The purpose of this investigation was to compare the frequencies of normal and abnormal findings from exercise electrocardiography (ECG) and post-exercise echocardiography (ECHO) studies in a series of hypertensive and normotensive individuals who underwent diagnostic testing. Data for the ECG and ECHO variables were obtained simultaneously in association with treadmill exercise studies. Eighty consecutive cases were included in this retrospective study. Records were excluded if patients had: history of myocardial infarction; valvular heart disease; ECG evidence of abnormal Q waves, left ventricular hypertrophy (LVH) with abnormal ST/T wave pattern, or left bundle branch block (LBBB); medications that would alter blood pressure responses or ECG interpretation; technically uninterpretable records; or failure to attain 85% of age-adjusted maximal heart rates in the exercise tests. Subjects were defined as hypertensive (HYP) if any one of the following criteria were met: 1) SBP ≥ 140 mmHg or DBP ≥ 90 mmHg; 2) current use of antihypertensive medications; or 3) history of hypertension. Normotensive subjects (NORM) were defined as absence of the above criteria. In each test, ECG data were taken at peak exercise, and ECHO data were taken immediately post-exercise (~ 45 sec). The ECG response was considered abnormal if the ST shifted ≥ 0.1 mV from baseline at J₆₀ while the ECHO response was considered abnormal when new or worsening of pre-existing wall motion abnormalities was observed. Chi square analysis demonstrated that high blood pressure status Significantly increased the frequency of clinically abnormal findings with ECHO (X²=9.15; p ≤ 0.01). This was not the case for exercise ECG (X²=2.12; p > 0.05). However, there waS no Significant difference in the frequency of normal findings when comparing the two testing methods for both subject groups. These results indicate that resting blood pressure status may influence the rate of occurrence of abnormal vs normal ECG and ECHO findings; these data warrant further evaluation studies with invasive criterion measures of CAD status. / Master of Science

Background: Recent evidence suggests weight loss is not necessary to reduce obesity related co-morbidities. The principal finding within these reports is based on examination of group mean values. Accordingly, it is possible that within a given group, the subjects who failed to lose weight did not experience any health improvement, a finding masked by the exaggerated improvement in those who did lose weight. We sought to determine whether a gradient exists between the inter-individual change in bodyweight and corresponding changes in body composition and metabolic risk factors in response to minimal or no weight loss. Methods: Total adipose tissue (AT) and skeletal muscle (SM) were determined by magnetic resonance imaging (MRI) in 46 men and 42 women participating in lifestyle-based programs designed to reduce obesity and related metabolic risk factors. Visceral AT (VAT) and abdominal subcutaneous AT (ASAT) were calculated from a single image at the L4-L5 inter-vertebral space. Glucose uptake was calculated using a hyperinsulinemic-euglycemic clamp procedure. Blood pressure (BP) was determined using an electronic cuff or manually using standard procedures. Waist circumference (WC) was taken at the level of the last rib. Results: Bodyweight did not change in men or women (p>0.10). Collapsed across gender, with the exception of ASAT, SM, and systolic BP, all other anthropometric, body composition, and metabolic risk factor measures improved significantly following treatment (p<0.05). With few exceptions, regression analysis revealed that changes in bodyweight or WC were not associated with corresponding changes in body composition measures or metabolic risk factors (p>0.05). To further consider whether a gradient existed between weight change or WC change on body composition and metabolic risk factors, subjects were cross-classified according to their level of weight/waist change (tertiles) and their respective change in either body composition or metabolic risk factor. Neither weight nor WC change tertile was related to any body composition or metabolic risk factor in a gradient fashion (p>0.05). Conclusion: These findings reinforce and extend the observation that independent of gender, lifestyle-based interventions are associated with reductions in obesity and related metabolic risk factors despite minimal or no weight loss. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-29 13:18:27.916

Made available in DSpace on 2016-06-02T19:22:50Z (GMT). No. of bitstreams: 1 2189.pdf: 840243 bytes, checksum: df5c31ed96eff502c06d8ea77cffe86d (MD5) Previous issue date: 2008-06-27 / Financiadora de Estudos e Projetos / The inability to oxidize fat is a key factor in the etiology of obesity. However, improved performance and VO2max resulting from physical training leads to increased rates of oxidation of fats. Although, there is still a lack of information about the intensity of exercise can interfere with metabolism of carbohydrates and lipids in obese women during a session of exercise and its recovery, because only in an experimental study there is a negative relationship of obesity on the reinstatement of power after a year. Therefore, this study aims to assess the behavior of the metabolism of carbohydrates and lipids in moderately obese women on a test of acute exercise effects on the intensity of ventilatory threshold and the recovery period, in the stage of pre-and post-training physical. This study had the participation of seven women slightly obese (BMI=4.03 kg/m2), with an average age of 43.0 ± 4.0 years, 163 ± 0.2±33.59 cm and previously sedentary who were submitted to the ergospirometry acute test before and after 16 weeks of training in the intensity of ventilatory threshold. During the test respiratory quotient was evaluated to determine the fats and carbohydrates oxidation during exercise and recovery period. The results found that the volunteers used predominantly the energy that comes from carbohydrates during the session of exercise (67.64% and 69.35% of the total spent provided pre-and post-training, respectively). During recovery the percentage of the fats contribution increase of (46.52% of the total oxidized) to the total energy generated, which discreetly marked with training (53.48% of the total oxidized). Based on the findings was observed that the metabolism of carbohydrates provides the muscle contraction support during the exercise in the intensity of ventilatory threshold and that the recovery period lipid metabolism is the counterpart to repay the body stores energy in obese women. / A inabilidade de oxidar gorduras é um fator chave na etiologia da obesidade. No entanto, a melhoria de performance e do VO2max advinda do treinamento físico leva a um aumento das taxas de oxidação de gorduras. Porém, ainda faltam esclarecimentos sobre como a intensidade do exercício pode interferir no metabolismo de carboidratos e de lipídeos de mulheres obesas durante uma sessão de exercício e a sua recuperação, já que apenas em estudo experimental observa-se a relação negativa da obesidade sobre a reposição da energia após um exercício. Sendo assim, o objetivo do presente estudo é de verificar o comportamento do metabolismo de carboidratos e de lipídeos de mulheres moderadamente obesas sobre efeito de um teste agudo de exercício na intensidade do limiar ventilatório e o seu período de recuperação, na condição pré e pós-treinamento físico. Para tanto, o estudo contou com a participação de sete mulheres levemente obesas (IMC=33,59 ± 4,03 Kg/m2), com média de idade de 43,0 ± 4,0 anos, 163 ± 0,2 cm e previamente sedentárias que foram submetidas ao teste agudo de ergoespirometria, no inicio e após transcorridas 16 semanas de treinamento na intensidade do limiar ventilatório. Durante o teste foi avaliado o quociente respiratório para determinação da oxidação de gorduras e de carboidratos durante o exercício e o seu período de recuperação. Com base nos resultados obtidos verificou-se que as voluntárias utilizam predominantemente a energia que advém de carboidratos durante a sessão de exercício (67,64 % e 69,35 % do total oxidado na condição pré e pós-treinamento, respectivamente). Durante a recuperação as gorduras aumentam o percentual de contribuição (46,52 % do total oxidado) para o total de energia gerada, condição discretamente acentuada com o treinamento (53,48 % do total oxidado). Com base nos achados acredita-se que o metabolismo de carboidratos oferece suporte para a contração muscular durante o exercício físico na intensidade do limiar ventilatório e que no período de recuperação o metabolismo lipídico faz a contrapartida para reposição dos estoques de energia corporal em mulheres obesas.