Vigorous-intensity exercise, high-intensity interval training, when that lactate production accumulates, it stimulates the expression and activity of glucose transporters known on the muscle known as GLUT-4 ... That lactate acts as a signaling molecule to increase the transport of glucose transporters on the muscle cells, and this then allows for more efficient uptake of glucose from the bloodstream into the muscle, even at rest. And so consequently, then, insulin sensitivity is also improved, and blood glucose levels are better regulated.