Selecting the correct intensity level is vital to the success of your cardio training.  There are three commonly used methods to determine your target heart zone for fat burning: the Karvonnen Method, the Age Predicted Method, and the Borg Perceived Exertion Scale.

The Karvonnen Method is the most effective of the three but it requires that you know your resting heart rate; this should be taken before you get out of bed in the morning. This is determined by counting your pulse, either at the wrist or the side of your neck for a full 60 seconds.  A true resting heart rate should be taken in the morning as soon as you wake up and before getting out of bed or consuming any stimulants such as coffee or tea.

Your resting heart rate is a very good indicator of your cardiovascular fitness level.  The better your cardiovascular fitness, the lower your resting heart rate will be.  Some endurance athletes, who compete in the Iron man or run marathons, have resting heart rates as low as 40 beats per minute.

The Karvonnen Method:
1.    Determine your predicted maximal heart rate: 220- your age
2.    Determine your heart rate reserve.  This is your predicted maximal heart rate minus your resting heart rate.
3.    Multiply the results of step 2 by your desired intensity level; 60%, 70%, etc.
4.    Determine your target heart rate range by adding back into the formula your resting heart rate.

Let’s use Joe Exercise as our example.  Joe is 50 years old and has a resting heart rate of 75.  Since Joe has such a high resting heart rate we can assume he is in poor cardiovascular shape and we will have him start at 50% intensity.

1.    220 - 50 = 170 (Predicted Maximal Heart Rate)
2.    170 - 75 = 95 (Heart Rate Reserve)
3.    95 X 50% = 48 (low intensity level)
4.    48 (beats per minute) + 75 (resting heart rate) = 123

Joe’s target heart rate is 123 beats per minute