Psychology 2036A/B Lecture Notes - Lecture 22: Hematocrit, Partial Pressure, Exercise Intensity

• School: Western University
• Department: Psychology
• Course: Psychology 2036A/B
• Professor: Doug Hazelwood

Document Summary

Both systolic and diastolic bp much higher during arm work. Key difference (mechanisms behind difference between bp): differences in radius of vasculature in arms compared to blood vessels in legs (less resistance in legs compared to arms) The greater the radius, the greater the pressure required to maintain same flow. Increase the stimulus to increase red blood cell growth from the bone marrow --> makes blood more viscous. When blood is more viscous its thicker, which means you need to work harder to pump it. Cardiovascular drift= increase in hr over time with no change in cardiac output. Red line (square) cardiac output doesn"t change but there is change in hr (goes up 15%) With systolic pressure every beat stretches and compresses the walls, over time is starts to vasodilate and radius starts to increase --> pressure is going to drop. If pressures in arterial side drops, you need to increase hr to maintain flow.