Discipline of Exercise Science, Murdoch University, Perth, AUSTRALIA.
Faculty of Nutrition and Exercise Physiology, University of Missouri, Columbia, MO.
Med Sci Sports Exerc. 2020 Feb;52(2):323-334. doi: 10.1249/MSS.0000000000002139.
Despite the acknowledgment of exercise as a cornerstone in the management of type 2 diabetes (T2D), the importance of exercise timing has only recently been considered.
This study sought to determine the effect of diurnal exercise timing on glycemic control in individuals enrolled in a 12-wk supervised multimodal exercise training program. A secondary aim was to determine the effect of diurnal exercise timing on the circadian rhythm of wrist skin temperature.
Forty sedentary, overweight adults (mean ± SD, age = 51 ± 13 yr; body mass index = 30.9 ± 4.2 kg·m; women, n = 23) with and without (n = 20) T2D diagnosis were randomly allocated to either a morning (amEX) or an evening (pmEX) exercise training group. The supervised 12-wk (3 d·wk) program, comprised 30 min of moderate-intensity walking and 4 resistance-based exercises (3 sets, 12-18 repetitions each). Glycemic outcomes (glycated hemoglobin, fasting glucose, postprandial glucose) and wrist skin temperature were assessed at baseline and postintervention.
Exercise training improved (main effect of time, all P < 0.01) all glycemic outcomes; however, this was independent of allocation to either the amEX (Hedge's g, 0.23-0.90) or the pmEX (Hedge's g, 0.16-0.90) group. Accordingly, the adopted exercise training program did not alter the circadian rhythm of skin temperature. When only T2D individuals were compared, amEX demonstrated greater effects (all Hedge's g) on glycated hemoglobin (amEX, 0.57; pmEX, 0.32), fasting glucose (amEX, 0.91; pmEX, 0.53), and postprandial glucose (amEX, 1.12; pmEX, 0.71) but was not statistically different.
Twelve weeks of multimodal exercise training improved glycemic control and postprandial glycemic responses in overweight non-T2D and T2D individuals. However, no distinct glycemic benefits or alterations in circadian rhythm were associated with morning versus evening exercise, when performed three times per week in this cohort.
尽管运动已被公认为 2 型糖尿病（T2D）管理的基石，但运动时机的重要性最近才得到关注。
本研究旨在确定在参加 12 周监督下多模式运动训练计划的个体中，日间运动时间对血糖控制的影响。次要目的是确定日间运动时间对腕部皮肤温度昼夜节律的影响。
40 名久坐、超重的成年人（平均 ± 标准差，年龄 = 51 ± 13 岁；体重指数 = 30.9 ± 4.2 kg·m；女性，n = 23），分为有（n = 20）和无（n = 20）T2D 诊断的两组，随机分配至晨练（amEX）或晚间（pmEX）运动训练组。监督的 12 周（每周 3 天）方案包括 30 分钟的中等强度步行和 4 次基于阻力的运动（3 组，每组 12-18 次重复）。在基线和干预后评估血糖指标（糖化血红蛋白、空腹血糖、餐后血糖）和腕部皮肤温度。
运动训练改善了所有血糖指标（时间的主要影响，均 P < 0.01）；然而，这与分配至 amEX（Hedge's g，0.23-0.90）或 pmEX（Hedge's g，0.16-0.90）组无关。因此，所采用的运动训练方案并未改变皮肤温度的昼夜节律。当仅比较 T2D 个体时，amEX 对糖化血红蛋白（amEX，0.57；pmEX，0.32）、空腹血糖（amEX，0.91；pmEX，0.53）和餐后血糖（amEX，1.12；pmEX，0.71）的影响更大（所有 Hedge's g），但无统计学差异。
12 周的多模式运动训练改善了超重非 T2D 和 T2D 个体的血糖控制和餐后血糖反应。然而，在该队列中每周进行三次运动时，晨练与晚间运动之间没有明显的血糖获益或昼夜节律改变。
