Strength training represents an alternative to endurance training for patients with type 2 diabetes. Little is known about the effect on insulin action and key proteins in skeletal muscle, and the necessary volume of strength training is unknown. A total of 10 type 2 diabetic subjects and 7 healthy men (control subjects) strength-trained one leg three times per week for 6 weeks while the other leg remained untrained. Each session lasted no more than 30 min. After strength training, muscle biopsies were obtained, and an isogly-cemic-hyperinsulinemic clamp combined with arterio-femoral venous catheterization of both legs was carried out. In general, qualitatively similar responses were obtained in both groups. During the clamp, leg blood flow was higher (P < 0.05) in trained versus untrained legs, but despite this, arterio-venous extraction glucose did not decrease in trained legs. Thus, leg glucose clearance was increased in trained legs (P < 0.05) and more than explained by increases in muscle mass. Strength training increased protein content of GLUT4, insulin receptor, protein kinase B-␣/␤, glycogen syn-thase (GS), and GS total activity. In conclusion, we found that strength training for 30 min three times per week increases insulin action in skeletal muscle in both groups. The adaptation is attributable to local contraction mediated mechanisms involving key proteins in the insulin signaling cascade. Diabetes 53:294 –305, 2004 I t is an established finding that aerobic endurance training increases insulin action in patients with type 2 diabetes (1–9), and also that the effect of training is predominantly located to the skeletal muscle (10). Glycemic control also improves along with training (11). Furthermore, with the increased insulin action, the need for insulin to mediate the clearance of a given amount of glucose is lessened. Thus, the need for exogenous insulin or oral hypoglycemic agents is decreased (12). Apart from the beneficial effects on glucose metabolism, physical training also exerts marked improvement on most of the components of the metabolic syndrome (13). Despite the scientific evidence of the therapeutic effect of exercise training, it is a well-known clinical experience that it is often very difficult to engage the patients into taking exercise on a regular basis, and even if one succeeds , the adherence is disappointing. The majority of patients with type 2 diabetes are overweight and have usually been sedentary for the major part of their lives. For many reasons, both psychological and sociological, they are not likely to take up endurance training. Obesity may even be a physical problem in the performance of exercise , especially endurance-type exercises. For patients with type 2 diabetes, resistance training probably represents an attractive exercise modality, but little is known about the overall effect, and the effect in muscle has not been studied. Furthermore, dose-response studies on resistance training effects have not been carried out. To provide support for the recommendations about the type and intensity of effective exercise, we have now carried out a study where we investigated the effect of a very low amount of strength training on insulin action in the skeletal muscle in patients with type 2 diabetes. Based on the sparse literature available on strength training regimens in these patients (14 –19), we used a training program that we a priori considered to be minimally effective. We used a one-legged training protocol, a model that is robust against biological variation and that has previously been used to demonstrate the effect of endurance training on skeletal muscle insulin sensitivity (10). Second, we obtained muscle biopsies from both legs and analyzed these for differences in content and activities of proteins and enzymes that could explain a possible effect of strength training.