JULIET

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 确定增加体力活动(PA)的方法对于控制肥胖症及其共病(包括2型糖尿病)的流行至关重要。由于未知的原因，肥胖后的女性和黑人女性似乎特别容易体重增加。我们目前的RO1研究数据表明，静息能量消耗和燃料利用的内在变化并不能区分肥胖倾向的女性和肥胖抵抗的女性，也不能预测体重增加。相比之下，身为黑人，体力下降，自由生活的PA较低，以及每日总能量消耗较低，这些都是未来体重增加的强烈预测。 扩展我们目前的研究，以检验运动训练改善自由生活PA的有效性，进而改善能量平衡和体重控制。具体地说，我们假设阻力运动训练在以下方面比有氧运动训练和无运动训练更有效：1)增加日常生活中的生理舒适度和自发参与体力活动；2)增加肥胖黑人和白人女性的日常总能量消耗和减肥维持。 肥胖的绝经前黑人和白人妇女将被随机分为单纯节食组、饮食+有氧训练组和饮食+抵抗力运动训练组。在整个18个月的研究中，将提供饮食/行为干预，包括或不包括有氧运动或阻力运动训练。测试将在肥胖状态下进行，大约6个月后在肥胖后正常体重状态下进行，并在减肥维持1年后进行。所有测试都将在严格控制的普通临床研究中心的条件下进行，经过4周的饮食控制能量平衡。身体成分的变化将通过四室模型进行评估，胰岛素抵抗将通过胰岛素改良的、频繁采样的静脉葡萄糖耐量试验进行评估。主要结果将包括运动感知和生理难度的测量(心脏、呼吸、肌电对标准化运动任务的反应)；有氧健身；力量健身(等长测试)；自发自由生活PA、与活动相关的能量消耗、非运动活动热产生和每日总自由生活能量消耗(均来自双标签水)。 这一结果将有助于深入了解不同类型的运动训练的有效性和机制，通过这些训练可以改善身体健康，自发参与日常生活中的体育活动，进而保持减肥，特别是在容易肥胖的黑人女性中。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Identifying ways to increase physical activity (PA) is paramount to controlling the epidemic of obesity and its co-morbidities, including type 2 diabetes. For unknown reasons, post-obese women and black women appear to be especially prone to weight gain. Data from our current RO1 study suggest that inherent variations in resting energy expenditure and fuel utilization do not distinguish obesity-prone from obesity-resistant women or predict weight gain. By contrast, being of black race and having reduced strength, lower free-living PA, and lower total daily energy expenditure are strongly predictive of future weight gain. To extend our current studies in order to examine the effectiveness of exercise training to improve free-living PA and, in turn, energy balance and weight control. Specifically, we hypothesize that resistance exercise training will be more effective than aerobic and no exercise training in 1) increasing the physiologic ease of, and spontaneous engagement in physical activities of daily living, and 2) increasing total daily energy expenditure and weight-loss maintenance of obese black and white women. Obese premenopausal black and white women will be randomized to either diet-only, diet+aerobic or diet+resistance exercise training groups. Diet/behavior intervention, with or without the aerobic or resistance exercise training, will be provided throughout the 18 months of study. Testing will be done in the obese state, ~6 months later in the normal-weight post-obese state, and after 1 year of weight-loss maintenance. All testing will be under tightly controlled General Clinical Research Center conditions following 4 weeks of diet-controlled energy balance. Changes in body composition will be assessed by the 4-compartment model, and insulin resistance by the insulin modified, frequently-sampled intravenous glucose, tolerance test. Major outcomes will include measures of perceived and physiologic difficulty of exercise (cardiac, ventilatory, electromyographic responses to standardized exercise tasks); aerobic fitness; strength fitness (isometric tests); and spontaneous free-living PA, activity-related energy expenditure, non-exercise activity thermaogenesis, and total daily free-living energy expenditure (all derived from doubly labeled water). The results will provide insight into the effectiveness of, and the mechanisms by which, different types of exercise training can improve physical fitness, spontaneous engagement in physical activities of daily living and, in turn, weight-loss maintenance, especially in obesity-prone black women.