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Although skeletal muscle comprises about 40% of body weight, it receives only about 15% of cardiac output. In short, blood flow to skeletal muscle, when the human is at rest, is "miserly," according to Kenneth L. Zierler, MD, associate professor of medicine at the Johns Hopkins University and Hospital, who addressed the Hahnemann Symposium on Shock and Hypotension, Mar 18-21 in Philadelphia.
This miserly flow is necessary Zierler said, because if all vascular beds in the skeletal muscle were to dilate simultaneously, they could carry blood at the rate of 15 liters per minute, or about three times normal cardiac output in the basal state. It is, in fact, the near maximal constriction of these vessels in the basal state that permits the human to survive with a relatively small cardiac output; otherwise, Zierler said, "we would die in shock or require a resting cardiac output of 20 liters per
Circulation, Pharmacology, and Shock. JAMA. 1964;187(13):31-32. doi:10.1001/jama.1964.03060260079043