How to use the calculator

1. Enter your age.

2. Enter your resting heart rate (measure this when you're completely relaxed, preferably in the morning before getting out of bed).

3. Click "Calculate Zones" to see your personalised heart rate zones.

Guidance

This calculator uses the Karvonen Formula to determine your personalised heart rate training zones based on your age and resting heart rate (RHR).

Your maximum heart rate (MHR) is estimated using the formula 208 - (age x 0.7). This then used to calculate your heart rate reserve (HRR), which is the difference between your maximum heart rate (MHR) and your resting heart rate.

The Karvonen Formula then uses your HRR to calculate the training zones, taking into account your RHR. The zones are a percentage of the HRR plus RHR.

1. Zone 1 (Recovery): 50-60%

Light intensity, ideal for warm-up and cool-down. Improves overall health and helps in recovery.

2. Zone 2 (Aerobic): 60-70%

Low to moderate intensity, good for improving general endurance and fat burning. You can sustain this effort for long periods.

3. Zone 3 (Aerobic/Anaerobic): 70-80%

Moderate to hard intensity, improves efficiency of blood circulation in the heart and skeletal muscles. This is the upper end of aerobic exercise.

4. Zone 4 (Anaerobic): 80-90%

High-intensity exercise, increases maximum performance capacity. You're working above your anaerobic threshold.

5. Zone 5 (Maximal): 90-100%

Maximum effort that you can't sustain for more than a few minutes. Helps to increase maximum sprint speed.

Note:

1. Remember, these are only guidelines and exact zones may differ between individuals.

2. This does not constitute medical advice.