INS and hyperinsulinism: The metabolic studies were initiated with a pancreatic clamp (the use of somatostatin to inhibit endogenous insulin and glucagon secretion), accompanied by IV-delivered hyperinsulinemia (65 ± 12 and 82 ± 11 pmol/L in trained and untrained, respectively; p = NS), and the plasma glucose level was maintained at euglycemia by an IV infusion of dextrose (4.9 mmol/L in both groups).