So you started your exercise program. How do you know if what you are doing is sufficient enough to bring about cardiovascular improvements? One way that you can gauge your effort is by examining your intensity level.
Intensity is how much effort you put into your exercise. According to the American College of Sports Medicine (ACSM) your intensity level should be between 60% and 90% of your maximum heart rate. This level of intensity is often referred to as your target heart rate (THR) zone. In order to find this level here are few simple calculations:
Predicted Maximal Heart rate (PMHR) = 220 - age
60% = PMHR X .60
90% = PMHR X .90
For instance, a 45 year female's THR zone would be
PMHR: 220 - 45 = 175
60%: 175 x .60 = 105
90%: 175 x .90 = 158
Therefore this individual should be exercising at a level that elevates her heart rate between 105 and 158.