Acute effects of exercise snacks on postprandial glucose and insulin metabolism in adults with obesity: a systematic review and meta-analysis.

Objective: To quantify the acute effects of brief, frequent interruptions to prolonged sitting ("exercise snacks") on postprandial glucose and insulin in adults with obesity, and to explore potential effect modifiers. Data sources and methods: Following PRISMA 2020, seven sources (PubMed, Web of Science, Cochrane Library, Embase, ClinicalTrials.gov, ICTRP, CINAHL) were searched to July 10, 2025. Randomized crossover or parallel trials in adults with obesity comparing activity breaks with uninterrupted sitting were included. Co-primary outcomes were glucose and insulin incremental area under the curve (iAUC); secondary outcomes were total AUC (tAUC) and mean levels. Random-effects meta-analyses synthesized standardized or mean differences (95% CI); heterogeneity was quantified by I Results: Seventeen trials (261 unique participants; predominantly randomized crossover) were included. Versus uninterrupted sitting, activity breaks reduced glucose iAUC (SMD = -0.49, 95% CI -0.85 to -0.14; I Conclusion: In adults with obesity, interrupting sitting about every ≤30 min with 2-5 min of light-to-moderate walking or simple resistance acutely attenuates postprandial glucose and insulin responses. These findings support exercise "snacks" as a pragmatic behavioral strategy, while longer-term randomized trials are needed to define durability and refine dose parameters. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251144139, Identifier CRD420251144139.