Dyspnea on Exertion in Obesity: Effects of Exercise Training and Weight Loss

7.项目概要/摘要 肥胖是美国的一个流行病问题，也是美国最重要的健康挑战之一。 21世纪世纪。肥胖的主要后果是死亡率和发病率增加， 心脏病、高血压、糖尿病、睡眠呼吸障碍和代谢综合征。许多 肥胖的成年人经历劳力性呼吸困难并且不能锻炼。因此， 肥胖的成年人不仅是一个重要的和多产的临床问题， 治疗肥胖和肥胖相关的合并症。虽然大多数肥胖的成年人呼吸困难， 一般认为，我们的初步数据挑战了这一传统， 智慧例如，在运动性呼吸困难的女性中，我们发现呼吸的耗氧量 (i.e.,呼吸功）显着增加，并且与劳累性呼吸困难高度相关。照经上所 目前尚不清楚肥胖者劳力性呼吸困难是否是由于心血管失调，其中运动 训练将是非常有益的，或肥胖相关的呼吸力学的变化，其中 在可以忍受运动训练之前，可能需要积极的减肥措施。整体 本申请的目的是调查在其他方面健康的肥胖成年人中是否存在劳力性呼吸困难， 可以通过耐力运动训练来改善（即，增加心血管调节），或通过 体重减轻（即，减少肥胖相关的呼吸限制，特别是， 呼吸）。我们假设，在其他方面健康的肥胖成年人中， 耐力运动训练，因为患有劳力性呼吸困难的肥胖成年人没有被解除， 单独的训练不太可能减少肥胖相关的呼吸限制，特别是 呼吸了相反，我们假设劳力性呼吸困难会随着体重减轻而改善，因为 减肥应该减少肥胖相关的呼吸限制，特别是， 呼吸了在这个应用程序中，我们将利用两个干预措施来调查我们的建议：1）耐力 运动训练而不减轻体重，以及2）减轻体重而不进行耐力运动训练。具体目标： 为了实现总体目标，将检验以下假设：1）耐力运动训练 不会改善患有劳力性呼吸困难的肥胖成人的劳力性呼吸困难;和2）体重减轻， 特别是胸壁脂肪的减少，将改善肥胖成人的劳力性呼吸困难， 用力。我们的长期目标是研究肥胖成人劳力性呼吸困难的机制， 提供了新的临床相关结果，可能会改变介入方法， 预防肥胖，治疗肥胖，降低心脏病，高血压和代谢紊乱的风险。 肥胖患者的综合征。

7. PROJECT SUMMARY/ABSTRACT Obesity is an epidemic problem in the United States and is among the most important health challenges of the 21st Century. The major consequences of obesity are increased rates of mortality and morbidity from heart disease, hypertension, diabetes, sleep-disordered breathing, and the metabolic syndrome. Many obese adults experience exertional dyspnea and are unable to exercise. Therefore, exertional dyspnea in obese adults is not only an important and prolific clinical concern it is an obstacle to the prevention and treatment of obesity and obesity-related comorbidities. Although most obese adults with dyspnea on exertion are generally considered to be deconditioned, our preliminary data challenge this conventional wisdom. For example, in women with dyspnea on exertion, we have found the oxygen cost of breathing (i.e., work of breathing) to be markedly increased and highly associated with exertional dyspnea. Thus, it is presently unclear if exertional dyspnea in obesity is due to cardiovascular deconditioning, in which exercise training would be dramatically beneficial, or to obesity-related changes in respiratory mechanics, in which aggressive weight loss measures may be necessary before exercise training can be tolerated. The overall objective of this application is to investigate whether exertional dyspnea in otherwise healthy obese adults can be ameliorated by endurance exercise training (i.e., increase in cardiovascular conditioning), or by weight loss (i.e., decrease in obesity related-respiratory limitations, specifically, the oxygen cost of breathing). We hypothesize that exertional dyspnea in otherwise healthy obese adults will not improve with endurance exercise training since obese adults with exertional dyspnea are not deconditioned, and exercise training alone is unlikely to decrease obesity-related respiratory limitations, specifically the oxygen cost of breathing. In contrast, we hypothesize that exertional dyspnea will be ameliorated with weight loss, since weight loss should decrease obesity related-respiratory limitations, in particular, the oxygen cost of breathing. In this application, we will utilize two interventions to investigate our proposals: 1) endurance exercise training without weight loss, and 2) weight loss without endurance exercise training. Specific Aims: To accomplish the overall objective, the following hypotheses will be tested: 1) Endurance exercise training will not ameliorate exertional dyspnea in obese adults with dyspnea on exertion; and 2) Weight loss, especially loss of chest wall fat, will ameliorate exertional dyspnea in obese adults with dyspnea on exertion. Our long-term objective is to investigate the mechanism of exertional dyspnea in obese adults and provide novel and clinically relevant results that could potentially alter interventional approaches for preventing obesity, treating obesity, and reducing the risk of heart disease, hypertension, and the metabolic syndrome in obese patients.