Total Peripheral Resistance
The total peripheral resistance (TPR) is the resistance created by the circulatory system. This resistance needs to be overcome to push blood through the whole system.
During intense exercise, the arterioles tend to dilate. If it were not for this dilation, the blood pressure would increase dramatically. This dilation reduces the resistance to the flow of blood in the arteries, and thus, keeps the blood pressure at more normal levels.
TPR can be easily calculated by dividing the Mean Arterial Pressure (MAP) by the Cardiac Output (CO).
TPR = MAP/CO
The most common unit for TPR is