STRENGTH TRAINING FOLLOWING GASTRIC BYPASS FOR OBESITY

描述(由申请人提供)： 随着美国肥胖率的急剧上升，越来越多的严重肥胖者正在接受手术治疗，以减轻体重和相关的危险因素。Roux-en-Y胃分流术(RYGB)现在是美国治疗病态肥胖症最常见的手术。然而，RYGB对身体成分和静息能量消耗(REE)的影响知之甚少。本研究的主要目的是确定：1)手术后体重减轻的构成；2)补充蛋白质和力量训练是否可以限制瘦体重和REE的预期减少。研究对象将是体重指数(BMI)在40-56公斤/平方米、年龄在18-49岁之间的病态肥胖女性。和绝经前。除了严重肥胖外，他们将相对健康，并有饮食失败史。除了走路外，他们都是久坐不动的。将有36名研究参与者，在按种族分层后，将被随机分配到三个治疗组(n=12)：1)仅标准术后营养咨询，2)蛋白质补充和标准术后营养咨询，或3)蛋白质补充加力量训练和标准术后营养咨询。蛋白质补充将在手术后不久开始，4周后从每天40g增加到每天80g。力量训练将在术后8周开始，以保证创面的充分愈合，并将包括为期12周的上下半身每周两次的渐进式阻力训练。在隔夜禁食12小时后，将在手术前进行一系列测试测量，并在手术后8周和20周重复进行。这些测试将包括使用水下称重、空气位移(BodPod)、双X射线吸收(DEXA)、磁共振成像(MRI)、同位素稀释(D20)、溴化钠和区域人体测量来测量稀土元素和身体成分。还将对手臂和腿部力量进行评估。此外，还将测量空腹血糖和体重相关激素胰岛素、瘦素、皮质醇和最近发现的生长激素。据预测，在手术后体重大幅下降的过程中，一些可能对骨骼肌和重要器官产生不利影响的瘦组织的损失将通过增加蛋白质摄入量和重量训练来减少。稀土元素和骨密度也可能得到更大程度的保护。血糖和荷尔蒙都应该降低，特别是在运动中，除了生长激素，它应该上升。这一发现将提高对病态肥胖患者手术减肥的理解，并在此类患者的术后护理中具有临床应用价值。

DESCRIPTION (provided by applicant): As the incidence of obesity rises dramatically in the United States, more and more severely obese individuals are undergoing surgical treatment to reduce body weight and associated risk factors. Roux-en-Y gastric bypass (RYGB) is now the most common operation to treat morbid obesity in the US. However, little is known about the effects of RYGB on body composition and resting energy expenditure (REE). The main objectives of this study are to determine: 1) the composition of weight loss following surgery, 2) whether protein supplementation and strength training can limit the expected reduction of lean mass and REE. The study candidates will be morbidly obese women with a body mass index (BMI) of 40-56 kg/m2, be 18 - 49 y.o. and premenopausal. Except for severe obesity, they will be relatively healthy with a history of diet failure. They will be sedentary except for walking. There will be 36 study participants who, after stratifying by race, will be randomly assigned to three treatment groups (n = 12): 1) standard postoperative nutritional counseling only, 2) protein supplementation and standard postoperative nutritional counseling, or 3) protein supplementation plus strength training and standard postoperative nutritional counseling. The protein supplementation will begin shortly after surgery and increase from 40 g/day to 80 g/d at 4 weeks. Strength training will begin 8 weeks postoperation, to allow for adequate wound healing, and will consist of twice weekly progressive resistance training for upper and lower body for a period of 12 weeks. A battery of test measurements following a 12 h overnight fast will be conducted prior to surgery and repeated postoperatively at 8 and 20 weeks. These tests will include measurement of REE and body composition using underwater weighing, air displacement (BODPOD), dual xray absorptiometry (DEXA), magnetic resonance imaging (MRI), isotope dilution (D20), sodium bromide, and regional anthropometrics. There also will be assessments of arm and leg strength. Additionally, there will be measures of fasting glucose and body weight related hormones insulin, leptin, cortisol, and the recently discovered ghrelin. The predictions are that during the dramatic weight loss after surgery, the loss of some lean tissue, which could adversely impact skeletal muscle and vital organs, will be reduced by enhanced protein intake and weight training. There also may be greater conservation of REE and bone density. Plasma glucose and hormones should all decrease, especially with exercise, except for ghrelin, which should increase. The findings should improve understanding of surgical weight loss in morbidly obese patients and have clinical applications in the postoperative care of such patients.