Short-term aerobic exercise improves arterial stiffness in type 2 diabetes

Objective: To investigate whether: (1) aerobic exercise decreases arterial stiffness and (2) reduction in arterial stiffness is associated with improvement in insulin resistance in type 2 diabetes. Methods: Common carotid and femoral arterial stiffness was ultrasonographically evaluated using stiffness index beta in 23 type 2 diabetic subjects before and after a 3-week exercise protocol including ergometer and walking. Insulin sensitivity (Clamp-IR) was assessed using euglycemic-hyperinsulinemic clamp before and after the protocol. Arterial stiffness was also examined in steady hyperinsulinemic state during clamp. Results: Anthropometrical factors did not change following exercise. Clamp-IR tended to increase after exercise protocol (P = 0.061). Stiffness index beta decreased following exercise in both common carotid and femoral arteries (P = 0.020 and P < 0.001, respectively). DeltaClamp-IR was significantly correlated with the changes in stiffness index beta of both common carotid (P = 0.040) and femoral artery (P = 0.016). Divided into tertiles according to DeltaClamp-IR, decreases in stiffness index 0 for both common carotid (P = 0.009) and femoral (P = 0.037) arteries was greater in tertile group with a higher DeltaClamp-IR. Hyperinsulinemia during clamp decreased stiffness index in both common carotid (P = 0.031) and femoral (P = 0.025) arteries before exercise, but these effects disappeared after the exercise protocol. Conclusions: Short-term aerobic exercise significantly decreased arterial stiffness in both common carotid and femoral arteries, and the reduction of stiffness was associated with improvement of insulin resistance in type 2 diabetes. (C) 2003 Elsevier Ireland Ltd. All rights reserved.