Post-meal Exercise and Glycemic Control in Aging

描述(申请人描述)：葡萄糖耐量随着年龄的增长而逐渐下降，代谢弹性的下降主要可归因于衰老的继发性因素，如身体成分的变化和体力活动水平的降低。胰岛素分泌不足也是一个重要因素；然而，由于衰老和停用相关的胰岛素抵抗造成的细胞代偿受损，确实可能加速老年人发生挑战后高血糖以及随后的2型糖尿病和心血管疾病的风险。这项建议的目的是检查不同的运动方案对2型糖尿病高危老年人餐后和24小时血糖控制(使用连续血糖监测系统；CGMS)的影响程度。具体目标是：1)比较传统锻炼的短期效果 在低强度(~3.0Met)下进行45分钟持续步行的条件 上午(TEM)，下午进行相同的条件(TEA)，改善糖耐量受损(IGT)的非活动老年人的餐后血糖控制和24小时血糖控制；2a)比较一种新的“吃和运动”锻炼条件[EM；3顿标准餐后30分钟步行15分钟(~3.0 Mets)]与TEA和TEA对改善这些老年人血糖控制的短期效果；以及2b)在这些老年男性和女性中，确定性别和腹脂对餐后运动相关的餐后和24小时血糖控制改善的影响。虽然餐后锻炼模式已经被用作治疗妊娠期糖尿病的有效策略，但它在细胞功能受损的老年人群中的潜力尚未被研究。较短但更频繁的低强度运动的临床相关性很大，因为老年人更有可能定期进行这种类型的体育活动。考虑到老年人与高血糖相关的额外疾病负担，以及公认的慢性病预防价值，设计在最需要锻炼的人群中令人愉快和有效的锻炼计划对公众健康有巨大的好处。公共卫生相关性：餐后高血糖可能是减缓从糖耐量受损向坦率2型糖尿病和心血管疾病进展的限速因素。餐后锻炼可能是补充内源性胰岛素作用的有效策略，以改善老年人的餐后和24小时血糖控制。较短但更频繁的低强度运动的临床相关性很大，因为老年人更有可能定期进行这种类型的体育活动。考虑到老年人与高血糖相关的额外疾病负担，以及公认的慢性病预防价值，设计在最需要锻炼的人群中令人愉快和有效的锻炼计划对公众健康有巨大的好处。

DESCRIPTION (applicant's description): Glucose tolerance declines progressively with aging, and this decline in metabolic resiliency can be attributed primarily to factors secondary to aging, such as changes in body composition and low levels of physical activity. Insufficient insulin secretion is also an important contributor; however, as impaired ¿-cell compensation to aging- and disuse-related insulin resistance may indeed accelerate the risk of developing post-challenge hyperglycemia and consequent type 2 diabetes and cardiovascular disease in older age. The purpose of this proposal is to examine the extent to which different exercise protocols impact post-prandial and 24-h glycemic control (measured using a continuous glucose monitoring system; CGMS) in older people at risk for type 2 diabetes. Specific aims are: 1) To compare the short-term effectiveness of a traditional exercise condition involving 45 min of sustained walking at lower intensity (~3.0 METs) performed in the morning (TEM), with the same condition performed in the afternoon (TEA) on improvements in postprandial and 24-h glycemic control in inactive older people with impaired glucose tolerance (IGT); 2a) To compare the short-term effectiveness of a novel "Eat and Move" exercise condition [EM; 15 min of walking (~3.0 METs) performed 30 min after each of 3 standard meals] with TEM and TEA on improvements in glycemic control in these same older people; and 2b) To determine the influence of sex and of abdominal fat on post-meal exercise-related improvements in post-prandial and 24-h glycemic control in these older men and women. While a post-meal exercise paradigm has been used as an effective strategy for gestational diabetes, its potential among older populations with compromised ¿-cell function has not been studied. The clinical relevance of shorter, but more frequent, bouts of lower-intensity exercise is substantial as older people are far more likely to engage in that type of physical activity on a regular basis. Given the excess disease burden associated with hyperglycemia in older age, and the recognized value of chronic disease prevention, there are enormous public health benefits to designing exercise programs that are enjoyable and effective within the populations needing them the most. PUBLIC HEALTH RELEVANCE: Post-prandial hyperglycemia may represent the rate-limiting factor in slowing the progression from impaired glucose tolerance toward frank type 2 diabetes and cardiovascular disease. Post-meal exercise may be an effective strategy for supplementing endogenous insulin action for improved post-prandial and 24-h glycemic control in older age. The clinical relevance of shorter, but more frequent, bouts of lower-intensity exercise is substantial as older people are far more likely to engage in that type of physical activity on a regular basis. Given the excess disease burden associated with hyperglycemia in older age, and the recognized value of chronic disease prevention, there are enormous public health benefits to designing exercise programs that are enjoyable and effective within the populations needing them the most.