Which of the following occur after 1 minute of standing, compared to the recumbent position?
Standing up increases the transmural pressure in the veins of the legs. Because the veins are highly compliant, their volume increases at the expense of central blood volume.A lower central blood volume means reduced cardiac filling pressure (preload). Within seconds, the decrease in preload decreases stroke volume, cardiac output, and aerial pressure.Ref: Guyton; 13th edition
Skin blood flow increases
Volume of blood in leg veins increases
Cardiac preload increases
Cardiac contractility decreases
General physiology