This prevents blood flow to the extremities. The shunts open and blood is directed to deep tissues. As mentioned earlier there will be an increase in heat production. Factors controlling heat production by increasing cellular metabolism includes muscle activity such as exercise and shivering, thyroxine, epinephrine and norepinephrine, chemical thermogenesis. In conclusion, body temperature is controlled by balancing heat production against heat loss.
Temperature regulation is determined by hypothalamus signals and local receptor reflexes.
Heat loss mechanisms includes vasodilation, sweating and decreased metabolism. Heat production includes vasoconstriction, shivering and increased metabolism. Lipid Metabolism, 865-875. Textbook of Medical Physiology. W.B. Saunders Company.