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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.
451

Torta de maca?ba como aditivo em silagem de capim-elefante

Silveira, Hugo Vin?cius Lelis 04 August 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-08-07T17:20:56Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) hugo_vinicius_lelis_silveira.pdf: 433611 bytes, checksum: f5247fb74b25f1503149b9815b9e8d6e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-10-05T19:15:12Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) hugo_vinicius_lelis_silveira.pdf: 433611 bytes, checksum: f5247fb74b25f1503149b9815b9e8d6e (MD5) / Made available in DSpace on 2018-10-05T19:15:12Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) hugo_vinicius_lelis_silveira.pdf: 433611 bytes, checksum: f5247fb74b25f1503149b9815b9e8d6e (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Objetivou-se com este trabalho avaliar os efeitos da adi??o de doses crescentes do subproduto torta de polpa de Acrocomia aculeata (maca?ba) sobre o valor nutritivo, caracter?sticas fermentativas, perdas do processo fermentativo e influ?ncia na estabilidade aer?bica de silagens de capim-elefante (Pennisetum purpureum Schum.). O delineamento experimental foi inteiramente casualizado com 4 repeti??es. Os tratamentos foram constitu?dos pela forrageira capim-elefante aditivada de seis doses de torta de polpa de coco de maca?ba com base na mat?ria natural (0, 6, 12, 18, 24, 30%). A planta forrageira passou por per?odo de 150 dias de amarmazenamento em silos experimentais de polietileno (PVC). Foi determinado o valor nutritivo, as caracter?sticas fementativas, as perdas e a estabilidade aer?bia.Verificou-se efeito linear crescente (P <0,05) das doses de TPCM sobre o teor m?dio de mat?ria seca (MS), extrato et?reo (EE), lignina, carboidratos n?o fibrosos (CNF) e digestibilidade in vitro da mat?ria seca (DIVMS) das silagens de capim-elefante, entretanto, os teores de fibra em detergente neutro (FDN), fibra em detergente neutro corrigida para cinzas e prote?na (FDNcp), fibra em detergente ?cido (FDA) e prote?na bruta (PB) foram reduzidos linearmente (P<0,05) ? medida que se elevou a adi??o de TPCM. A inclus?o de TPCM elevou linearmente (P<0,05) os valores de pH e reduziu os valores de nitrog?nio amoniacal (N-NH3) das silagens. Os valores de produ??o de efluentes na silagem decresceram linearmente (P<0,05) com a inclus?o do aditivo. Os valores de perda por gases apresentaram resposta quadr?tica (P<0,05) ? medida que se elevou a adi??o de TPCM nas silagens. A estabilidade aer?bica foi afetada nas silagens de capim-elefante, mostrando uma eleva??o na estabilidade a medida que se elevava a dose de inclus?o da TPCM. De forma geral a adi??o da TPCM melhora o valor nutritivo e os par?metros fermentativos da silagem de capim-elefante, sendo recomendado a inclus?o de 15 % desse aditivo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / The objective of this work was to evaluate the effects of the addition of doses of Acrocomia aculeata pulp by-product (maca?ba) on nutritive value, fermentative characteristics, losses of fermentation and influence on aerobic stability of Elephant grass silages (Pennisetum Purpureum Schum.). The experimental design was completely randomized with 4 replicates. The treatments were constituted by Elephant grass forage with six leves of maca?ba coconut pulp cake (MCPC) based on natural matter (0, 6, 12, 18, 24, 30%). The silos were storage by 150 days in experimental polyethylene (PVC) silos. The nutritive value, fementative characteristics, losses and aerobic stability were determined. There was an increasing linear effect (P <0.05) of MCPC doses on the mean dry matter (DM), ether extract (EE), non-fibrous carbohydrates (NFC) and in vitro dry matter digestibility (IVDMD) of Elephant grass silages. However, neutral detergent fiber (NDF), neutral detergent fiber corrected for ash and protein (FDNcp) , acid detergent fiber (ADF), and crude protein (CP) were linearly reduced (P <0.05) as the addition of MCPC was increased. The inclusion of MCPC linearly increased (P <0.05) the pH values and reduced the ammoniacal nitrogen (N-NH3) values of the silages. The values of effluent production in the silage decreased linearly (P <0.05) with inclusion of the additive. The gas loss values presented a quadratic response (P <0.05) as the addition of MCPC to the silages increased. Aerobic stability was affected in Elephant grass silages, showing an increase in stability as the inclusion dose of MCPC was increased. In general, the addition of MCPC improves the nutritive value and fermentative parameters of Elephant grass silage. Recommended the inclusion of 15% of this additive.
452

The effects of aerobic exercise and physical activity on progression of Alzheimer's disease and mild cognitive impairment

Korgaonkar, Chaitali Nitin 03 November 2016 (has links)
This abstract will provide a brief overview of the following literature review. Alzheimer’s disease (AD) is the most common cause of dementia, and is a rapidly growing public health concern, as an increasing number of the world’s population is living well beyond 65 years of age. Alzheimer’s Disease is a progressive neurodegenerative condition, first presenting with mild memory impairment, and advancing over the course of years to profound memory loss, complete immobility, lack of speech and facial recognition. Currently, only palliative treatments are available to delay the progression of the disease, and lessen the severity of the cognitive impairment. However, until a cure is available, researchers and physicians have turned their attention to alternate therapies, one of the most important being exercise. Research efforts have now turned to examining the relationship between the positive physiological responses to exercise, and attenuation of the classic neurodegenerative patterns in patients with AD. The current study examined the effects of aerobic exercise, strength training and resistance-based exercise, and multimodal exercise (containing both of the aforementioned exercise modalities) on the physical and mental/cognitive health of patients with mild cognitive impairment (MCI) and AD. Thus far, exercise therapy has proven to be of great potential value as a supplement to pharmacological treatment, as well as a stand-alone prescription for patients with a milder form of cognitive impairment due to the onset of a neurodegenerative condition. The benefits can be grouped into two categories, cognitive and physiological. The effects on cognitive function range from improved memory to increased independence in activities of daily living, and the physiological effects range from improved clearance of amyloid beta plaques in the brain, to reduction of neuroinflammatory processes. The available research on this subject is extensive, covering a variety of exercise modalities at different intensities, and taking into consideration effects on individuals with MCI, early AD, and advanced AD. The general consensus is that continued, long-term adherence to an appropriate exercise routine can delay cognitive decline, and help patients with neurodegenerative diseases to live independently for a longer period of time. The improvements in cognition, memory, immediate recognition, and other related cognitive functions are mostly attributed to the heightened health of the brain tissue and neural circuitry due to exercise. Exercise (mainly aerobic) enhances cerebral blood flow, improves cardiovascular health, reduces the risk for type 2 diabetes mellitus, and has several other important effects that prevent the formation of pathological biomarkers of AD and promote neurogenesis. Atrophy of regions such as the hippocampus, amygdala, and cerebral cortex can be prevented, and reversed to a certain extent, as a result of long-term exercise therapy. The results of current research could assist physicians and caregivers to provide the appropriate type and intensity of exercise to patients with early, intermediate, and advanced stages of Alzheimer’s disease. Proactive exercise therapy for individuals with a known family history of neurodegenerative disease may help to maintain brain volume, specifically in the hippocampus, and reduce the risk of severe cognitive impairment. Future directions for research include examining the combined effects of pharmacological treatment and exercise therapy, and determining the average amount of time by which exercise delays the progression of early stage cognitive impairment to advanced impairment. Key Terms: aerobic exercise, Alzheimer’s disease, amyloid plaque, hippocampus, mild cognitive impairment, neurodegeneration, neurofibrillary tangle
453

Exercise, arterial pressure control & systemic O₂ tension : implications for post exercise hypotension in hypertension

New, Karl James January 2008 (has links)
This thesis presents four studies investigating the phenomenon of post exercise hypotension in the human condition of pre (borderline)-hypertension. Study one investigated the effects of an acute bout of 30-minutes upright cycling on post exercise haemodynamics and compared the results to a non-exercise control condition. 9 pre-hypertensive males, mean arterial pressure (MAP) = 106 ± 5 mmHg (50 ± 10 yr), not on medication, were studied for 6 hours following 30-minutes of cycle exercise at 70% maximal oxygen consumption and following 30-minutes of seated rest. Results demonstrate that moderate intensity exercise exerts a modest fall (~6 mmHg) in arterial pressure with the hypotension sustained for 6-hours post exercise. The fall in arterial pressure equates to a significantly reduced after load when compared to both pre-exercise baseline and non-exercise control data taken at the same time of day. The arterial pressure responses transcended into a sustained reduction (20%) in systemic vascular resistance and reciprocal increase in vascular conductance for up to 2-hours post-exercise. Venous atrial natriuretic peptide (ANP) demonstrated an elevation (44%) following exercise and a significant decline (33%) in the post-exercise period mirroring the haemodynamic response. This research reveals that acute exercise is capable of sustained reductions in arterial pressure and vascular resistance beyond the usual labile fluctuations and that the octapeptide ANP may exert a modulatory influence over the post-exercise response. Increases in 02 tension beyond the physiological range induces complex effects on the circulatory system with a dominant vasoconstriction following hyperoxia. The purpose of study 2 was to assess the effects of hypoxic (16% 02) and hyperoxic (50% 62) exercise on subsequent haemodynamic control when compared with normoxia. 9 pre-hypertensive males, MAP = 106 ± 5 mmHg (50 ±10 yr), not on medication, performed 30-minutes of cycle exercise at 70% normoxic maximal oxygen consumption in hypoxia (16% O 2 ), hyperoxia (50% O 2) and normoxia(21% O2 ). Hyperoxic exercise blunted post-exercise haemodynamics by significantly attenuating the reductions (from normoxic baseline) in SVR (-45%, PO.05 vs. normoxic & hypoxic exercise immediately post-exercise) that persisted throughout 120-minutes recovery in normoxia (-35% vs. normoxic & hypoxic exercise, during recovery) and elicited a mildly hypertensive effect, with regards to MAP, whereas normoxic and hypoxic exercise elicited a hypotension compared to baseline (P < 0.05). Circulating ANP was decreased in the hyperoxic trial when compared with normoxic and hypoxic exercise [24.3 (13.4) v. 31.5 (16.3) and 29.6 (13.9) pg/ml, respectively; P < 0.05, pooled for state]. Changes in MAP were related to changes in ANP concentration only following hyperoxic exercise (r = 0.50, P < 0.01). These findings indicate that acute modest hyperoxia reflexively induces measurable physiological derangement partly explained by decreased circulating concentrations of ANP. Study three determined the role of free-radical mediated oxidative stress and redox regulation of circulating NO metabolism as a primary modulator of vascular tone following exercise in pre-hypertensive humans. Utilising the same cohort and exercise protocol as in study 1 venous blood was sampled from an antecubital vein. Plasma NO metabolites nitrate (NO" 3 ) and nitrite (NO"2 ) were determined fluorometrically, whilst S-Nitrosothiol (RSNO) concentrations were assayed by the Saville reaction Indirect markers of oxidative stress were determined spectrophotometrically detecting lipid hydroperoxides (LOOH). Exercise led to a delayed increase in LOOH by 60- minutes post-exercise (0.69 ± 0.13 v. 0.86 ± 0.18 umol/1, respectively, P < 0.05), that remained elevated until termination of the trial 6-hours post-exercise. NO'a significantly fell below baseline by 120-minutes post-exercise (10.8 ± 3.3 v. 1.1 ±1.1 u.mol/1, respectively, P < 0.05), remaining attenuated for the remainder of the study.NO'i and RSNO were unmodified in the post-exercise period. In parallel to this finding the data also indicates a significant blunting in the hyperaemic response [SVR decreased from a 31% reduction immediately (within 1-minute) post-exercise to -13 and 8% at 60- and 120-minutes post-exercise, respectively, P < 0.05] and reversal of the hypotension (P < 0.05) over the same time frame as the augmented lipid peroxidation and attenuated circulating NO~3. These results indicate that augmented oxidative stress exerts a deleterious effect on post-exercise haemodynamics and implicates a potential redox regulation pathway of NO as being a mechanism by which free radical-induced oxidative stress blunts the degree of PEH in the recovery period. The final study investigated the potential role of a redox-mediated regulation of circulating NO bioavailability as a modulator of the augmented vasoconstriction following hyperoxic exercise. The same cohort and exercise protocol were employed as in study 2 and venous blood was assayed for NO"3 , NO'a, RSNO, LOOK, & lipid /water-soluble antioxidant concentrations. Similar adverse haemodynamic effects were noted following hyperoxic exercise as reported previously in study 2. RSNO showed a significant increase following hypoxic exercise only (P < Q.Q5, state x time, interaction), whereas NO~3, NO~2 and LOOH failed to differ between conditions (P > 0.05, main effect for state [02] and state x time, interaction effects). Ascorbic acid was mobilised in response to hyperoxic exercise when compared to normoxia (P < 0.05, main effect for state [O2] and state x time, interaction effects) being significantly elevated by 120-minutes post-exercise in hyperoxia compared to normoxia and hypoxia [75.1 (31) v. 39.5 (18.3) v. 46.7 (14.2) |amol/l, respectively, P < 0.05]. This data demonstrates an effective endogenous antioxidant response and argues against a redox regulation pathway of NO metabolism as a primary mediator of blunted vasodilatation in this scenario. This elucidates a more complex regulation of arterial tone, resulting from a metabolic pathway independent of NO in older subjects with pre-hypertension. This work demonstrates that (1) aerobic exercise exerts a hypotensive effect in humans with pre-hypertension, (2) ANP plays a part in the vasodilatation following exercise, (3) Free-radical mediated oxidative stress & subsequent modulation of NO metabolism exerts a deleterious influence on post-exercise haemodynamics (4) Acute hyperoxic exercise induces a sustained vasoconstriction that is mediated via circulating ANP concentration but not by redox regulation of NO metabolism.
454

Využití cihelného a betonového recyklátu stavebních odpadů při kompostování biodegradabilních odpadů / Utilization of construction waste particularly recycled bricks and concrete during biodegradable waste composting

NOVÁČKOVÁ, Pavlína January 2015 (has links)
It is known that certain inert substances significantly improve the process of aerobic degradation of organic mass during composting. The cause is not completely clear yet, but it improves catalytic oxidation or hydrolysis process rather than aeration at the surface of inert substance. Generally, it is not clear, whether this benefit effect occurs during synthesis process of "humification", which should happen after decay of organic mass in compost.
455

Efeitos da manipulação da ordem dos tipos de exercício durante o treinamento concorrente nas adaptações neuromusculares e cardiorrespiratórias em homens idosos

Cadore, Eduardo Lusa January 2012 (has links)
O objetivo da presente tese foi investigar os efeitos da ordem das modalidades de treino de força e aeróbico nas adaptações neuromusculares e cardiorrespiratórias ao treinamento concorrente em idosos. Vinte seis homens idosos saudáveis (64,7 ± 4,1 anos) foram distribuídos em 2 grupos de treino concorrente: treino de força executado antes do treino aeróbico (GFA, n=13), e treino aeróbico executado antes do treino de força (GAF, n = 13). Os indivíduos treinaram 12 semanas, 3 vezes por semana executando os dois tipos de treinamento na mesma sessão. A espessura muscular (EM) de membros superiores (músculos do quadríceps) e inferiores (flexores do cotovelo) foram mensuradas com a técnica de ultrasonografia. Foram avaliados a força de membros superiores (flexores do cotovelo) e inferiores (extensores do joelho) com o teste de uma repetição máxima (1RM), o pico de torque isométrico (PTiso) dos extensores e flexores do joelho, e a taxa de produção de força (TPF) dos extensores do joelho em um dinamômetro isocinético. Além disso, a tensão específica foi avaliada através do quociente entre os valores de 1RM/2 e o somatório dos valores de EM do quadríceps. A atividade neuromuscular máxima e a economia neuromuscular (valores root mean square obtidos a 50% do PTiso normalizados pela atividade neuromuscular máxima) dos músculos vasto lateral (VL) e reto femoral (RF) foram avaliadas com eletromiografia (EMG) de superfície. O consumo de oxigênio de pico (VO2pico), a potência máxima (Wmáx), os limiares ventilatórios absolutos (LV1 e LV2) e relativos (LV1% e LV2%) e as potências nos limiares (WLV1 e WLV2) foram avaliadas em um teste incremental em ciclo ergômetro. Ambos os grupos aumentaram os valores de 1RM e a tensão específica de membros inferiores (P<0,001), mas os aumentos foram maiores no grupo GFA do que em GAF [(35,1 ± 12,8 vs. 21,9 ± 10,6%, respectivamente, P<0,01) e (27,5 ± 12,7 vs. 15,2 ± 10,3%, respectivamente P<0,02)]. Ambos os grupos aumentaram os valores de 1RM de membros superiores (P<0,001), o PTiso dos flexores e extensores do joelho (P<0,001), TPF dos extensores do joelho (P<0,05), a EM dos extensores do joelho e flexores do cotovelo (P<0,001), a atividade neuromuscular máxima do VL e RF (P<0,01 a 0,05) e a economia neuromuscular do VL (P<0,001), sem diferenças entre os grupos. A economia neuromuscular do RF melhorou somente em GFA (P<0,01) e esse aumento foi maior (P<0,05) que em GAF. Houve aumento no VO2pico (P<0,001), na Wmáx, (P<0,001) e na WLV2 (P<0,001) em GAF e GFA, sem diferenças entre os grupos. Somente o grupo GFA aumentou a WLV1 (P<0,05). Não houve modificações nos valores de LV1, LV2, LV1% e LV2% nos grupos. A execução do treinamento concorrente com o treino de força realizado antes do treino aeróbico resulta em maiores ganhos na força máxima e economia neuromuscular dos membros inferiores, bem como resulta em maiores ganhos na potência do primeiro limiar ventilatório. / The aim of this study was investigate the effects of different intra-session exercise orders in the neuromuscular and cardiorespiratory adaptations induced by concurrent training in elderly. Twenty-six healthy elderly men (64.7 ± 4.1 years), were placed into two concurrent training groups: strength prior to (GFA, n=13) or after (GAF, n=13) endurance training. Subjects trained strength and endurance training during 12 weeks, three times per week performing both exercise types in the same training session. Upper and lower body muscle thickness (MT) were determined by ultrasonography. Upper (elbow flexors) and lower body (knee extensors) one maximum repetition test (1RM), lower-body isometric peak torque (PTiso) and rate of force development (RFD) of knee extensors were evaluated as strength parameters. In addition, the specific tension was evaluated by the quotient between knee extensors 1RM/2 and the quadríceps femoris MT. Lower-body maximal electromyographic activity and the neuromuscular economy (root mean square values at 50% of pre training PTiso normalized by maxima neuromuscular activity) of vastus lateralis (VL) and rectus femoris (RF) muscles were determined by surface electromyography. The peak oxygen uptake (VO2peak), maximum aerobic workload (Wmáx), absolute (VT1 and VT2) and relative (VT1% and VT2%) ventilatory thresholds, as well as workloads at VT1 and VT2 (WVT1 and WVT2) were evaluated during a maximal incremental test on a cycle ergometer. Both GFA and GAF increased the lower-body 1RM and specific tension, but the increases observed in the GFA were greater than GAF [(35.1 ± 12.8 vs. 21.9 ± 10.6%, respectively, P<0.01) and (27.5 ± 12.7 vs. 15.2 ± 10.3%, respectively, P<0.02)]. In addition, GFA and GAF increased upper-body 1RM, PTiso of knee extensors and flexors (P<0.001), RFD of knee extensors (P<0.05), MT of elbow flexors and knee extensors (P<0.001), maximal neuromuscular activity of VL and RF (P<0.01 to 0.05), and, neuromuscular economy of VL (P<0.001), with no differences between groups. The neuromuscular economy of RF was improved only in GFA (P<0.01) and this increase was greater that GAF (P<0.05). There were increases in the VO2peak (P<0.001), Wmáx (P<0.001) and WVT2 (P<0.001), with no difference between GFA and GAF. Only GFA increased the WVT1 (P<0.05). There were no modifications after training in the VT1, VT2, VT1%, and VT2%. Performing strength prior to endurance exercise during concurrent training resulted in greater maximal strength gains and neuromuscular economy of lower-body, as well as greater changes in the in the power at first ventilatory threshold.
456

Efeitos do treinamento concorrente na força e ativação muscular, capacidade aeróbica e em hormônios e esteróides em homens idosos

Cadore, Eduardo Lusa January 2009 (has links)
O treinamento concorrente de força e endurance têm sido amplamente investigado em diversas populações. Contudo, poucos estudos compararam seus efeitos com o treino de força e endurance isolados em indivíduos idosos. Sendo assim, o objetivo desse estudo foi investigar os efeitos do treinamento concorrente na força e ativação muscular, capacidade de endurance e concentrações hormonais em homens idosos. Vinte e três homens saudáveis (65 ± 4 anos) foram divididos em 3 grupos: treino concorrente (GC, n=8), treino de força (GF, n=8) e treino aeróbio (GA, n=7). Cada grupo treinou 3 vezes por semana durante 12 semanas o treinamento de força, aeróbio ou ambos tipos de treinamento na mesma sessão. Antes e após o período de treino, os indivíduos foram avaliados em parâmetros relacionados à força muscular, ativação muscular isométrica e dinâmica, capacidade de endurance e concentrações hormonais. Houve aumento na força muscular dinâmica de membros inferiores em todos os grupos (P<0,05), sendo que o aumento percentual foi maior em GF (67%) do que GC (41%) e esse maior que em GA (25%) (ambos P<0,01). Somente GF e GC aumentaram a força de membros superiores (P<0,01). Houve aumento significativo na força isométrica e ativação muscular máxima somente em GF (P<0,05), bem como diminuição na ativação muscular submáxima isométrica para uma mesma carga em GF após o treinamento (P <0,05) nos músculos avaliados. Além disso, somente GC e GA aumentaram a capacidade de endurance (P<0,05), sem nenhuma diferença entre esses grupos, sendo que GC e GA diminuíram a atividade muscular dinâmica no reto femoral para uma mesma carga após o treinamento. Ainda, houve diminuição significativa na testosterona livre em GA (P<0,05). Os presentes resultados sugerem que os diferentes tipos de treinamento resultaram em diferentes adaptações em variáveis de performance, bem como parâmetros neuromusculares e endócrinos em indivíduos idosos. O efeito de interferência observado no treino concorrente pode estar relacionado com prejuízo nas adaptações neurais. / Concurrent strength and endurance training have been widely investigated in many populations. However, few studies have compared its effects with strength and endurance training separately. Thus, the aim of the present study was to investigate the effects of concurrent training on muscle strength and activation, endurance capacity and hormonal concentrations in elderly men. Twenty-three healthy men (65 ± 4 years) were matched in 3 groups: concurrent (CG, n=8), strength (SG, n=8) or aerobic training group (AG, n=7). Each one trained 3 times a week during 12 weeks strength, aerobic in cycle ergometer or both in the same session. Before and after training period, subjects were evaluated in parameters related to muscle strength, dynamic and isometric muscle activation, endurance capacity and serum hormones. There were significant increases on lower-body strength in all groups (P<0.05), with higher increases in SG (67%) than CG (41%) and both higher than AG (25%) (both P<0.01). Only SG and CG increased the upper-body strength (P<0.01). There were significantly increases in isometric strength and maximal muscle activation only in SG (P<0.05), as decreases in isometric submaximal muscle activation to the same load in SG (P <0.05) after training in the muscles evaluated. Indeed, only CG and AG have increases endurance capacity (P<0.05), with no differences between these groups, and both CG and AG decreased the dynamic muscle activation in rectus femoris to the same power after training. In addition, there were significant decreases on free testosterone in AG after training. The present results suggested that the different types of training resulting in different adaptations in performance variables, as like as neuromuscular and endocrine parameters in elderly subjects. The interference effect observed to concurrent training could be related with impairment of neural adaptations.
457

Efeitos de dois modelos de treinamento de hidroginástica nas respostas cardiorrespiratórias e na força de mulheres idosas : um ensaio clínico randomizado controlado

Kanitz, Ana Carolina January 2015 (has links)
A procura crescente por atividades aquáticas tem estimulado o aumento de estudos nessa área objetivando uma melhor prescrição para diferentes populações. A hidroginástica, em específico, tem sido amplamente indicada para a população idosa, devido aos seus inúmeros benefícios já documentados, principalmente na força muscular e nas respostas cardiorrespiratórias. Entretanto, ainda não se sabe qual o modelo ideal para essas melhoras, visto que as metodologias utilizadas são muito distintas entre os estudos. Desta forma, o objetivo do presente estudo foi avaliar os efeitos de dois modelos de treinamento de hidroginástica nas respostas cardiorrespiratórias e na força de mulheres idosas. Para tanto, participaram do estudo 69 mulheres idosas e sedentárias (60-75 anos) que foram divididas nos dois grupos de treinamento e no grupo controle: grupo de hidroginástica aeróbio (GA, n=23), grupo de hidroginástica de força (GF, n= 23) e grupo controle de relaxamento em imersão (GC, n=23). As intervenções tiveram uma duração de 10 semanas e foram realizadas sessões de 45 minutos duas vezes por semana. Antes e após esse período foram realizadas duas sessões de avaliações, sendo uma destinada aos testes de força muscular dinâmica máxima e outra para as avaliações cardiorrespiratórias em repouso e em máximo esforço. Para análise estatística utilizamos a Generalized Estimating Equations (GEE), com teste post hoc de Bonferroni (α=0,05). Os resultados demonstraram uma diminuição significativa da pressão arterial sistólica (GA: - 4%; GF: -6%; GC: -5%) e diastólica (GA: -1%; GF: -7%; GC: -6%) de repouso para todos os grupos avaliados, sem diferenças entre eles. A frequência cardíaca de repouso, no segundo limiar ventilatório e de pico não modificaram com as intervenções realizadas. Em contrapartida, o GA apresentou aumentos significativos no consumo de oxigênio no segundo limiar ventilatório (17%) e de pico (14%) e esse comportamento não foi observado nos demais grupos avaliados. Em relação à força muscular, todos os grupos apresentaram um aumento significativo da força dinâmica máxima de extensão de joelho sem diferenças entre eles (GA: 11%; GF: 8%; GC: 5%), a força dinâmica máxima de flexão de joelho aumentou no GA (14%) e no GF (18%) e, por fim, a força de flexão horizontal de ombro não apresentou diferenças significativas após as intervenções realizadas. Assim, concluímos que as três intervenções realizadas demonstraram melhoras significativas na pressão arterial de repouso. O treinamento de força na hidroginástica proporciona aumentos significativos na força muscular de membros inferiores. Por fim, o treinamento aeróbio na hidroginástica parece ser um modelo de treino efetivo tanto para aumentos na força muscular de membros inferiores quanto para melhoras nas respostas cardiorrespiratórias de mulheres idosas sedentárias. / The growing demand for aquatic exercises has stimulated the increase of studies in this area aiming at a better prescription for different populations. The water-based exercise in particular has been widely recommended for the elderly due to its numerous benefits already documented, especially in muscle strength and cardiorespiratory responses. Thus, the aim of this study was to evaluate the effects of two water-based training models on the cardiorespiratory and strength responses in older women. Sixty-nine elderly and sedentary women (60-75 years) were divided into two water-based training groups and control group: aerobic group (AG, n = 22), resistance group (RG, n = 23) and control group of relaxation in immersion (CG, n = 24). The interventions had a 10-week duration and 45 minute sessions were held twice a week. Before and after this period there were two sessions assessments, one destined to maximal dynamic strength test and one for cardiorespiratory evaluations at rest and at maximal effort. The Generalized Estimating Equations (GEE), with post hoc Bonferroni was used to statistical analysis of data (α = 0.05). The results showed a significant decrease in systolic blood pressure (AG: -4%; RG: -6%; CG: -5%) and diastolic (AG: -1%; RG: -7%; CG: -6%) at rest for all the groups, with no differences between them. The resting, ventilatory threshold and peak heart rate did not change with the interventions. In contrast, the GA showed significant increases in oxygen consumption in the second ventilatory threshold (17%) and peak (14%) and this behavior was not observed in the other groups assessed. Regarding muscular strength, all groups showed a significant increase in maximal dynamic knee extension without differences between them (GA: 11%; GF: 8%; GC: 5%), the maximum dynamic strength of knee flexion increased in GA (14%) and GF (18%) and, finally, the strength of shoulder horizontal flexion showed no significant differences after interventions. Thus, we conclude that the three interventions showed significant improvements in blood pressure at rest. The strength training in the water aerobics provides significant increases in muscle strength of the lower limbs. Finally, the aerobic waterbased training seems to be an effective training model for both increases in muscle strength of the lower limbs and to improvements in cardiorespiratory responses among sedentary older women.
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Determinação da potência aeróbia em jogadores amadores de rugby Union XV a apartir de testes de campo Ricardo Tannhauser Sant'Anna / Measurement of aerobic power in amateur rugby union XV players from field tests

Sant'Anna, Ricardo Tannhauser January 2015 (has links)
O rugby union XV é um esporte coletivo e de invasão praticado em um campo gramado por duas equipes compostas por 15 jogadores cada e divididos em dois grupos denominados forwards (8 jogadores) e backs (7 jogadores) de acordo com a função desempenhada durante a partida. As demandas física e fisiológica do rugby exigem que os atletas recuperem suas reservas energéticas em pequenos intervalos ou durante exercícios de baixa intensidade. Desta forma, o consumo máximo de oxigênio (VO2Máx), indicador de potência aeróbia, torna-se uma variável importante para o desempenho na modalidade. O objetivo deste estudo foi verificar a possibilidade de predizer a potência aeróbia em jogadores amadores de rugby union XV utilizando os testes de campo Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IRT1) e 5 m Multiple Shuttle Test (5-m MST). Para isso, 42 jogadores, 22 forwards e 20 backs, foram avaliados em três etapas: (1) em laboratório com teste máximo em esteira; (2) teste de campo definido por sorteio na primeira etapa; e (3) segundo teste de campo. Com os dados obtidos nos três testes foram realizadas análises descritivas, de comparação, de correlação, de regressão e de concordância. Dentre os principais resultados, backs, em comparação a forwards, apresentaram maior VO2Máx (respectivamente, 61,7 ± 15 ml.kg-1.min-1 e 51,6 ± 10,1 ml.kg-1.min-1), resultado no Yo- Yo IRT1 (respectivamente, 16,4 ± 0,8 e 14,9 ± 0,9) e distância final no Yo-Yo IRT1 (respectivamente, 1283,3± 312,5 m e 792 ± 277,6 m). Foram encontradas correlações significativas entre resultado final e distância final total obtidas no Yo-Yo IRT1 e o VO2Máx relativo a massa corporal (respectivamente, r = 0,425 e r = 0,459). Utilizandose a distância final percorrida no Yo-Yo IRT1, o VO2Máx, em jogadores de rugby, pode ser estimado com a aplicação da equação VO2Máx = 0,016(DIST Yo-Yo) + 40,578. / Rugby Union XV is a sport played in pitches by two teams of 15 players each. The players are divided into two groups according to the role in the game: the forwards (8 players) and the backs (7 players). During a match, the physical and physiological demands of rugby require that athletes recover its energy reserves in shorts intervals or during low-intensity exercise. Thus, the maximal oxygen uptake (VO2Max), an aerobic power index, becomes an important variable for the performance in the discipline. The objective of this study was to verify the possibility to predict the aerobic power in rugby union XV amateur players using the field tests Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IRT1) and 5 m Multiple Shuttle Test (5-m MST). Forty-two players, 22 forwards and 20 backs, were evaluated in three phases: (1) in a laboratory with maximum treadmill test; (2) field test set by a draw in the first phase; and (3) second field test. Descriptive, comparison, correlation, regression and level of agreement analyses were performed. Among the mayor results, backs, compared with forwards, reported a higher VO2Max (respectively 61.7 ± 15 ml.kg-1.min-1 and 51.6 ± 10.1 ml.kg- 1.min-1), Yo-Yo IRT1 results (respectively 16.4 ± 0.8 and 14.9 ± 0.9), and Yo-Yo IRT1 total distance (respectively 1283.3± 312.5 m e 792 ± 277.6 m). Significant correlations were found between the result and total distance on the Yo-Yo IRT1 and the VO2Max (respectively r = 0.425 and r = 0.459). Using the total distance covered on the Yo-Yo IRT1, the VO2Max in rugby players, can be estimated using the equation VO2Max = 0.016(DIST Yo-Yo) + 40.578.
459

Efeitos do treinamento aeróbio, em hidroginática, na reatividade vascular de homens obesos

Veiga, Alessandra Dalla Rosa da January 2008 (has links)
O objetivo do presente estudo foi verificar o efeito de um treinamento aeróbio em hidroginástica na reatividade vascular de homens obesos. Vinte e sete homens, com IMC acima de 30, com média de idade = 42 anos, fizeram parte da amostra deste estudo, onde foram divididos aleatoriamente em dois grupos. Um grupo controle (GC), que não realizou treinamento (inativo) com N=14, e outro grupo intervenção (GI), que participou do treinamento, 3 vezes/semana, durante 12 semanas, com N=13. Todos os voluntários participaram de 4 sessões: 1) sessão de avaliação para caracterização da amostra (anamnese, massa corporal, estatura, % de gordura, IMC, pressão arterial, freqüência cardíaca de repouso); 2) uma sessão para avaliar a capacidade cardiorrespiratória através de um teste de esforço progressivo até exaustão; 3) uma sessão de avaliação do perfil bioquímico (PCR, plaquetas, glicose, colesterol total, HDL-C, LDL-C e triglicerídeos) e, 4) uma sessão para avaliar a função vascular da artéria braquial em quatro protocolos (repouso, hiperemia reativa, handgrip e vasodilatador sublingual) através de Eco-doppler. O GI participou durante 12 semanas de um treinamento aeróbio em hidroginástica, com intensidade entre 50% à 80% da FC de reserva, este treinamento seguiu uma periodização linear. Para análise estatística foi utilizado o procedimento MIXED, do software estatístico SAS, usando a teoria de modelos mistos para medidas repetidas e as estruturas de matrizes de variância e covariâncias, tendo como o critério de informação o de Akaike. Foi encontrada diferença significativa entre os grupos (GC e GI), para as variáveis de PAS, % de gordura e LDL-C. Sendo que, o GI apresentou uma redução significativa, quando comparado com o GC, antes e depois do período de treinamento. Conclui-se a partir dos resultados obtidos no presente estudo, que, o treinamento aeróbio em hidroginástica: melhora o perfil lipídico; reduz a massa corporal; reduz o % de gordura; os níveis dos marcadores inflamatórios, bem como reduz a PAS em sujeitos obesos, auxiliando na prevenção de eventos cardiovasculares. / The aim of this study was to verify the effect of a water hydrogymnasctics aerobic training in vascular reactivity in obese male. Twenty-seven men, with BMI over 30, were part of the sample, where they were randomly divided into two groups: a Control Group (CG), which did not trained (inactive) with N=14, and another intervention group (IG), which took part in the training for 12 weeks, with N=13. Data collection consisted in an evaluation protocol applied before and after the aerobic training. This protocol was structured into four sessions, in which all voluntaries took part: 1) an evaluation session to characterize the sample (anamnesis, body mass, height, percentage of fat, BMI, blood pressure, heart frequency in rest); 2) a session to evaluate cardio respiratory capacity through and effort test (exhausting time); 3) a session to evaluate the biochemical profile (PCR, plaquelet, glucose, total cholesterol, HDL-C, LDL-C and triglycerides) and; 4) a session to evaluate the vascular function of the brachial artery in four protocols (rest, reactive hyperemia, handgrip and sublingual vasodilatation) through an Eco-Doppler. For 12 weeks the IG took part in a water hydrogymnasctics aerobic training, with intensity from 50% to 80% of FC de reserve, this training followed a linear periodization. For the statistic analysis of this study, the MIXED procedure was used, from SAS statistic software, using the mix model theory for repeated measures and the structure of variances and co-variances matrix, having Akaike's information criterion. Significant differences between the two groups (CG and IG) regarding SBP variables, percentage of fat and LDL-C were found. The IG group presented a significant reduction, compared to the CG, before and after the training. The vascular function variable did not present significant differences between the groups. It can be concluded, from the results obtained in this study, that water gym aerobic training improves lipid profile, reduces percentage of fat; and reduces SBP in obese subjects, helping in the prevention of cardiovascular events.
460

Exercícios concorrente e aeróbico em ambiente quente e termoneutro : respostas fisiológicas e perceptivas de meninas obesas

Fontoura, Andrea Silveira da January 2012 (has links)
Introdução: O exercício é conhecido como uma das ferramentas mais poderosas para prevenir e controlar a obesidade. No entanto, as razões pelas quais indivíduos obesos parecem ser menos dispostos do que aqueles com peso normal para participar e aderir a programas de exercícios são ainda desconhecidas. Uma das hipóteses é que as altas taxas de abandono tipicamente encontradas entre os adolescentes obesos pode ser devido ao tipo de exercício prescrito, e/ou uma capacidade termorregulatória comprometida. A interação entre exercício e excesso de peso pode alterar algumas variáveis, tais como, temperatura corporal, percepção de esforço, conforto térmico e irritabilidade, especialmente se os programas de exercícios são realizados em ambientes com altas temperaturas. Objetivo: Este estudo investigou as respostas fisiológicas e perceptivas em adolescentes obesas em sessões de exercícios concorrente (EC) e de exercícios aeróbico (EA), em duas condições ambientais: calor (C) e termoneutro (Tn). Métodos: Doze meninas púberes obesas (12,7±0,6 anos, 49,9± 3,0% de gordura) fisicamente ativas e aclimatizadas ao calor foram designadas para participar de quatro sessões de testes (EA e EC onde no EA foi de 40 minutos e consistia de cicloergômetro (60-70% do VO2pico) em duas condições ambientais: Aeróbico termoneutro (ATn) em que a temperatura foi mantida a 22-25 °C, humidade relativa entre 55-60 %; Aeróbico Calor (AC) em que a temperatura foi mantida entre 35-37 ºC, e uma humidade relativa entre 40-45%. As sessões EC foram organizados em quatro períodos (10 minutos cada), alternando cilcoergômetro (60-70% VO2pico) e duas séries de nove exercícios de força (12-15 repetições a 60-70% de 1-RM). As sessões de EC também foram testadas sob as mesmas condições acima mencionadas (concorrente termoneutra - CTn e concorrente calor - CC). As participantes foram autorizadas a beber cerca de 279ml (± 42.7ml) de água durante as sessões de exercício. As seguintes variáveis foram avaliadas: temperatura retal (Tre), frequência cardíaca (FC), taxa percepção de esforço (TPE), escala de percepção de esforço para crianças (EPEC), sensação térmica, conforto térmico, irritabilidade, cor e densidade da urinária. ANOVA de um e dois caminhos; ANOVA para medidas repetidas e os testes de Friedman e Wilcoxon (p <0,05) foram realizados com os diferentes tipos de exercícios (EA e EC), e as condições de temperatura (Tn e C) como fatores. Resultados: A análise confirmou semelhantes (p> 0,05) os níveis de hidratação, Tre e UR, no início de cada sessão de exercícios confirmando a linha de base. Os resultados mostraram diferenças entre pré e pós-exercício na Tre (AC: 37,1± 0,2 para 37,7±0,2ºC, e CC: 37,1±0,2 para 37,5±0,2°C) (p=0,001). Não foram encontradas diferenças durante as sessões CTn (p=0,967). Durante as sessões ATn, a Tre diferiu (p = 0,016), apenas no vigésimo minuto (37,1±0,2 para 37,4 ± 0,3). Além disso, não houve diferença (p=1,000) entre as sessões ATn e CTn. No entanto, houve diferença (p = 0,016) comparando a AC e CC, no minuto 35 (AC= 37,6 ± 0,2; CC= 37,4 ± 0,2 °C), e no minuto 40 (AC = 37,7 ± 0,2 e CC= 37,5 ±0,2 °C). O conforto térmico e sensação térmica foram maiores durante as sessões de calor e no exercício aeróbio (p <0,05). Não houve diferença na EPEC e irritabilidade. Conclusão: Em geral, estes resultados concluem que as adolescentes obesas respondem melhor em termos fisiológicos e perceptivos durante o EC em comparação com as sessões de EA. Além disso, os resultados demonstraram que a percepção de esforço, sensação térmica, e conforto térmico conduziu a um aumento significativo do prazer relatado no EA independente da condição térmica. Portanto, o EC pode aumentar o prazer e motivação intrínseca para a atividade física, aumentando a adesão desta população específica. / Introduction: Exercise is well known as one of the most powerful tools to prevent and control obesity. However, the reasons why overweight individuals seem even less willing than normal-weight ones to participate in, and adhere to exercise programs remain largely unknown. One of the hypotheses is that the high rates of dropouts typically found among overweight teenagers might be due to the type of exercise prescribed, and/or compromised thermoregulatory ability. The interaction between exercise and excess body weight would alter some unique variables such as, body temperature, perceived exertion, thermal comfort, and irritability, especially if exercises programs are performed in environments with high temperatures. Aim: This study investigated physiological and perceptual responses in teenager women during concurrent (CE) and aerobic exercise (AE) sessions, under two distinct thermic environmental conditions: artificially heated (Ht) and thermoneutral (Tn). Methods: Twelve obese pubescent girls (12.7 ± 0.6 years, 49.9 ± 3.0% fat) physically active and heat-acclimatized were randomly assigned to participate in four differents sessions, the AE sessions last 40-minutes each and consisted of cycling (60-70% of VO2peak) under two environmental conditions: Aerobic Thermoneutral (ATn) in which the temperature was kept to 22-25°C, and relative humidity between 55-60%; and Aerobic Heated (AHt) in which the temperature was kept between 35-37ºC, and relative humidity between 40-45%. The CE sessions were organized into four periods (10 minutes each) alternating cycling (60-70% VO2peak) and two sets of nine strength exercises [12-15 repetitions at 60-70% of 1-RM]. The CE sessions were also tested under the same above-mentioned environmental conditions (concurrent thermoneutral - CTn and concurrent heated - CHt). Participants were allowed to drink about 279ml (± 42.7ml) of water during the exercise sessions. The following variables were assessed: rectal temperature (Tre), heart rate (HR), rate of perceived exertion (RPE), perceived exertion scale for children (PESC), thermal sensation, thermal comfort, irritability, urine color, and urine specific gravity. One, and two way ANOVAs, repeated measures ANOVA, and Friedman and Wilcoxon tests (p <0.05) were performed using the different types of exercises (AE and CE), and temperature conditions (Tn and Ht) as factors. Results: The analysis confirmed similar (p> 0.05) hydration levels, Tre, and HR at the beginning of each exercise session confirming the baseline. The results showed differences between pre- and post-exercise Tre assessments (AHt: 37.1 ± 0.2 - 37.7 ± 0.2 ºC; and CHt: 37.1 ± 0.2 - 37.5 ± 0.2 °C) (p = 0.001). No differences were found during the CTn sessions (p = 0.967). During the ATn sessions, the Tre differed (p = 0.016) only during the first 20 minutes (37.1 ± 0.2 - 37.4 ± 0.3). Furthermore, no difference (p = 1.000) was found between the ATn and CTn sessions. However, the comparison between AHt and CHt differed (p = 0.016) at the 35 (AHt = 37.6 ± 0.2; and CHt = 37.4 ± 0.2 °C), and 40 minutes (AHt = 37.7 ± 0.2 and CHt = 37.5 ± 0.2 °C). The thermal comfort and thermal sensation were higher during the heated and aerobic sessions (p <0.05). No differences in the PESC, and irritability were found. Conclusion: Overall these findings conclude that overweight teenagers respond physiologically better during CE as compared to AE sessions. In addition, the results demonstrated that perceived exertion, thermal sensation, and thermal comfort led to a significant increase in reported pleasure on AE regardless of environmental condition. Over time, the CE could increase the enjoyment of and intrinsic motivation for physical activity, increasing adherence of this particular population.

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