Finding the body’s target heart rate (THR) is essential for those interested in maximizing the effectiveness of their workouts and training programs and reducing the risk of overexertion.
There is an easy method for determining your THR: Subtract your age from 220 (226 for women); this will provide your estimated maximum heart rate (MHR). Multiply your MHR by the percentages listed for the appropriate exercise zone from the list below.
- Healthy Heart – For low-intensity exercises and warm ups. The THR for this zone is 50%-60% of the MHR.
- Fitness – For more intense but generally low to moderate effort exercises. The THR for this zone is 60%-70% of the MHR.
- Aerobic – This zone helps build endurance and increases the strength and size of your heart. It also improves your cardiovascular and respiratory system. The THR for this zone is 70%-80% of the MHR.
- Anaerobic – For performance training. This zone increases the amount of oxygen you can consume during physical exertion. The THR for this zone is 80%-90% of the MHR.
- Red Line – For maximum intensity exercises that burn the most calories. The THR for this zone is 90%-100% of the MHR. This level should only be attempted by those in excellent shape who have been cleared by a physician or qualified medical examiner.
So, for example, a 40-year-old woman who wishes to find her THR for a fitness zone program would use the following equation: (226 – 40) X 60% = 111 (low end) and (226 – 40) X 70% = 130 (high end). Therefore, as long as she maintains her heart rate between 111 beats per minute (bpm) and 130 bpm, the woman is at the proper target heart rate for maximum exercise efficiency and safety.
A more accurate method for determining your THR is the Karvonen formula, but this requires that you determine your resting heart rate (RHR) and your heart rate reserve (HRR). Measure your resting pulse (your heart rate just as you wake up) three mornings in a row. Your RHR is the average of these three readings (add the readings and divide by three). Your HRR is your MHR minus your RHR. Once you have calculated your HRR, multiply it by the percentages for the zone you want to target for and add the RHR. The equations are as follows:
MHR = 220 (or 226 for women) – age (in years)
RHR = average resting heart rate (average of 3 readings)
HRR = MHR – RHR
THR = (HRR * target zone percentage) + RHR
So for our hypothetical 40-year-old woman targeting a fitness zone…
MHR = 226 – 40 = 186.
RHR = (64 + 62 + 63)/3 = 63
HRR = 186 – 63 = 123
THR = (123 * 60%) + 63 = 137 (for the low end) and (123 * 70%) + 63 = 149 (for the high end)
If you have any doubts or questions about the proper method for determining your THR, ask your chiropractor, physical therapist or doctor for help.