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Running for Your Life: Motivational Factors for Increased Physical ActivityFeeser, Kristiana Marie 01 December 2016 (has links)
The purpose of this study was to examine the relationship between message framing and behavioral expectancy in maintenance stage runners. Further, correlational analyses were computed to examine the relationship between level of motivation and Locus of Control (LOC). Motivation and LOC were measured before the participant was presented with positively, negatively, or neutrally framed messages (based on random assignment). Participants then answered a level of behavioral expectancy (i.e., how likely or unlikely they are to engage in this behavior) and an explanation of cognitive evaluation in the form of a qualitative question (why the provided message was persuasive or not). This stage was operationalized as running for at least one year, competing in at least one race per year, and running at least one mile per week. The sample consisted of mTurk (Amazon’s Mechanical Turk) users. Results indicated that the neutral message framing condition was significantly different in terms of behavioral expectancy from that of both the positive and negative message framing conditions. The positive and negative message framing conditions, however, did not result in significant differences in behavioral expectancy. Finally, while Locus of Control and levels of motivation are positively correlated in the literature, there was no significant correlation between these variables in this study. Conclusions from this research can be used to inform future health campaigns directed towards those already engaging in physical activity. Furthermore, results can be used to inform future research on message framing in non-active populations.
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Is the acute neuromuscular fatigue produced during resistance training associated with chronic increases in muscle strength and muscle fiber area?Brandenburg, Jason Peter 25 October 2018 (has links)
The primary objective of the present study was to examine the effects of three resistance
training programs that varied in either inter-set rest interval length or volume of training on
the development of strength and muscle fiber size. Male subjects with a minimum of 1-
year of regular resistance training experience were randomly assigned to one of three, 8-
week training groups. The first set of all three programs was similar in that 10 repetitions
to failure were performed. In program A (n=5) the load (78% 1-RM) remained constant for
all subsequent sets. Program B (n=7) also used a constant load (80% 1-RM), however the
rest interval was reduced from 3 minutes (as in Program A) to 1 minute. Subjects in this
group performed additional sets to equate training volume with Program A. The training
load for Program C (n=7) was progressively reduced (80% to 70% 1-RM) before each
subsequent set to ensure the completion of 10 repetitions. Therefore, the volume
performed was greater than that of Programs A and B. Single arm elbow flexion 1-RM
increased by 12.3 +/- 3.5% in Program A, 16.5 +/-3.5% in Program B, and 14.1 +/- 4.7% in
Program C. Gains in 10-RM equaled 16.3 +/-4.1%, 18.0 +/- 5.0% and 13.9 +/- 3.1% for
Programs A, B and C, respectively. Although these increases in strength were significant
(p<.05), there were no differences in the magnitude of change between the three groups.
Increases in the cross-sectional area of type I and type II muscle fibers were similar after all
three training programs. The second objective of this investigation was to measure the
acute neuromuscular fatigue produced during a single session of each of the training
protocols incorporated in the longitudinal part of this study. Force and IEMG during
maximal isometric voluntary contractions (MVIC) along with blood lactate were assessed
prior to and upon the completion of each protocol. Subjects performed 3 sets of single-arm
elbow flexion to failure using a training load of approximately 77.3% 1-RM in Protocol A.
During Protocol B, subjects utilized the same constant resistance but the rest-intervals
between each set were 1 minute. Protocol C was designed to maintain the repetitions
completed per set at 10 while utilizing 3-minute rest interval. During Protocol C, the load
used during the first set was equal to that used during Protocol A and was then reduced by
about approximately 5% for each of the two subsequent sets. Protocol A and Protocol B
resulted in similar reductions in MVIC, whereas Protocol C (24.8 +/- 7.2%) resulted in a
significantly (p<.05) greater reduction in MVIC than Protocol A (20.2 +/- 7.7%). Protocols
A and B elicited similar reductions in the force-time curve of the MVIC. A significantly
greater reduction in the final 300ms of the force-time curve was observed following
Protocol C (in comparison to Protocol A) (p<.05). There were no significant changes in
IEMG after subjects performed protocols A and B. A significant time effect (with no
interaction effect) in IEMG was observed following the comparison of Protocol A with
Protocol C. Blood lactate increased significantly in response to all three protocols with no
differences between the protocols. The third objective of this study was to compare the
magnitude of resistance training-induced acute fatigue before and after the completion of 8
weeks of resistance training specific to the fatigue protocols used. The magnitude of
resistance training-induced acute neuromuscular fatigue remained unchanged following the
resistance training programs. The results appear to indicate that acute neuromuscular
fatigue produced during resistance training may not be associated with the chronic
increases in muscle strength and size. / Graduate
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Exploration of Heat Strain during Light to Moderate Intensity Exercise throughout PregnancyAkbari, Pegah 26 October 2018 (has links)
Regular physical activity is recommended in healthy pregnancies and has been shown to mitigate adverse pregnancy outcomes. Despite the benefits, many women do not adhere to the recommendations due to concerns of exercise-induced heat stress and the dangers it could pose to the developing fetus. While the majority of the concerns raised are not grounded in evidence, currently there are no studies that directly examine the isolated influence of pregnancy on metabolic heat production resulting from physical activity. Additionally, despite the prevalent use of psycho-physical tools in clinical settings, there is a scarcity of literature exploring the relationship between the physiological and perceptual measures of exercise-induced heat strain in the pregnant population. Therefore, objective one of this thesis was to quantify the heat production resulting from light to moderate physical activity (intensities recommended during pregnancy) throughout gestation. Secondly, in objective two, physiological and perceptual measures of thermal strain were compared and assessed throughout pregnancy. In evaluating the change in heat production resulting from exercise (objective one), 10 non-pregnant control (30±1 yrs; BMI=22.3±0.8 kg/m2) and 10 pregnant (32±1 yrs; pre-pregnancy BMI=22.8±0.8 kg/m2) women performed a seven stage submaximal walking test in a thermal controlled chamber (23ºC). Testing was performed during their 1st (T1, 12-16 wks), 2nd (T2, 24-28 wks) and 3rd (T3, 34-38 wks) trimester of pregnancy while metabolic heat production was measured through indirect calorimetry. To assess the changes in thermal and perceptual strain (objective two), 16 non-pregnant control (32±1 yrs; BMI=22.7±0.7 kg/m2), and 20 pregnant (32±1; pre-pregnancy BMI=23.2±0.6 kg/m2) women underwent a graded walking exercise protocol at T2 and T3. Over the course of this test, heart rate, tympanic temperature (Ttymp), skin temperature (Tskin), rate of perceived exertion (RPE, 20-point scale) and thermal sensation (9-point scale) were assessed. Findings from this thesis show that for the same given progressive exercise test, women in T1 experienced similar metabolic heat production to their non-pregnant counterparts. However, as pregnancy progressed, women exhibited on average, a 7-8% increase in heat production per trimester of pregnancy that can be accounted for by weight gain. Further, at baseline conditions, heart rate responses increased with pregnancy, while Ttymp remained unchanged and Tskin decreased. In response to exercise, the magnitude of change in heart rate, Ttymp and Tskin did not differ between gestational conditions. Finally, a strong correlation was identified between heart rate and RPE throughout pregnancy, while thermal sensation only directly correlated with Ttymp and not Tskin. Overall, the present findings suggest that while the same progressive exercise test results in greater levels of heat production as pregnancy progresses, this is not observed in physiological or perceptual measures of heat strain. Rather, findings of this thesis support the notion of improved thermoregulatory responses to account for the increase in metabolic heat production. Moreover, the present thesis provides support for the use of the RPE and thermal sensation scales as effective psycho-physical tools in the pregnant population under conditions of light to moderate exercise in normothermic conditions.
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Goal-orientations, intrinsic motivation & adherence to regular physical activityMarkland, David January 1993 (has links)
This research has investigated exercise adherence from the perspective of Cognitive Evaluation Theory (CET: Deci & Ryan, 1985a). In particular, the motivational consequences of internally controlling and internally informational modes of behavioural regulation was explored with respect to the kinds of exercise goals that individuals adopt. It was proposed that goals will influence intrinsic motivation for exercise to the extent that they are controlling or informational in nature. The first part of the thesis describes conceptual and operational issues and the development and validation of measures of perceived locus of causality (the Locus of Causality for Exercise Scale: LCE) and participation motives (the Exercise Motivations Inventory: EMI). In addition, the psychometric -integrity of the Intrinsic Motivation Inventory (IMI: McAuley et al., 1989, 1991) was examined. Results suggested that the LCE and the EMI possessed reasonably good factorial and construct validity. However, questions were raised about the theoretical underpinnings and item content of the IMI. The second part of the research involved an intervention in which subjects were trained to set effective, personally-controllable goals for exercise. Results showed that goal-setting training was not superior to an attentioncontrol procedure, with both treatments leading to a significant increase in exercise levels. However, large individual differences were noted in the effects of both treatments. These were explained in terms of Causality Orientations Theory (Deci & Ryan, 1985a), which proposes that people differ in the extent to which they seek to be autonomous or controlled in the regulation of their behaviour. Follow-up analyses supported this interpretation. The results of the research programme suggest that the internally controlling/internally informational distinction is important in the exercise context, but that CET, and the more wide-ranging Self-Determination Theory of which it is a part, suffer from a degree of conceptual confusion and operational difficulties which need to be addressed if progress is to be made in understanding and explaining exercise behaviour.
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A transtheoretical approach to exercise : self-determination, stages of change, processes of change and personal construction of exerciseMullan, Elaine January 1998 (has links)
This research examined the role of motivational cognitions and belief systems in the process of exercise adoption and maintenance. Deci and Ryan (1985,1990) outline a continuum of behavioural regulation that ranges from non-self-determined regulation (external regulation) to completely self-determined regulation (intrinsic regulation). Prochaska and DiClemente (1984) describe five stages of behaviour change that range from no thoughts of changing (precontemplation) to maintenance of change (maintenance). They also outline ten strategies and techniques for encouraging and maintaining change which are known as the processes of change. Kelly (1955, 1963) presents a personal construct theory which maintains that each of us has theories or constructs about people and events which guide beliefs and behaviour. Research, which integrated these concepts, was conducted in three phases. A Behavioural Regulation in Exercise Questionnaire was developed in the first phase of research. Results from the second phase of research revealed that regulation of exercise behaviour was more self-determined in the later than in the earlier stages of change. This highlights the importance of motivational considerations in understanding the change process. Only five of the ten processes of change made a meaningful contribution to differentiation among the stagesi n femalesw hile only three of the processesm ade a meaningfulc ontribution to differentiation among the stages in males. These processes showed moderate to strong correlations with those forms of behavioural regulation that are at least somewhat selfdetermined. In addition, those successfully changing their stage of exercise behaviour over a three month period increased their use of the counter-conditioning process. However, confirmatory factor analysis of the Processes of Change for Exercise Questionnaire brought into question the factorial validity of the measure. The final phase of research examined personal construction of exercise as a function of stage of changea nd self determination for exercise. Those in the maintenance stage of change had strong opinions about and strong preferences for certain modes of exercise, while references to being too serious about exercise were strongest in the preparation and precontemplation stages. The preparation stage was marked by desire for more motivation and push to take more exercise. As self-determination decreased references to lack of time for exercise and a desire to have more motivation or put in more effort increased. This research suggests that conflict between desired self (more active and healthy) and actual self (not the fit and active type) may be greatest in the preparation and action stages of change where the act of exercising is still low in self-determination and not yet reconciled with one's sense of self.
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The Influence of Exercise During Weight Loss on Muscle Remodeling During Colon Cancer Induction In MiceRoubos, Sophia 10 September 2018 (has links)
Background: Diet and exercise have been recommended to reduce the risk of colorectal cancer (CRC) in individuals with obesity. However, the effects of these interventions on muscle remodeling during CRC initiation in individuals who were previously obese is unknown. Since CRC is associated with a high-risk of cachexia, it is important to understand how diet and exercise interventions can impact muscle remodeling in populations at risk of developing CRC-induced cachexia. Our aim was to investigate the effects of weight loss, with or without exercise, on markers of muscle remodeling in a mouse model of CRC. We hypothesized that exercise plus weight loss would increase muscle mass, reduce muscle fibro/fatty tissue, and increase muscle stem/progenitor cell content compared to weight loss alone.
Methods: Mice consumed a high-fat diet (HFD) to induce obesity or a control (CON) diet. Subsequently, mice received injections of azoxymethane (AOM) to induce CRC. Then, weight loss was induced in HFD mice by placing them on the CON diet and those mice either remained sedentary (HFD-SED) or completed a treadmill exercise intervention (HFD-EX).
Results: After 40 weeks, mice were sacrificed and analyzed for markers of muscle remodeling. HFD-SED and HFD-EX showed weight loss and a loss in percent fat mass when looking at changes between sacrifice and before AOM injections (p<0.05 vs. CON). HFD-SED and HFD-EX had increased lean mass (p<0.05 vs. CON), and HFD-EX had increased tibialis anterior (TA) weight (p<0.05 vs. CON). The proportion of medium-sized fibers increased (p<0.05 vs. HFD-SED and CON) in HFD-EX, but there were no differences in overall cross-sectional area, myonuclei per fiber, or myonuclear domain. HFD-SED had increased fibrosis (p<0.05 vs. HFD-EX and CON) and adiposity (p<0.05 vs. CON). The number of committed (Pax7+MyoD+) satellite cells (SCs) and FAPs was greater in HFD-EX (p<0.05 vs. CON). There were no differences in uncommitted (Pax7+MyoD-) or differentiated (Pax7-MyoD+) SCs. Additionally, nuclear p-NF-κB was reduced following exercise (p<0.05), specifically in the interstitium with a significant decrease in the number of interstitial p-NF-κB cells in the HFD-EX group (p<0.05 vs. CON and HFD-SED).
Conclusions: Findings suggest that a HFD, followed by weight loss with exercise, can reduce fibrotic and fatty degeneration of the muscle and improve markers of muscle remodeling. These findings provide the rationale to further examine exercise interventions for maintaining muscle quality during weight loss interventions to reduce CRC-induced cachexia.
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Tolerância ao esforço físico e função cardíaca em diferentes períodos pós-indução de estenose aórtica em ratosMendes, Olga de Castro [UNESP] 28 February 2008 (has links) (PDF)
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mendes_oc_me_botfm.pdf: 471774 bytes, checksum: 85d9ae9190c29d29bbfa5997d937273b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Em razão de, em estudos que analisam a relação remodelação cardíaca e estenose aórtica supravalvar: ser importante a detecção precoce da disfunção ventricular; o método hemodinâmico ser ideal para detecção da disfunção, porém inadequado para estudos seqüenciais; a taquipnéia manifestar-se, geralmente, quando há deterioração cardíaca grave e não estar estabelecida a relação entre a capacidade funcional e a função ventricular, torna-se necessário identificar se o(s) primeiro(s) sinal(is) de intolerância ao esforço físico está(ão) relacionado(s) a disfunção ventricular. Assim, este trabalho tem como objetivos avaliar em diferentes períodos, 3, 6, 12 e 18 semanas, após indução de estenose aórtica supravalvar em ratos a: 1) função do ventrículo esquerdo em repouso e as alterações morfológicas cardíacas por meio do ecocardiograma; 2) tolerância ao esforço físico, em teste incremental em esteira; 3) relação entre a tolerância ao esforço físico e a função cardíaca determinada em repouso. Foram utilizados 37 ratos Wistar, jovens, machos divididos em dois grupos: controle operado (GC, n=13) e estenose aórtica supravalvar (GEAo, n=24). O GEAo foi submetido a cirurgia com implantação de um clipe na artéria aorta para a indução da estenose aórtica supravalvar. O GC foi submetido à mesma cirurgia, porém sem a implantação do clipe. Os animais foram mantidos com água e ração e ad libitum, em ambiente com temperatura controlada a 23°C e ciclo de luz invertido. Todos os procedimentos foram realizados no ciclo escuro, com o auxílio de iluminação fluorescente vermelha, cuja emissão de onda, por ser longa, não é percebida pelos animais. Dos 24 ratos do grupo estenose aórtica (GEAo), 10 morreram e dois apresentaram sinais de insuficiência cardíaca ao final do experimento, taquipnéia associada a derrame pleural... / Considering that, in studies analyzing the relationship between cardiac remodeling and supravalvar aortic stenosis, the early detection of ventricular dysfunction is important, the hemodynamic method is ideal to detect such dysfunction although it is inadequate for sequential studies, tachypnea is generally manifested when severe cardiac deterioration exists and that the relationship between functional capacity and ventricular function has not been established, it is necessary to identify whether the first sign(s) of exercise intolerance is(are) related to ventricular dysfunction. Hence, this study aimed at evaluating, in different periods - 3, 6, 12 and 18 weeks - after the induction of supravalvar aortic stenosis in rats, the following aspects: 1) function of the left ventricle at rest and cardiac morphological alterations by means of an echocardiogram; 2) exercise tolerance during an incremental test on a treadmill; 3) relationship between exercise tolerance and cardiac function determined at rest. Thirty-seven young male Wistar rats were used. The animals were separated into two groups: operated control (CG, n=13) and supravalvar aortic stenosis (GEAo, n=24). GEAo was submitted to surgery with the implantation of a clip on the aorta artery for induction of supravalvar aortic stenosis. GC was submitted to the same type of surgery although without clip implantation. The animals were given water and chow ad libitum and maintained in a controlledtemperature environment at 23°C and an inverted light-dark cycle. All the procedures were performed in the dark cycle by using red fluorescent illumination, whose long wave emission is not perceived by the animals. Of the 24 rats in the GEAo ten died and two presented signs of cardiac insufficiency at the end of the experiment, tachypnea associated with pleural stroke, thrombus in the left atrium and hypertrophia in the right ventricle, thus... (Complete abstract click electronic access below)
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Tolerância ao esforço físico e função cardíaca em diferentes períodos pós-indução de estenose aórtica em ratos /Mendes, Olga de Castro. January 2008 (has links)
Resumo: Em razão de, em estudos que analisam a relação remodelação cardíaca e estenose aórtica supravalvar: ser importante a detecção precoce da disfunção ventricular; o método hemodinâmico ser ideal para detecção da disfunção, porém inadequado para estudos seqüenciais; a taquipnéia manifestar-se, geralmente, quando há deterioração cardíaca grave e não estar estabelecida a relação entre a capacidade funcional e a função ventricular, torna-se necessário identificar se o(s) primeiro(s) sinal(is) de intolerância ao esforço físico está(ão) relacionado(s) a disfunção ventricular. Assim, este trabalho tem como objetivos avaliar em diferentes períodos, 3, 6, 12 e 18 semanas, após indução de estenose aórtica supravalvar em ratos a: 1) função do ventrículo esquerdo em repouso e as alterações morfológicas cardíacas por meio do ecocardiograma; 2) tolerância ao esforço físico, em teste incremental em esteira; 3) relação entre a tolerância ao esforço físico e a função cardíaca determinada em repouso. Foram utilizados 37 ratos Wistar, jovens, machos divididos em dois grupos: controle operado (GC, n=13) e estenose aórtica supravalvar (GEAo, n=24). O GEAo foi submetido a cirurgia com implantação de um clipe na artéria aorta para a indução da estenose aórtica supravalvar. O GC foi submetido à mesma cirurgia, porém sem a implantação do clipe. Os animais foram mantidos com água e ração e ad libitum, em ambiente com temperatura controlada a 23°C e ciclo de luz invertido. Todos os procedimentos foram realizados no ciclo escuro, com o auxílio de iluminação fluorescente vermelha, cuja emissão de onda, por ser longa, não é percebida pelos animais. Dos 24 ratos do grupo estenose aórtica (GEAo), 10 morreram e dois apresentaram sinais de insuficiência cardíaca ao final do experimento, taquipnéia associada a derrame pleural... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Considering that, in studies analyzing the relationship between cardiac remodeling and supravalvar aortic stenosis, the early detection of ventricular dysfunction is important, the hemodynamic method is ideal to detect such dysfunction although it is inadequate for sequential studies, tachypnea is generally manifested when severe cardiac deterioration exists and that the relationship between functional capacity and ventricular function has not been established, it is necessary to identify whether the first sign(s) of exercise intolerance is(are) related to ventricular dysfunction. Hence, this study aimed at evaluating, in different periods - 3, 6, 12 and 18 weeks - after the induction of supravalvar aortic stenosis in rats, the following aspects: 1) function of the left ventricle at rest and cardiac morphological alterations by means of an echocardiogram; 2) exercise tolerance during an incremental test on a treadmill; 3) relationship between exercise tolerance and cardiac function determined at rest. Thirty-seven young male Wistar rats were used. The animals were separated into two groups: operated control (CG, n=13) and supravalvar aortic stenosis (GEAo, n=24). GEAo was submitted to surgery with the implantation of a clip on the aorta artery for induction of supravalvar aortic stenosis. GC was submitted to the same type of surgery although without clip implantation. The animals were given water and chow ad libitum and maintained in a controlledtemperature environment at 23°C and an inverted light-dark cycle. All the procedures were performed in the dark cycle by using red fluorescent illumination, whose long wave emission is not perceived by the animals. Of the 24 rats in the GEAo ten died and two presented signs of cardiac insufficiency at the end of the experiment, tachypnea associated with pleural stroke, thrombus in the left atrium and hypertrophia in the right ventricle, thus... (Complete abstract click electronic access below) / Orientador: Antônio Carlos Cicogna / Coorientador: Katashi Okoshi / Banca: Leonardo Antonio Mamede Zornoff / Banca: Vilmar Baldissera / Mestre
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Efeito da SuplementaÃÃo com Alanil-Glutamina nas AlteraÃÃes da Permeabilidade Intestinal em Ratos Treinados Submetidos a um ExercÃcio Prolongado e Exaustivo de NataÃÃoAntonio Klingem Leite de Freitas 09 August 2013 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O exercÃcio prolongado e exaustivo induz uma disfunÃÃo da barreira intestinal. VÃrios estudos mostram que a suplementaÃÃo com alanil-glutamina (A/G) melhora a proliferaÃÃo das cÃlulas intestinais e absorÃÃo de eletrÃlitos. O objetivo deste trabalho foi investigar o efeito da suplementaÃÃo com A/G na permeabilidade intestinal em ratos treinados apÃs um exercÃcio prolongado e exaustivo de nataÃÃo. Utilizamos ratos Wistar, divididos em sete grupos: 1) SedentÃrio (S); 2) SedentÃrio A/G (S-A/G); 3) Treinado (T); 4) Treinado A/G (T-A/G); 5) ExaustÃo (E); 6) ExaustÃo A/G (E-A/G) e 7) Recuperado (R). Os animais dos grupos suplementados receberam o dipeptÃdeo A/G. Os animais foram treinados durante 12 semanas de nataÃÃo. Na metodologia realizamos anÃlises bioquÃmicas de pH, pCO2, pO2, SO2, excesso de bases (BE), pelo mÃtodo de gasometria e lactato e glicose. Analisamos a transcriÃÃo das junÃÃes firmes: ZO-1, Ocludina, Claudina-2 e PEPT-1 atravÃs de RT-PCR. A anÃlise da permeabilidade intestinal foi realizada pelo mÃtodo da ingestÃo de Lactulose/Manitol (L/M). Fizemos tambÃm anÃlise histolÃgica do duodeno, jejuno e Ãleo. O presente estudo foi aprovado pela CEPA-UFC, em protocolo de N 13/13. Nossos resultados mostraram que pCO2 e SO2 foram aumentados nos grupos E e E-A/G, mas houve queda nos parÃmetros de pH e BE para estes mesmos grupos. Encontramos queda dos Ãndices de glicose e aumento das concentraÃÃes de lactato. Houve aumento significativo no percentual de excreÃÃo de lactulose nos grupos E e E-A/G em relaÃÃo ao grupo S. Houve, no entanto, queda da excreÃÃo de lactulose com diferenÃa estatÃstica entre os grupos E e E-A/G, mostrando proteÃÃo da A/G frente ao aumento da permeabilidade intestinal promovida pelo exercÃcio exaustivo. O percentual de excreÃÃo do manitol foi aumentado nos grupos E e E-A/G em relaÃÃo ao grupo S. Entretanto, na anÃlise da relaÃÃo da permeabilidade dos dois carboidratos L/M observamos um aumento significativo no grupo E em relaÃÃo ao grupo S. Contudo, houve diferenÃa significativa entre os grupos E e E-A/G mostrando que a A/G conseguiu reverter os efeitos da atividade exaustiva na permeabilidade intestinal. Observamos aumento da ZO-1 e ocludina nos grupos S-A/G e T em relaÃÃo a S. Houve tambÃm aumento de ZO-1 no grupo E em relaÃÃo ao S. PorÃm, a A/G reverteu à transcriÃÃo destas junÃÃes firmes nos grupos T-A/G e E-A/G. A transcriÃÃo de claudina-2 foi reduzida no grupo S-A/G, mas obtivemos um aumento no grupo E em relaÃÃo ao S e uma diminuiÃÃo de E-A/G em relaÃÃo ao E. Em relaÃÃo ao PEPT-1, observamos aumento da transcriÃÃo nos grupos T e E em relaÃÃo ao S. Contudo, a A/G reverteu à transcriÃÃo deste peptÃdeo no grupo E-A/G em relaÃÃo ao E. Numa anÃlise de 72 horas apÃs o teste de exaustÃo encontramos valores para a permeabilidade intestinal similares aos grupos sedentÃrios. ConcluÃmos que o exercÃcio prolongado e exaustivo alterou a permeabilidade intestinal e a suplementaÃÃo crÃnica com alanil-glutamina teve efeito protetor contra este aumento. O possÃvel mecanismo da A/G no processo estudado refere-se a processos mecÃnicos de interaÃÃo cÃlula-cÃlula (ZO-1 e ocludina) e/ou eletrolÃticos (claudina-2). / The prolonged and exhaustive exercise induces intestinal barrier dysfunction. Several studies show that supplementation with alanyl-glutamine (A/G) improves the cell proliferation intestinal and electrolyte absorption. The aim of our study was to investigate the effect of supplementation with A/G in the intestinal permeability in rats trained after prolonged exercise and exhaustive swimming. We used Wistar rats that were divided into seven groups: 1) Sedentary (S); 2) Sedentary A/G (S-A/G); 3) Trained (T); 4) Trained A/G (T-A/G); 5) Exhaustion (E); 6) Exhaustion A/G (E-A/G); 7) Recovered (R). The animal supplemented groups received the dipeptide A/G. The animals were trained for twelve weeks. In the methodology we performed biochemical analysis of pH, pCO2, pO2, SO2, and bases excess (BE), by the method of gas analysis and lactate and glucose. We analyzed the transcription of tight junctions: ZO-1, Occludin, Claudin-2 and PEPT-1 by RT-PCR. The analysis of intestinal permeability was performed by the method of the ingestion of lactulose/mannitol (L/M). We also performed histological analysis of the duodenum, jejunum and ileum. This study was approved by the CEPA-UFC on Protocol N 13/2013. Our results showed that SO2 and pCO2 were higher in groups E and E-A/G, but decreased the parameters pH and BE for these same groups. We found falling glucose levels and increased concentrations of lactate. A significant increase in the percentage of excretion of lactulose in groups E and E-A/G than in group S. There was, however, fall of excretion of lactulose with statistical difference between groups E and E-A/G, showing protection against the alanyl-glutamine increased intestinal permeability promoted by exhaustive exercise. The percentage of excretion of mannitol was increased in groups E and E-A/G than in group S. However, in the analysis of the excretion of both carbohydrates lactulose/mannitol we observed a significant increase in group E than in group S. However, there was significant difference between groups E and E-A/G showing that Ala/Gln was able to reverse the effects of exhaustive activity in intestinal permeability. We observed an increase in ZO-1 and occludin in groups S-A/G and T with respect to S. There was also an increase of ZO-1 in the E group compared to S. However, Ala/Gln reversed the transcription of these tight junctions in groups T-A/G and E-A/G. Transcription of claudin-2 was reduced in the S-A/G, but we obtained and increase in the E group compared to a decrease of S and E-A/G against E. Regarding the PET-1 we showed increased transcription in groups T and E in relation to S. However, the Ala/Gln reversed the transcript of this dipeptide in group E-A/G with respect to E. An analysis 72 hours after the exhaustion test values found for intestinal permeability similar to sedentary group. The prolonged and exhaustive exercise altered intestinal permeability and chronic supplementation with Ala/Gln was protective against the increase. The possible mechanism of Ala/Gln refers to mechanical processes of cell-to-cell interaction (occludin and ZO-1) and/or electrolytic (claudin-2).
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Normative isokinetic torque values for rehabilitation in South AfricaLategan, Leon 14 March 2012 (has links)
D.Phil. / The goal of effective rehabilitation should always be to restore "normal" function if possible. What is "normal" function? Although many subjective definitions may describe what is "normal", it is the search for objective criteria of what constitutes "normality" that inspires exercise scientists worldwide! The primary aim of this study was to establish normative isokinetic torque values in young males, for rehabilitation purposes in South Africa. Four hundred and forty four (444) healthy male subjects participated in the study. A Cybex 340 isokinetic dynamometer was used to measure peak torque, using a quantitative experimental design. No correction was made for the effects of gravity. The following movement patterns were included: ankle plantar/dorsiflexion, knee flexion/extension, shoulder external/internal rotation, shoulder horizontal abduction/adduction, shoulder flexion/extension, elbow flexion/extension (using two different grip positions), and forearm pronation/supination. Descriptive statistics together with percentile scaling were used to develop normative values for the movement patterns studied. Normative values were presented in relative terms and expressed as a percentage in terms of Nm torque per kg body mass (% BM). In addition to the relative isokinetic torque values, the agonisUantagonist ratios were also ~xpressed as a percentage. The percentile scales were also included to be used by clinicians involved in talent identification programmes and the screening of elite athletes. To conclude, normative isokinetic values were de'leloped for young South African males. To enable subjects with large variations in body weight to utilize these norms, they were expressed in relative terms (% BM) instead of absolute terms (Nm). The possible benefit of the study was that population-specific and objective normative values were established for rehabilitation purposes and for use in sport science programs.
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