Construction of an “Exercise Snacks” Intervention Program Based on Metabolic Phenotype Stratification for Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease
Objective: To construct an “exercise snacks” intervention program based on metabolic phenotype stratification for patients with metabolic dysfunction-associated steatotic liver disease (MASLD), so as to provide a reference for overcoming the bottleneck of poor exercise adherence and implementing precise exercise management in this population. Methods: Following a prespecified evidence-synthesis protocol—with reproducible eligibility criteria; systematic searches of PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and the Wanfang Data Knowledge Service Platform from inception to June 2025; dual independent study selection; and quality appraisal using AGREE II, AMSTAR 2, and the Cochrane RoB 2 tool—evidence on exercise snacks and exercise intervention for MASLD was retrieved and synthesized. Guided by self-efficacy theory and informed by documented barriers to exercise among patients with MASLD, a draft program was developed and then finalized after two rounds of multidisciplinary panel discussion. Results: The program consisted of five modules: metabolic phenotype assessment and classification, phenotype-matched exercise snack prescriptions, a standardized movement library, a digital support system, and exercise safety monitoring. Based on bioelectrical impedance analysis and transient elastography, patients were classified through an explicit stepwise algorithm into three mutually exclusive metabolic phenotypes—sarcopenic obesity, central obesity, and mixed—and matched with resistance-dominant, aerobic interval-dominant, or balanced exercise snacks prescriptions, each delivered as an initial dose (weeks 1 - 4) progressing to a target dose, with weekly volumes computed as bouts/day × min/bout × 7 days. A movement library containing 20 standardized movements across 3 intensity levels was established, together with a “prompt-action-feedback” digital closed-loop support system, explicit intensity control parameters, safety termination criteria, and a home-based escalation pathway for red-flag symptoms. Conclusion: Grounded in evidence and behavioral theory, the program combines fragmented exercise with metabolic phenotype stratification and is a theory-informed, potentially feasible tool for precise exercise management. Its clinical effectiveness and implementation fidelity remain to be verified in prospective studies.
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