Exercise-Based Interventions for Metabolic Dysfunction–Associated Fatty Liver Disease: An Umbrella Review of Systematic Reviews and Meta-Analyses

Context The prevalence of metabolic dysfunction–associated fatty liver disease (MAFLD) has increased, and it is emerging as a global health problem. Exercise is the primary treatment, but the ideal prescription remains unclear. Objective The objective of this study was to synthesize the evidence for exercise prescription for MAFLD, encompassing frequency, intensity, duration, type, and outcomes, and to evaluate the methodological rigor and evidence quality. Data Sources Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 6 electronic databases, namely, PubMed, Embase, CINAHL, the Cochrane Library, the Web of Science, and the Joanna Briggs Institute (JBI), were searched for systematic reviews and meta-analyses in April 2024. Backward citation tracking was performed. Data Extraction Data were extracted from exercise prescription data reviews, and the relationships between prescription variables and outcomes were analyzed. AMSTAR-2 and GRADE were used to assess the methodological quality and evidence level. Data Analysis Among the 506 identified studies, 23 systematic reviews were included after excluding irrelevant studies that did not meet the inclusion criteria. Five systematic reviews identified an effective exercise frequency range of 2–5 sessions per week, with the most consistent improvements in total cholesterol observed at 4–5 sessions. Nine reviews addressed moderate to high exercise intensities, while 5 emphasized exercise durations within the 30–60 minute range. Two articles recommended prioritizing a combination of aerobic exercise and resistance training in cases without contraindications. Regarding the literature quality, 82% of the studies were rated as being of low to critically low quality. GRADE assessment indicated that the overall quality of the evidence was low to moderate. Conclusion MAFLD patients may benefit most from exercising 4–5 times per week at moderate to high intensity, particularly through improving lipid profiles. Prioritizing a blend of aerobic and resistance exercises is advisable if there are no contraindications. Optimal session duration falls within the 30–60-minute range, with longer adherence yielding better outcomes. However, more high-quality studies exploring exercise prescription variables and dose–response meta-analyses are needed. Systematic Review Registration PROSPERO registration No. CRD42022344662.