal muscle to coordinate metabolic activity of other tissues, such as adipose tissue and liver. The purpose of this study was to examine the effects of endurance exercise on the expression level of two novel muscle-derived secreted factors, or myokines, Myonectin and Fibronectin type III domain containing 5 (FNDC5), the precursor for Irisin. Methods. We performed immunoblot analysis and quantitative real-time PCR analysis of Myonectin and FNDC5 in the diaphragm muscles of obese Zucker rat (OZR) and lean Zucker rat (LZR) with 9 weeks of aerobic training on a motorized treadmill. Results. We show that myonectin gene expression is increased in the OZR model of obesity and decreases with exercise in both lean and obese Zucker rats. Conversely, myonectin protein concentration was elevated with exercise. Similarly, FNDC5 mRNA levels are significantly higher in the OZR, however exercise training had no effect on the expression level of FNDC5 in either the LZR or OZR. We did not observe any difference in muscle protein content of Irisin with obesity or exercise. Conclusion. Our data shows that exercise training does not increase either FNDC5 or myonectin gene expression, indicating that increased transcriptional regulation of these myokines is not induced by exercise. However, our data also indicates a yet to be explored disconnect between myonectin gene expression and protein content. Further, this report highlights the importance of verifying reference genes when completing gene expression analysis. We found that many commonly used reference genes varied significantly by obesity and/or exercise and would have skewed the results of this study if used to normalize gene expression data. The unstable reference genes include: beta-Actin, beta-2-microglobulin, Non-POU domain containing, octamer-binding, Peptidylprolyl isomerase H, 18S ribosomal RNA, TATA box binding protein and Transferrin receptor.
74

The effects of carbohydrate-protein supplementation on endurance exercise performance, recovery, and training adaptation

Stegall, Lisa Ferguson 07 February 2011 (has links)
Recent research suggests that adding protein (PRO) to a carbohydrate (CHO) supplement can have substantial benefits for endurance exercise performance and recovery beyond that of CHO alone. CHO+PRO supplements are often commercially available formulations consisting of carbohydrates (dextrose, maltodextrin) and whey protein. The effects of a supplement containing moderate protein and a low-CHO mixture on endurance performance has not been investigated. Also, the effects of CHO+PRO supplementation in the form of a natural food, flavored milk, on measures of recovery from acute endurance exercise, as well as on chronic aerobic exercise training adaptations, have not been characterized. Therefore, in this series of four studies, the effects of CHO+PRO supplementation on the following areas of endurance exercise performance, recovery, and adaptation are investigated: acute endurance exercise performance, inflammatory and muscle damage markers, muscle glycogen resynthesis, activation of signaling proteins involved in the initiation of protein synthesis and degradation, subsequent endurance exercise performance, and chronic aerobic training adaptations (maximal oxygen consumption, oxidative enzyme activity, body composition, immune cell levels, and inflammatory markers). Study 1 demonstrated that a supplement containing a low-CHO mixture plus moderate protein significantly improved aerobic endurance when cycling at or below the ventilatory threshold, despite containing 50% less CHO and 30% fewer calories relative to a higher CHO beverage. Study 2 demonstrated that CHO+PRO supplementation in the form of chocolate milk (CM) is an effective post-exercise supplement that can improve subsequent performance and provide a greater intracellular signaling stimulus for protein synthesis compared to CHO and placebo. Study 3 found that post-exercise CM supplementation during 4.5 wks of aerobic exercise training improves the magnitude of cardiovascular adaptations more effectively than isocaloric CHO or placebo, while the fourth study demonstrated that post-exercise CM supplementation during 4.5 wks of aerobic training improves body composition more effectively than isocaloric CHO or placebo. The fourth study also demonstrated that 4.5 wks of training does not appear to perturb resting immune cell concentrations or markers of inflammation and muscle damage. Taken together, the results of this research series suggest that CHO+PRO supplementation extends endurance performance, improves recovery, and increases training adaptations more effectively than CHO or placebo. / text
75

Adaptations cardiaques à l’exercice aigu, chronique et épuisant de longue durée : mise en évidence du rôle clé du mécanisme de torsion - détorsion dans le remplissage ventriculaire gauche / Cardiac adaptations to acute, chronic and streneous exercise : key role of twisting - untwisting mecanism in left ventricular filling

Doucende, Grégory 23 November 2010 (has links)
Lors de la systole, le ventricule gauche (VG) se déforme suite à la contraction des cardiomyocytes. De part l’orientation en spirale des fibres myocardiques, ces déformations incluent un mouvement de torsion, la base et l’apex du VG tournant dans des sens opposés. L’emmagasinement d’énergie élastique par ce mécanisme et surtout sa restitution très précoce en début de diastole jouent un rôle clé dans le remplissage ventriculaire gauche. Les objectifs de ce travail ont été d’étudier les adaptations mécaniques ventriculaires gauche en se focalisant sur le rôle de la torsion 1) lors d’un exercice d’intensité croissante chez le sujet sédentaire jeune, 2) suite à l’entrainement aérobie au repos et lors d’un exercice d’intensité croissante et, 3) concomitantes aux dysfonctions cardiaques observées après un exercice épuisant de longue durée. Pour cela, nous avons effectué des échocardiographies au repos et/ou lors d’épreuves d’effort d’intensité croissante en incluant l’utilisation d’un nouvel outil échocardiographique basé sur le "speckle tracking" (STE). Nos résultats soulignent le rôle clé de la torsion dans le couplage systole – diastole à l’effort. De plus, nos résultats montrent une modification des adaptations mécaniques ventriculaires gauche à l’effort en parallèle à l’amélioration de la fonction diastolique chez les sportifs entrainés en endurance aérobie. Enfin, la dysfonction ventriculaire gauche transitoire observée après un exercice épuisant de longue durée est caractérisée par une diminution et un décalage dans le temps de la torsion, limitant probablement la diminution précoce des pressions intraventriculaires gauche et donc le remplissage. L’ensemble de ces résultats mettent en évidence, d’une part, l’intérêt de l’évaluation par STE de la mécanique ventriculaire gauche au repos et à l’effort, et d’autre part le rôle clé du mécanisme de torsion – détorsion dans l’explication de fonctions diastoliques améliorées ou altérées / During systole, contraction of cardiomyocytes induces left ventricular (LV) strains. Moreover, the helical orientation of myofibers induces LV torsion consequently to LV basal and apical rotations. LV torsion stores energy in elastic component that is released very early in diastole and constitutes a key factor of LV filling. The aims of this thesis were to characterize LV mechanicals adaptations focussing on the role of LV torsion 1) during a progressive exercise test in healthy sedentary subjects, 2) induced by aerobic training at rest and during a progressive exercise test and, 3) concomitant with cardiac dysfunctions after prolonged and strenuous exercise. We used a novel echocardiographic tool, based on Speckle Tracking (STE), in order to evaluate LV function at rest and/or during a progressive exercise test. Our results underlined the key role of LV torsion in systolic – diastolic coupling during exercise. Moreover, our results showed an alteration of LV mechanical adaptation paralleling the enhancement of diastolic function during effort in aerobic trained subjects. At last, transient LV dysfunction after prolonged and strenuous exercise was associated with decreased and delayed LV torsion, probably limiting the early drop of LV intraventricular pressures and thus LV filling. All together, these results underlined the usefulness to evaluate LV mechanics at rest and during effort by STE, and point out the key role of twisting – untwisting mechanism in improved or depressed LV diastolic function
76

Evolução temporal da pressão arterial e de alterações vasculares em SHR jovens durante o estabelecimento da hipertensão: o efeito do treinamento. / Time-course changes of blood pressure and vascular remodeling in young shr during the stablishment of hypertension: effects of low intensity aerobic training.

Raul Henrique Oliveira Pinheiro 02 September 2015 (has links)
Estudos na fase crônica da hipertensão comprovam a eficácia do treinamento aeróbio (T) em reduzir parcialmente a pressão arterial (PA), no qual correlacionavam-se com o remodelamento vascular. Pouco se sabe sobre o potencial efeito benéfico do T iniciado em fase pré-hipertensiva. Os objetivos foram analisar em SHR jovens (4 semanas) e seus controles WKY os efeitos sequenciais do T sobre níveis de PA, alterações vasculares, conteúdo de colágeno total, associando-as à modulação neural. Animais em fase pré-hipertensiva realizaram T de baixa intensidade (50-60%) ou sedentarismo por 8 semanas. Foram avaliados os parâmetros funcionais e seus componentes espectrais, alterações estruturais ocorridas em artérias (femoral e renal), arteríolas (músculo sóleo e temporal) e com conteúdo de colágeno. O T reduziu a PAM no SHR na 4ª e 8ª semana, provocou bradicardia de repouso em ambos os grupos na 8ª, melhorou a variabilidade da FC (WKY e SHR) e impediu o aumento da variabilidade da PAS nos SHR. Hipertensão provocou aumento da razão parede/luz e conteúdo de colágeno em ambas as artérias, T impediu esse aumento na artéria femoral, efeito não foi observado na artéria renal. T impediu a queda da razão parede/luz em arteríolas do músculo sóleo sem efeitos no músculo sóleo. / Studies in the chronic phase of hypertension prove the effectiveness of aerobic training (T) in partially reduce blood pressure (BP), which correlated with vascular remodeling. Little is known about the potential beneficial effect of T started in pre-hypertensive stage. The objectives were to analyze in young SHR (4 weeks) and their WKY controls the sequential effects of T on BP levels, vascular changes, total collagen content, linking them to the neural modulation. Animals in the pre-hypertension stage T made of low intensity (50-60%) or inactivity for 8 weeks. We evaluated the functional parameters and their spectral components, structural changes in arteries (femoral and renal), arterioles (soleus muscle and temporal) and collagen content. OT reduced MAP in SHR at 4 and 8 weeks, caused bradycardia standby in both groups in 8th improved HR variability (WKY and SHR) and prevent the increase of SBP variability in SHR. Hypertension caused ratio increase / wall light and collagen content in both arteries, t prevented this increase in femoral artery, an effect was not observed in the renal artery. T prevented the fall of reason / wall light in arterioles of the soleus muscle without effects in the soleus muscle.
77

Efeito de quatro semanas de treinamento com oclusão de fluxo sobre os índices de aptidão aeróbia, composição corporal e força muscular / Effect of four weeks of blood flow training in the aerobics, strength and body composition variants

Corvino, Rogério Bulhões 23 February 2012 (has links)
Made available in DSpace on 2016-12-06T17:06:47Z (GMT). No. of bitstreams: 1 Rogerio Bulhoes Corvino.pdf: 873037 bytes, checksum: 3dd80890c4711166c207e26044d827a4 (MD5) Previous issue date: 2012-02-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this research was analyze the effect of a training realized in cycle ergometer with leg blood flow occlusion on aerobic fitness, muscular strength and body composition parameters. Participate in this study 11 apparently healthy individuals of both genders, with ages between 18 and 30 years old. Subjects performed before and after four weeks of training these tests: 1) Progressive tests to the exhaustion to determine the anaerobic threshold (LAn), maximal oxygen uptake (VO2máx), and peak power (PMAX). 2) Constant load tests until volitional exhaustion (Tlim) in the intensities of 95% and 110% of PMAX to determine the on-kinetics of VO2 (Tau) in moderate (30%PMAX) and severe (110%PMAX) domains, Critical Power (CP), 3) Tests to determine the maximum isometric force of the quadriceps muscle. 4) Measurement of anthropometric variables. During a period of 4 weeks, the experimental group (N=11) performed a total of 12 sessions of leg blood flow occlusion in cycle ergometer at a low intensity (30%PMAX) The parameters Lan (BEFORE 160±52; AFTER 177±57 W), PMAX (BEFORE 246 ±48; AFTER 269±57 W), Tau30% (BEFORE 22,9±8; AFTER 18,4±5 s), Tau110% (BEFORE 43,3±19; AFTER 31,9±12 s), PC (BEFORE 180±52; AFTER 199±46 W), and maximal isometric strength (BEFORE 289±62; AFTER 318±56 N.m-1) were significantly increased after training. For the VO2max (BEFORE 1296±187; AFTER 3329±732 ml/min), VO2 at 30%PMAX (BEFORE 1296±187; AFTER 1317±220 ml/min) and anthropometric variables did not show any significantly different after training. We conclude that four weeks of leg blood flow occlusion training in cycle ergometer was able to generate changes in aerobics and neuromuscular parameters in active subjects in the similar proportions to traditional training methods. Moreover, the no effect on VO2máx whit improvements seen on the aerobic capacity and VO2 kinetcs suggest that major adaptations caused by this type of training should have been more peripheral than central factors / O objetivo deste estudo foi analisar o efeito do treinamento realizado em cicloergômetro com oclusão parcial de fluxo sanguíneo das pernas sobre parâmetros relacionados à aptidão aeróbia, força muscular e composição corporal. Participaram deste estudo 11 indivíduos aparentemente saudáveis de ambos os gêneros, com idades entre 18 e 30 anos. Os indivíduos realizaram, antes e após um período de quatro semanas de treinamento: 1) testes progressivos até a exaustão para a determinação do limiar anaeróbio (LAn), consumo máximo de oxigênio (VO2max), e potência máxima (PMAX) em cicloergômetro. 2) testes de carga constante com 6 min de duração à 30% da PMAX e até a exaustão voluntária (Tlim) à 95 e 110% da PMAX para determinação da cinética do VO2 (Tau) em intensidade moderada (30%PMAX) e severa (110%PMAX), e Potência Crítica (PC) através da relação linear entre a potência e seu respectivo Tlim (95 e 110%PMAX). 3) testes para determinação da força máxima isométrica dos músculos extensores do joelho. 4) Mensuração das variáveis antropométricas. Durante o período de 4 semanas, o grupo experimental (n = 11) realizou um total de 12 sessões de treinamento aeróbio de baixa intensidade (30%PMAX) com oclusão de fluxo sanguíneo em ambas as pernas. Os parâmetros LAn (PRÉ 160±52; PÓS 177±57 W), PMAX (PRÉ 246 ±48; PÓS 269±57 W), Tau30% (PRÉ 22,9±8; PÓS 18,4±5 s), Tau110% (PRÉ 43,3±19; PÓS 31,9±12 s), PC (PRÉ 180±52; PÓS 199±46 W), e força máxima isométrica (PRÉ 289±62; PÓS 318±56 N.m-1) foram significativamente aumentados após o treinamento. Para os valores de VO2max (PRÉ 3242±707 ; PÓS 3329±732 ml/min), e VO2 à 30%PMAX (PRÉ 1296±187; PÓS 1317±220 ml/min) e variáveis antropométricas não foram observadas diferenças significativas após o treinamento. Podemos concluir que quatro semanas de treinamento em bicicleta ergométrica com oclusão de fluxo foi capaz de gerar adaptações em parâmetros aeróbios e neuromusculares em sujeitos ativos em proporções similares a outros métodos tradicionais de treinamento. Além disso, a ausência de efeito sobre o VO2max e as melhoras observadas sobre a capacidade aeróbia e cinética do VO2 sugerem que as principais adaptações causadas por esse tipo de treinamento devem ter sido mais periféricas do que centrais.
78

Treino de sprint em ciclo ergômetro promove aumento nos níveis de força similar ao treinamento de força no leg press em homens treinados / Sprint training in cycle ergometer promotes increased strength levels similar to leg press strength training in trained men.

Silva, Marcelo Henrique 12 June 2018 (has links)
Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2018-09-04T15:37:43Z No. of bitstreams: 2 Dissertação - Marcelo Henrique Silva - 2018.pdf: 1512262 bytes, checksum: 0c1d4b041db8f6a09d324c78b4dd0338 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-05T11:18:06Z (GMT) No. of bitstreams: 2 Dissertação - Marcelo Henrique Silva - 2018.pdf: 1512262 bytes, checksum: 0c1d4b041db8f6a09d324c78b4dd0338 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-05T11:18:06Z (GMT). No. of bitstreams: 2 Dissertação - Marcelo Henrique Silva - 2018.pdf: 1512262 bytes, checksum: 0c1d4b041db8f6a09d324c78b4dd0338 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-06-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Introductions: Traditionally, stimuli for increased strength and cardiorespiratory fitness are prescribed separately based on the different characteristics of the modalities and the adaptations that each promotes. This separation has been questioned by recent studies that suggest that the intensity with which the exercise is performed seems to generate greater influence than the equipment involved. Based on this assumption, the adaptations promoted by physical exercise should be related to the effort and not to the modality in question. Thus, the objective of the present study was to compare the changes in muscle strength and cardiorespiratory fitness promoted by strength and aerobic training, with similar duration. Methods: 25 men (28.9 ± 5.6 years) with experience in strength training (6.6 ± 5.6 years of training) performed a cardiorespiratory effort test and 10 maximal repetitions in knee extensor. After the tests, the participants were randomly divided into a cycle (4 sets of 30 "sprints on stationary bicycle) and Leg Press (4 sets of 10-12 maximum repetitions), three times a week with three minutes and a half interval between sets for 5 weeks. After the training period, the tests were repeated. Results: The peak oxygen consumption ( 2peak) increased 10.2% (p = 0.012) in the BIC group, a significantly higher result when compared to the LP (p = 0.023). Regarding BIC and LP strength levels, there were increases of 17.7 and 22.9%, respectively (p <0.05), with no differences between groups (p = 0.614). Conclusion: The results of the present study suggest that performing sprint in cycle ergometer is more efficient than strength training in leg press because it presented similar increase in strength levels besides a significantly higher increase in cardiorespiratory fitness. / Introdução: Tradicionalmente os estímulos para aumento de força e de condicionamento cardiorrespiratório são prescritos separadamente com base nas diferentes características das modalidades e nas adaptações que cada uma promove. Essa separação vem sendo questionada por estudos recentes que sugerem que a intensidade com que o exercício é realizado parece gerar maior influência que os equipamentos envolvidos. Com base nessa suposição, as adaptações promovidas pelo exercício físico devem estar relacionadas ao esforço e não à modalidade em questão. Com isso o objetivo do presente estudo foi comparar as alterações na força muscular e no condicionamento cardiorrespiratório promovidos pelo treinamento de força e aeróbio, com duração similar. Métodos: 25 homens (28,9 ± 5,6 anos) com experiência em treinamento de força (6,6 ± 5,6 anos de treino) realizaram teste de esforço cardiorrespiratório e de 10 repetições máximas em cadeira extensora. Após os testes, os participantes foram aleatoriamente divididos em Bicicleta estacionária (BIC) (4 séries de sprints de 30”) e Leg press (LP) (4 séries de 10-12 repetições máximas), três vezes por semana com intervalo de três minutos e meio entre as séries, durante 5 semanas. Após o período de treino, os testes foram repetidos. Resultados: O consumo pico de oxigênio ( 2pico) aumentou 10,2% (p = 0,012) no grupo BIC, resultado significativamente superior quando comparado ao LP (p = 0,023). Com relação aos níveis de força BIC e LP apresentaram aumentos de 17,7 e 22,9% respectivamente (p < 0,05) sem diferenças entre os grupos (p = 0,614). Conclusão: Os resultados do presente estudo sugerem que a realização de sprint em ciclo ergômetro apresentou aumento similar nos níveis de força em comparação ao leg press, além de aumento significativamente superior no condicionamento cardiorrespiratório.
79

Comparação dos indicadores funcionais e bioquimicos em homens de meia-idade submetidos a treinamento aerobio e corredores de longa distancia / Comparison of functional and biochemical indicators in middle aged men undergoing aerobic training and long distance runners

Salgado, José Vitor Vieira, 1977 14 August 2018 (has links)
Orientador: Mara Patricia Traina Chacon Mikahil / Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Educação Fisica / Made available in DSpace on 2018-08-14T05:19:49Z (GMT). No. of bitstreams: 1 Salgado_JoseVitorVieira_M.pdf: 867713 bytes, checksum: 6908f05e1d80d8d4a637179e624366e2 (MD5) Previous issue date: 2009 / Resumo: O avançar da idade aliado à inatividade física contribuem para o surgimento de uma série de doenças metabólicas dentre as quais se destacam a hipertensão arterial, obesidade, síndrome da resistência à insulina e dislipidemia, levando a um quadro de síndrome metabólica (SM) aumentando o risco de desenvolvimento de diabetes mellitus e doenças cardiovasculares. O presente estudo objetivou investigar se períodos curtos de intervenção com treinamento aeróbio de baixa a moderada intensidades podem promover alterações nos marcadores de risco de doenças cardiovasculares em homens de meia-idade. Além disso, procurou comparar essas possíveis alterações com indivíduos de mesma faixa etária praticantes de treinamento aeróbio regular há alguns anos (corredores de longa distância). Compuseram a amostra dois grupos de indivíduos do sexo masculino de meia idade, sendo que um dos grupos (n=15, 46,45±4,50 anos, 173,59±7.52 cm) submetido a um treinamento aeróbio com intensidades entre 60% e 80% do VO2pico durante 16 semanas com 3 sessões semanais e avaliado nos dois momentos distintos: chamados de pré treinamento aeróbio (PRÉ-TA) e pós treinamento aeróbio (PÓS-TA): massa corporal total 80,77±8,67kg e PÓS-TA: massa corporal total 78,83±9,01kg. Um segundo grupo estudado foi o de corredores de longa distância (C) (n=21, 47,43± 5,77 anos, massa corporal total 66,97±10,56 kg, 171,05±7,47 cm), com um tempo médio de treinamento 15,38 ± 8,94 anos percorrendo semanalmente 62,95 ± 32,04 km e com tempo médio de performance para 10km de 45'36" ± 6'32". Foi avaliado diretamente o consumo máximo de oxigênio (VO2pico), composição corporal, perfil lipídio, PCR, hemoglobina glicada, glicose de jejum, insulina basal; a resistência à insulina foi estimada por meio do método Homeostasis Model Assessment (HOMA-IR). A análise estatística foi realizada intergrupos e intragrupos adotando um valor de p<0,05. Foi observada diferença significante entre o grupo PRÉ-TA e PÓS-TA, com redução dos valores para as variáveis: massa corporal total (p=0,011), IMC (p=0,011), % de gordura (p=0,023), massa gorda (p=0,012), circunferência de cintura (p=0,001), colesterol total (p=0,009), LDL (p=0,038), insulina basal (p=0,036) e hemoglobina glicada (p=0,031) e aumento no consumo máximo de oxigênio (p=0,000). Contudo, para a massa magra, HDL, triglicérides, glicemia, HOMA e PCR não foram observadas diferenças estatísticas significantes. Quando comparados PÓS-TA e corredores somente não foram observadas diferenças estatísticas para a MM, colesterol total, LDL, triglicérides, glicemia e PCR, com menores valores para o grupo de corredores com exceção do maior VO2pico e HDL. Indivíduos de meiaidade apresentaram alterações positivas nos marcadores de risco de doenças cardiovasculares após a realização de apenas 16 semanas de treinamento aeróbio. No entanto, indivíduos que realizam TA durante anos, em intensidades superiores de treino demonstraram ter benefícios ainda maiores decorrentes do exercício físico, evidenciando o importante papel do exercício físico, em menor ou maior quantidade e intensidade, como sinalizador do controle de fatores de risco para o desenvolvimento de doenças associadas à síndrome metabólica / Abstract: The advancement of age combined with physical inactivity contribute to the emergence of a number of metabolic diseases among which are included; arterial hypertension, obesity, syndrome of insulin resistance and dyslipidemia. These could lead to a metabolic syndrome (MS) and increase the risks of developing diabetes and cardiovascular diseases. Thus, this study aims at investigating whether short periods of intervention with aerobic training of low to moderate intensities can promote changes in markers of risks of cardiovascular diseases in middle-aged men. Furthermore, we try to compare these changes with individuals of the same age who have been practitioners of regular aerobic training for several years (long-distance runners). The sample was composed of two groups of males of middle age, with one group (n = 15) 46,45 ± 4,50 years, 173,59 ± 7,52 cm subjected to an aerobic training with intensities between 60% and 80% of VO2peak for 16 weeks with 3 sessions per week and assessed in two distinct moments: pre-aerobic training (PRE-TA) and post-aerobic training (POST-TA). The total body mass for the PRE-TA sample populations is 80,77 ± 8,67 kg and that for POST-TA is 78,83 ± 9,01 kg. A second group studied was the long-distance runners (C) (n = 21), 47,43 ± 5,77 years, total body mass 66,97 ± 10,56 kg, 171,05 ± 7,47 cm, with an average of 15,38 ± 8,94 years of weekly training across an estimated distance of 62,95 ± 32,04 kilometers with an average time of performance for 10km of 45'36"± 6'32". The study directly assessed the maximum oxygen uptake (VO2peak.), body composition, lipid profile, CRP, glycated hemoglobin, fasting glucose, basal insulin and insulin resistance which was estimated using the Homeostasis Model Assessment method (HOMA-IR). Statistical analysis was performed between groups and within groups, and adopted a value of 0,05. A significant difference was observed between the group PRE and POST-TA-TA, with reduction of the values for the variables: total body mass (p=0,011), BMI (p=0,011),% fat (p=0,023), fat mass (p=0,012), waist circumference (p=0,001), total cholesterol (p=0,009), LDL (p=0,038), basal insulin (p=0,036) and glycated hemoglobin (p=0,031) and increase in the maximum oxygen (p=0,000). However, for lean mass, HDL, triglycerides, blood glucose, HOMA and CRP were not statistically significant difference. When compared POST-TA and runners not only statistical differences were observed for the MM, total cholesterol, LDL, triglycerides, glucose and CRP, with lower values for the group of runners with the exception of higher VO2peak and HDL. Middle-aged subjects showed positive changes in markers of risk of cardiovascular disease after the completion of only 16 weeks of aerobic training. However, individuals who perform TA for years in higher training intensities have demonstrated benefits of exercise even greater. These data indicate the important role of physical exercise, to a lesser or greater quantity and intensity, as flags of the control of risk factors for the development of diseases associated with metabolic syndrome. / Mestrado / Ciencia do Desporto / Mestre em Educação Física
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Efeitos sequenciais do treinamento aeróbio sobre o sistema renina-angiotensina em núcleos autonômicos de ratos normotensos e hipertensos. / Sequential effects of aerobic training on the renin-angiotensin system in autonomic nuclei of normotensive and hipertensive rats.

Laiali Jurdi El Chaar 23 January 2012 (has links)
Treinamento aeróbio (T) reduz o elevado RNAm de angiotensinogênio (AGT), no NTS de SHR. Este trabalho investiga a sequência temporal dos efeitos do T sobre a pressão arterial, freqüência cardíaca, RNAm e proteína de AGT e AT1 no PVN, NTS e RVL. WKY e SHR, submetidos a T de baixa intensidade por 0, 1, 2, 4, 8 ou 12 semanas, tiveram a PA e FC basais registradas e após o sacrifício determinou-se o RNAm (RT-PCR) e imunofluorescência para AGT ou AT1 e NeuN. SHR (vs WKY) apresentaram PA (174±2 vs 123±2 mmHg) e FC elevadas e maior RNAm de AT1 no NTS(+67%). T reduziu a PA em S de T4 à T12 e FC em S em T4 e WKY em T8. Nos SHR, T reduziu o RNAm de AGT no PVN (-34% em T2) e NTS (-30% em T4), e de AT1 apenas em T12 (-56% e -39%, PVN e NTS). Nos WKY, T reduziu o RNAm de AGT(-49%) e AT1(-58%) no RVL a partir de T8. A imunofluorescência localizou estas proteínas, confirmando as alterações pelo T. Estes dados indicam que a queda de PA e FC são progressivas e mais precoces em SHR que em WKY e acompanhadas por redução de AGT no PVN e NTS dos S e redução de AGT e AT1 no RVL dos WKY. / The aerobic training (T) for 12 weeks was effective in reducing the mRNA of angiotensinogen(AGT) in NTS of SHR. We evaluate in SHR and WKY time-course changes of T on blood pressure, heart rate, AGT and AT1 mRNA and protein (PVN, NTS and RVL). WKY and SHR were T for 0,1,2,4,8 or 12 weeks, the baseline BP and HR were recorded and mRNA(RT-PCR) and Immunofluorescence for AGT, AT1 and NeuN were made. SHR(vs. WKY) had high BP(174±2 vs 123±2 mmHg), HR and mRNA of AT1 in the NTS(+67%). T reduced the BP only in SHR(-6.5% from T4 to T12) and HR in SHR in T4 and WKY in T8. In the SHR, T reduced the AGT mRNA within the PVN (-34% in T2) and NTS (-30% in T4), and AT1 mRNA only in T12 in PVN(-56%) and NTS(-39%). In WKY, T decreased of both AGT(-49%) and AT1(-58%) mRNA in the RVL at T8. Immunofluorescence localized these proteins, confirming the mRNA content changes induced by T. Our data indicate that the fall of BP and HR are progressive and appear earlier in SHR than in WKY and are accompanied by reduced AGT in the PVN and NTS of the SHR and reduced AGT and AT1 in RVL of WKY.

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