How to Calculate Your Workout Heart Rate Using the Karvonen Formula

The Karvonen Formula is a well used, well documented mathematical formula that helps you determine your cardiovascular training intensity. The formula is based on you age predicted maximum heart rate, which is your maximum heart rate (MHR) minus your age. Training at various percentages of your age-predicted maximum heart rate will help you achieve different workout results. Follow these steps to learn how to use the Karvonen Formula:

Difficulty: Moderately Easy

Instructions

1. Figure your age-predicted maximum heart rate. Now for many years this has been done by taking 220 minus your age. However, the older formula has been updated and documented in the Medicine & Science in Sports & Exercise. The new formula is thought to be more accurate and calculates the age-predicted maximum heart rate in the following manner: 206.9 - (0.67 x age).

2. Now take your age-predicted maximum heart rate from step one and subtract your resting heart rate. Note: The best time to determine your resting heart rate is immediately after awaking in the morning without the use of an alarm clock. The average resting heart rate is considered to be around 70 beats per minute.

3. Multiply your number from step two by the percetage low-end and the percentage high-end of the zone and results you want to achieve. The common breakdown of these training zones is as follows: 50% - 60% = low intensity for efficiency and recovery, 60% - 70% = optimal fat-burning zone, 70% - 80% = aerobic zone, 80% - 90% = anaerobic zone, or 90% - 100% = maximal zone. See the tips section for more on each zone.

4. Add back your resting heart rate to both the low-end and the high-end of the zone in which you want to train. The two numbers you are left with are the lower and upper heart rates in beats per minute for the training zone you have chosen.

Tips & Warnings

• Use a heart rate monitor to accurately track your workout intensity
• 50-60% Best when used to recover from soreness, injury, or illness. Ideal during the use of reduced-calorie diets or when you desire to burn calories with minimal impact on muscle gains. Downside: longer time to burn calories.
• 60-70% Best when your main goal is to burn the highest percentage of fat.
• 70-80% Best when your main goal is to burn a high amount of calories and a lower percentage of fat. This zone builds your heart and lungs ability to supply your muscles with the necessary oxygen required to sustain higher intensity cardiovascular training.
• 80-90% Best when used as interval training, so this zone is used in short bouts to improve your heart and lungs ability to react and respond to more intense cardiovascular demands. The body takes longer to recover from this zone and anything higher so your metabolism increases.
• 90-100% Should only be used when training for an athletic event and with the guidance and supervision of a health professional. This zone is used during medical evaluations and requires medical professionals trained in advanced life support.
• Always consult your physician before engaging in cardiovascular or resistance training.