Questions:
1. My blood pressure for this lab was 123/78. These numbers are normal, compared to the normal rating of 120/80. My pulse pressure was 45 (SP – DP). My mean arterial pressure was 93 (DP + 1/3 (SP – DP).
2. Mean arterial blood pressure is determined by cardiac output and total vascular resistance. The mathematical equation for mean arterial blood pressure is equal to cardiac output x total vascular resistance. The amount of blood pumped out of the heart is the cardiac output, and the sum of the resistance of all systemic blood vessels is equal to the total vascular resistance. An increase of blood volume, heart rate, stroke volume, blood viscosity, and peripheral resistance can all influence an increase in blood pressure. Any of these factors would increase the forces exerted upon arterial walls, which would cause the cardiovascular control center to respond with a decrease of sympathetic activity to the heart. If there was a decrease in blood pressure, there would be a resulting reduction of baroreceptor activity to the brain, causing the cardiovascular control center to respond by increasing sympathetic outflow.
During incremental exercise, diastolic pressure remains fairly constant, and systolic pressure increases, causing an increase in mean arterial pressure. During aerobic exercise, the body is in a high demand for oxygen, therefore will increase the heart rate or dilate blood vessels in order to reduce vascular resistance and increase flow. This will lead to the increase of systolic pressure. Diastolic pressure will remain fairly constant because the dilation of the arterial walls will balance out the increase in heart