Mechanism of enhanced insulin sensitivity in athletes. Increased blood flow, muscle glucose transport protein (GLUT-4) concentration, and glycogen synthase activity.

Abstract

(a) athletes are characterized by enhanced muscle blood flow and glucose uptake. (b) The cellular mechanisms of glucose uptake are increased GLUT-4 protein content, glycogen synthase activity, and glucose storage as glycogen. (c) A close correlation between glycogen synthase fractional activity and blood flow suggests that they are causally related in promoting glucose disposal.