EXERCISE INTENSITY AND POST-PRANDIAL GLUCOSE DISPOSAL IN OBESE ADULTS

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。 在糖耐量受损的个体中，餐后血糖漂移加剧，血液中葡萄糖和胰岛素水平较高的时间较长。越来越多的证据表明，这些加剧的餐后短途旅行与糖尿病和胰岛素抵抗相关的许多并发症，包括动脉粥样硬化、心肌梗死和中风，密切相关，而且可能是预先处理的。运动已被证明可以降低与胰岛素抵抗相关的风险，是减少血糖漂移和提高胰岛素敏感性的有效手段。在这项研究中，我们将研究等卡路里输出的运动强度和由此产生的血糖效应之间的剂量-反应关系，最终目的是确定减少餐后血糖漂移的最低有效运动强度。腹型肥胖受试者(BMI和GT；30，女性腰围和GT；女性为80厘米，男性为&GT；94厘米)将在GCRC上进行5次测试：(1)确定运动强度的基线VO2峰值/LT协议和(4)随机分配的静息和3种不同运动强度(低、中、高强度-运动持续时间将不同，以便在每一次250千卡的运动中卡路里消耗可以保持不变)。在测试2-5期间，75克葡萄糖将在运动开始后1小时内注射。在开始240min的运动后，分别在-30、-20-10、0和5-10分钟间隔采集血样，测定血糖、胰岛素和C-肽。计算血糖和胰岛素的变化率和曲线下面积。最小模型将用于评估葡萄糖处置和胰岛素敏感性，C-肽最小模型将用于评估细胞功能。重复测量的协变量SI的ANCOVA将被用来检查条件之间的差异。

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. In individuals with impaired glucose tolerance, exacerbated post-prandial glycemic excursions occur with higher levels of both glucose and insulin in the blood for longer periods of time. Increasing evidence suggests that these exacerbated post-prandial excursions are closely associated with, and may be pre-disposing for, many of the complications associated with diabetes and insulin resistance, including atherosclerosis, myocardial infarction, and stroke. Exercise has been shown to reduce the risks associated with insulin resistance and is an effective means of reducing glycemic excursions and increasing insulin sensitivity. In the present study, we will examine the dose-response relationship between intensity of exercise at equal caloric output and the resultant glycemic effects, with the ultimate aim of identifying the minimum effective exercise intensity for the reduction of post-prandial glycemic excursions. Abdominally obese subjects (BMI > 30, waist circumference > 80 cm for women and > 94 cm for men) will be tested on the GCRC on 5 occasions: (1) - a baseline VO2 Peak / LT protocol to determine exercise intensities and (4) randomly assigned sessions at rest and at 3 differing exercise intensities (low, moderate, intense - exercise duration will vary so that caloric expenditure can be constant for each exercise session at 250 kcal). During tests 2-5, seventy five grams of glucose will be administered 1 h after the onset of exercise. Blood samples will be collected at -30, -20 -10, 0, and at 5-10 minute intervals after the onset of exercise for 240 min and assayed for glucose, insulin and c-peptide. Glucose and insulin rate of change and area under the curve will be calculated. Minimal modeling will be used to assess glucose disposal and insulin sensitivity, and c-peptide minimal model will be used to evaluate -cell function. Repeated measures ANCOVA with covariate SI will be used to examine differences among conditions.