Increasing evidence highlights the efficacy of interruptions in prolonged sitting (i.e., activity/sedentary breaks) for improving cardiometabolic health, but precise conclusions and recommendations regarding the optimal interruption frequency remain poorly defined. This systematic review and meta-analysis aimed to directly compare the effect of different frequencies of interrupting prolonged sitting on cardiometabolic health and to determine potential moderators. Randomized crossover trials with at least two frequency interruptions compared to a prolonged sitting condition were identified via systematic review. We compared the acute effects of high-frequency (≤ 30 min per bout, HF) versus low-frequency (> 30 min per bout, LF) interruption protocols on various cardiometabolic health outcomes via three-level meta-analysis with pooled effects evaluated within a random-effects model and exploration of potential sources of heterogeneity through subgroup analyses. The quality of evidence was assessed using Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. Thirteen studies with 211 participants (24-66 years, 41% female) were included. When comparing HF to LF condition, the HF had a significantly greater reduction in glucose (9 studies [n = 740]; Hedge's g = -0.30, 95% CI [-0.57, -0.03], p = 0.03; I²-level 3 = 42%, PI [-1.01, 0.41]). However, there was no difference in insulin (4 studies [n = 304]; Hedge's g = -0.22, 95% CI [-0.73, 0.29], p = 0.35; I²-level 3 = 52%, PI [-1.18, 0.74]), triglyceride (3 studies [n = 484]; Hedge's g = 0.11, 95% CI [-0.10, 0.30], p = 0.29; I²-level 3 = 0%, PI [-0.10, 0.30]), blood pressure (5 studies [n = 352]; Hedge's g = -0.06, 95% CI [-0.41, 0.28], p = 0.69; I²-level 3 = 35%, PI [-0.81, 0.62]), and superficial femoral flow-mediated dilation (3 studies [n = 98]; Hedge's g = -0.42, 95% CI [-2.43, 1.60], p = 0.47; I²-level 3 = 78%, PI [-4.09, 3.25]) between the two conditions. The quality of evidence was low GRADE for all outcomes. The present study suggests that a higher sedentary interruption frequency might be more efficacious than a lower frequency/higher duration protocol for reducing glucose levels. Based on these findings, interrupting sedentary time at least, every 30 min may be an ideal strategy to improve glucose control.

Keywords: cardiometabolic health; exercise snacks; glucose control; interrupting prolonged sitting; meta‐analysis; prolonged sitting; sedentary behavior; sedentary breaks.

© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

越来越多的证据表明，打断长时间坐着（即进行活动或久坐休息）对改善心血管代谢健康具有有效性，但关于最佳中断频率的确切结论和建议尚不清楚。这项系统综述和元分析旨在直接比较不同频率打断长时间坐着对心血管代谢健康的效应，并确定潜在的影响因素。通过系统回顾识别了至少包含两种不同中断频率与长时间坐着条件对比的随机交叉试验。我们采用三级元分析，通过随机效应模型评估汇总效应并进行亚组分析以探索异质性的潜在来源，比较高频（每段≤30分钟）和低频（每段>30分钟）打断方案对各种心血管代谢健康结果的急性效果。

纳入了13项研究，共有211名参与者（年龄范围：24-66岁，女性占41%）。与低频条件相比，高频条件下血糖降低显著更大（9项研究 [n = 740]; Hedge's g = -0.30, 95% CI [-0.57, -0.03], p = 0.03; I²-level 3 = 42%, PI [-1.01, 0.41]）。然而，在胰岛素 (4项研究 [n = 304]; Hedge's g = -0.22, 95% CI [-0.73, 0.29], p = 0.35; I²-level 3 = 52%, PI [-1.18, 0.74])、甘油三酯 (3项研究 [n = 484]; Hedge's g = 0.11, 95% CI [-0.10, 0.30], p = 0.29; I²-level 3 = 0%, PI [-0.10, 0.30])、血压 (5项研究 [n = 352]; Hedge's g = -0.06, 95% CI [-0.41, 0.28], p = 0.69; I²-level 3 = 35%, PI [-0.81, 0.62]) 和股浅动脉流介导的扩张 (3项研究 [n = 98]; Hedge's g = -0.42, 95% CI [-2.43, 1.60], p = 0.47; I²-level 3 = 78%, PI [-4.09, 3.25]) 等方面，两种条件之间没有差异。所有结果的证据质量均为低等级（GRADE）。本研究提示，较高的久坐中断频率可能比较低的频率/更长的持续时间方案在降低血糖水平方面更为有效。根据这些发现，至少每30分钟打断一次久坐可能是改善血糖控制的理想策略。

关键词：心血管代谢健康；运动零食；血糖控制；打断长时间坐着；元分析；长时间坐着；久坐行为；久坐休息。