Explain how to calculate your target heart rate zone. understand the importance of knowing your target heart rate zone.

The age-related number of beats per minute of the heart when working at its maximum that is usually estimated as 220 minus one's age reached 90 percent of his maximum heart rate when tested on a treadmill.

 Since understanding your heart rate is critical to exercising safely, effectively and enjoyably.

Use the tips of your first two fingers (not your thumb) to press lightly over the blood vessels on your wrist. Count your pulse for 10 seconds and multiply by 6 to find your beats per minute. You want to stay between 50 percent to 85 percent of your maximum heart rate. This range is your target heart rate.