Effects of resistance training in adults with type-2 diabetes mellitus: a narrative review of randomised controlled trials

Background: Resistance training has been proposed as an effective non-pharmacological intervention for managing type-2 diabetes mellitus (T2DM). This review examines the effects of resistance training on metabolic parameters, muscle strength, and physical function in adults with T2DM.Methods: A structured literature search was conducted in ScienceDirect, PubMed, and Google Scholar in accordance with PRISMA guidelines. Randomised controlled trials investigating resistance training interventions in adults with T2DM were included. Although a systematic search strategy was applied, findings were synthesised narratively due to heterogeneity in outcomes and limited data suitable for quantitative pooling.Results: Five randomised controlled trials met the eligibility criteria. Resistance training interventions ranged from 15–85% of one-repetition maximum (1RM), performed three times per week for 40–60 minutes. Across studies, resistance training consistently improved muscle strength and physical function. However, findings related to metabolic parameters were inconsistent. Improvements in HbA1c and fasting glucose appeared dependent on baseline glycaemic status, intervention duration, and the presence of co-interventions such as dietary modification.Conclusion: Resistance training reliably enhances muscle strength and functional performance in adults with T2DM, while its effects on glycaemic control remain variable. Given the narrative nature of the synthesis and heterogeneity of included studies, conclusions regarding metabolic outcomes should be interpreted with caution. Future research employing quantitative synthesis is required to clarify clinical significance.