Physical activity improves insulin sensitivity and metabolic control in patients with type 2 diabetes. Moreover, regular exercise can reduce systemic levels of immune markers associated with diabetes development. As patients with physical impairments are not able to exercise sufficiently, the aim of this study was to investigate whether high-frequency external muscle stimulation (hfEMS) improves metabolic and immunologic parameters in patients with type 2 diabetes and might therefore serve as complementary lifestyle therapy. Sixteen patients (12 men/4 women, age 57+/-11 years (mean+/-SD); BMI 34.5+/-5.2 kg/m (2); HbA1c 7.4+/-1.1%) on oral antihyperglycaemic therapy were enrolled in this study. After a run-in phase of 2 weeks, every patient received an hfEMS device (HITOP 191, gbo-Medizintechnik AG, Rimbach/Germany) for daily treatment of femoral musculature for 6 weeks. Thereafter, patients were followed up for additional 4 weeks without hfEMS treatment. At each visit, clinical parameters were assessed and blood samples were drawn for metabolic and immunologic parameters. Immune markers (cytokines, chemokines, adipokines and acute-phase proteins) representative for the different arms of the immune system were analysed. hfEMS treatment resulted in significant reductions of body weight (-1.2 kg [-2.7 kg; -0.5 kg]; p<0.05; median [25th percentile; 75th percentile]), BMI (-0.4 kg/m (2) [-0.8 kg/m (2); -0.1 kg/m (2)]; p<0.05) and HbA1c (-0.4% [-0.9%; -0.1%]; p<0.05) which were sustained during the follow-up period. Systemic levels of IL-18 tended to be increased after hfEMS treatment (171 vs. 149 pg/ml; p=0.06), while all other immune markers remained virtually unchanged. Treatment with hfEMS in this first proof-of-principle study has beneficial effects on body weight and improves glycaemic control in patients with type 2 diabetes, which may be associated with changes in subclinical inflammation. Taken together, hfEMS might represent an additional treatment option for patients with type 2 diabetes not being able to exercise.