The Target Heart Rate Zone is calculated using a formula that takes into account your age, resting heart rate, and the desired exercise intensity level.

Maximum Heart Rate (Max HR): The maximum heart rate is 220 minus your age. This provides a general estimation of the maximum heart rate, which is the highest heart rate one can achieve during intense exercise.

Max HR = 220 − Age

Resting Heart Rate (RHR): This is the number of heartbeats per minute while the body is at complete rest, typically measured when a person is in a fully relaxed state.

Target Heart Rate Zone: The target heart rate zone is then calculated based on the selected exercise intensity. The Karvonen Formula is often used for this purpose.

Target HR = RHR + (Intensity × (Max HR − RHR))