Effects of acute exercise on pancreatic endocrine function in subjects with type 2 diabetes.

We determined the effects of exercise on pancreatic endocrine responses to metabolic stimuli in subjects with type 2 diabetes (T2D) and examined the influence of subjects' diabetic status. Fourteen subjects underwent a hyperglycaemic clamp with glucagon-like peptide-1 (GLP-1) infusion and arginine injection, the morning after a 1-h walk or no exercise. Subjects were stratified by high and low fasting plasma glucose (FPG) levels and by glycated haemoglobin (HbA1c) levels, as well as by current use/non-use of antidiabetic medication. In the entire cohort, exercise did not alter insulin secretion, while glucagon levels were increased in all clamp phases (p < 0.05 to <0.01). In subjects with low FPG levels, exercise increased GLP-1-stimulated insulin secretion (p < 0.05), with the same trend being observed for arginine (p = 0.08). The same trends were seen for subjects with low HbA1c levels. Furthermore, exercise increased GLP-1- and arginine-stimulated insulin secretion (p < 0.05) in subjects who were antidiabetic drug-naïve. Exercise-induced increases in insulin secretion are blunted in subjects with T2D with high rates of hyperglycaemia and in those using antidiabetic drugs.