Calculate the training zone as a percentage of max heart rate. Determine your max HR by subtracting your age from 220, and then multiply by the target range. For example, the max HR for a 30 year old would be 190 (220 - 30). And 70 to 80 percent of the max HR would be 133 to 152 beats per minute (BPM).

Since all people of a particular age do not have the same max HR, it is important to remember that the 220 minus age formula is only an estimate and can be off by as much as 10-15 BPM. A more accurate approach would be to test your max HR once you have developed the necessary conditioning.

Calculate the training zone as a percentage of heart rate reserve (HRR).

This method is more accurate because it considers both the max HR and resting HR (RHR).

HRR is the difference between max HR and RHR. To calculate, subtract your RHR from your max HR. Then multiply by the desired percentage and add the RHR to the product.

This example shows a thirty year old with a max HR of 190 and a RHR of 50 BPM. HRR = (190 - 50) or 140 BPM.

The lower limit is (140 x 0.70) + 50 = 148. Upper limit is (140 x 0.80) + 50 = 162. So the target range is 148 to 162 BPM.

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How do you monitor heart rate?

You can monitor your heart rate by checking your pulse or you can use a heart rate monitor. To check your pulse, use a second hand on a wristwatch or clock. Count the beats for 15 seconds and multiply by four. I prefer a heart rate monitor because it offers valuable feedback throughout the entire workout.