In order to calculate your training heart rate, the foremost step should be to minus your actual age from 220. For instance, if you are 20 years old, then subtracting your age from 220 would be: 220-20 = 200.
Now, you must multiply the obtained result with the 0.55 to figure out your maximum estimated heart rate. After multiplying both figures, the result will be 200*0.55= 110. This is the lowest range of your training heart rate which should be achieved during a workout.
After you have gained the lowest range of your estimated training heart rate, you must calculate your maximum range of the heart rate during training. Note that this is the heart rate which should not be crossed during your work out. For this, you must multiply the result obtained in step 1 by the 0.90. For example, after multiplying 200 by 0.90 the result will be 180. For a healthy person, this rate should never be overachieved.
Now you must analyse the results obtained in step 2 and 3. For instance, the range of training heart rate for a 20-year-old person is 110 to 180 per minute.
In order to monitor your training heart rate, you must place your middle and index finger on your neck. You can also use thumb for this purpose, but is has a considerably low pulse and there is a strong chance, that you might not be able to count properly you must place your fingers on the neck for at least 15 seconds and count each pulse.
Now multiply the obtained result by four and you will have your total number of beats per minute. After you have obtained the result, you must compare it with the lowest and maximum range to ensure whether it falls between the range or not.