BACKGROUND Prolonged sitting is common in older adults and is associated with insulin resistance and poor cardiometabolic health. We investigate whether breaking prolonged sitting with regular short bouts of standing or light walking improves postprandial metabolism in older white European and South Asian adults and whether effects are modified by ethnic group. METHODS Thirty South Asian (15 women) and 30 white European (14 women) older adults (aged 65-79 years) undertook three experimental conditions in random order. (a) Prolonged sitting: continuous sitting during an observation period if 7.5 hours consuming two standardized mixed meals. (b) Standing breaks: sitting interrupted with 5 minutes of standing every 30 minutes (accumulating 60 minutes of standing over the observation period). (c) Walking breaks: sitting interrupted with 5 minutes of self-paced light walking every 30 minutes (accumulating 60 minutes of walking). Blood samples (glucose, insulin, triglycerides) and blood pressure were sampled regularly throughout each condition. RESULTS Compared with prolonged sitting, walking breaks lowered postprandial insulin by 16.3 mU/L, (95% CI: 19.7, 22.0) with greater reductions (p = .029) seen in South Asians (22.4 mU/L; 12.4, 32.4) than white Europeans (10.3 mU/L; 5.9, 14.7). Glucose (0.3 mmol/L; 0.1, 0.5) and blood pressure (4 mm Hg; 2, 6), but not triglycerides, were lower with walking breaks, with no ethnic differences. Standing breaks did not improve any outcome. CONCLUSIONS Breaking prolonged sitting with short bouts of light walking, but not standing, resulted in clinically meaningful improvements in markers of metabolic health in older adults, with South Asians gaining a greater reduction in postprandial insulin. TRIAL REGISTRATION NCT02453204.

中文翻译：

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在南亚老年人和白人欧洲人中，站立或轻度走路时长时间坐着休息所产生的代谢作用：一项随机急性研究。

背景技术长时间坐着在老年人中很常见，并且与胰岛素抵抗和不良的心脏代谢健康有关。我们调查了长时间坐着休息，定期站立或轻度步行可以改善老年白人欧洲和南亚成年人的餐后新陈代谢，以及是否通过种族改变了这种影响。方法30名南亚人（15名妇女）和30名欧洲白人（14名妇女）老年人（65-79岁）以随机顺序进行了三种实验条件。（a）长时间坐着：如果在7.5个小时内进食两顿标准混合餐，则在观察期内连续坐着。（b）休息：每30分钟休息5分钟（在观察期内累计站立60分钟）。（c）步行休息：坐姿每30分钟中断5分钟的自定步调灯光（累计行走60分钟）。在每种情况下，定期采集血样（葡萄糖，胰岛素，甘油三酸酯）和血压。结果与长时间坐着相比，步行休息可使餐后胰岛素降低16.3 mU / L，（95％CI：19.7，22.0），与南亚人相比，降低幅度更大（p = .029）（22.4 mU / L; 12.4，32.4）欧洲白人（10.3 mU / L; 5.9，14.7）。步行休息时，血糖（0.3 mmol / L； 0.1、0.5）和血压（4 mm Hg； 2、6）较低，而甘油三酸酯则较低，没有种族差异。站立休息并没有改善任何结果。结论长时间的休息会导致短暂的一阵轻步走路，但不能站立，导致老年人代谢健康指标的临床意义显着改善，而南亚人餐后胰岛素的减少幅度更大。试用注册NCT02453204。