Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO 65201, USA.
Med Sci Sports Exerc. 2012 Feb;44(2):225-31. doi: 10.1249/MSS.0b013e31822ac0c0.
Postprandial glucose (PPG) is an independent predictor of cardiovascular events and death, regardless of diabetes status. Whereas changes in physical activity produce changes in insulin sensitivity, it is not clear whether changes in daily physical activity directly affect PPG in healthy free-living persons.
We used continuous glucose monitors to measure PPG and PPG excursions (ΔPPG, postmeal - premeal blood glucose) at 30-min increments after meals in healthy habitually active volunteers (n = 12, age = 29 ± 1 yr, body mass index = 23.6 ± 0.9 kg·m(-2), VO2max = 53.6 ± 3.0 mL·kg(-1)·min(-1)) during 3 d of habitual (≥10,000 steps per day) and reduced (<5000 steps per day) physical activity. Diets were standardized across monitoring periods, and fasting-state oral glucose tolerance tests (OGTT) were performed on the fourth day of each monitoring period.
During 3 d of reduced physical activity (12,956 ± 769 to 4319 ± 256 steps per day), PPG increased at 30 and 60 min after a meal (6.31 ± 0.19 to 6.68 ± 0.23 mmol·L(-1) and 5.75 ± 0.16 to 6.26 ± 0.28 mmol·L(-1), P < 0.05 relative to corresponding active time point), and ΔPPG increased by 42%, 97%, and 33% at 30, 60, and 90 min after a meal, respectively (P < 0.05). Insulin and C-peptide responses to the OGTT increased after 3 d of reduced activity (P < 0.05), and the glucose response to the OGTT did not change significantly.
Thus, despite evidence of compensatory increases in plasma insulin during an OGTT, ΔPPG assessed by continuous glucose monitoring systems increased markedly during 3 d of reduced physical activity in otherwise healthy free-living individuals. These data indicate that daily physical activity is an important mediator of glycemic control, even among healthy individuals, and reinforce the utility of physical activity in preventing pathologies associated with elevated PPG.
餐后血糖（PPG）是心血管事件和死亡的独立预测因子，与糖尿病状态无关。虽然身体活动的变化会导致胰岛素敏感性的变化，但目前尚不清楚日常身体活动的变化是否会直接影响健康的自由生活人群的 PPG。
我们使用连续血糖监测仪在 3 天的习惯性（每天≥10,000 步）和减少（每天<5,000 步）身体活动期间，在健康的习惯性活跃志愿者（n=12，年龄=29±1 岁，体重指数=23.6±0.9kg·m(-2)，VO2max=53.6±3.0mL·kg(-1)·min(-1)）中测量餐后 30 分钟增量的 PPG 和 PPG 波动（ΔPPG，餐后-餐前血糖）。在监测期间饮食标准化，并且在每个监测期的第四天进行空腹口服葡萄糖耐量试验（OGTT）。
在 3 天减少身体活动期间（每天 12,956±769 至 4319±256 步），餐后 30 和 60 分钟时 PPG 升高（6.31±0.19 至 6.68±0.23mmol·L(-1)和 5.75±0.16 至 6.26±0.28mmol·L(-1)，与相应的活跃时间点相比，P<0.05），并且餐后 30、60 和 90 分钟时ΔPPG 分别增加了 42%、97%和 33%（P<0.05）。OGTT 后胰岛素和 C 肽对 OGTT 的反应增加（P<0.05），而 OGTT 中的葡萄糖反应没有明显变化。
因此，尽管在 OGTT 期间有证据表明血浆胰岛素代偿性增加，但在其他健康的自由生活个体中，连续血糖监测系统评估的 3 天减少身体活动期间，ΔPPG 明显增加。这些数据表明，日常身体活动是血糖控制的重要调节因素，即使在健康个体中也是如此，并强调了身体活动在预防与升高的 PPG 相关的病理中的作用。
