Cardiovascular efficiency is a measure of how effectively the circulatory system delivers oxygen to the rest of the body through the bloodstream. It can be measured in different ways, including counting beats per minute and calculating the maximum volume of oxygen that can be consumed during an individual's exercise.
Counting beats per minute is a simple and effective way to measure cardiovascular efficiency. The goal is to compare an individual's BPM at rest (low activity) to his or her BPM during exercise (high activity). This will show how much harder the heart is working under stress and can be expressed as the ratio of low-activity BPM to high-activity BPM. This can be compared to a standard ratio or an individual’s past results during similar exercises. The BPM method is an effective way to track a person’s improvement in cardiovascular efficiency over time.
A more precise method of measuring cardiovascular efficiency involves measuring the maximum volume of oxygen the body is consuming at an individual's maximum heart rate. The subject first has to reach his or her maximum heart rate, and this is accomplished by extended treadmill exercise until the person’s BPM is no longer increasing. At this point, he or she is consuming the maximum volume of oxygen possible, and his or her heart is delivering it to the body at the fastest rate it can. At the same BPM, a person with higher cardiovascular efficiency will deliver more oxygen than a person with lower cardiovascular efficiency. This also means that the person with higher cardiovascular efficiency can deliver the same amount of oxygen through the bloodstream at a lower BPM than the person with lower cardiovascular efficiency.