Training With Heart Rate Zones

Zone 2 — The Most Important Zone

Zone 2 (60–70% max HR) is the foundation of endurance fitness. Training here for 80% of your sessions builds mitochondrial density, improves fat oxidation, and builds aerobic base without excessive recovery time.

The Karvonen Formula

This calculator uses the Karvonen method, which accounts for resting heart rate: Target HR = Resting HR + (Max HR − Resting HR) × Zone %. This gives more personalised zones than using max HR alone.

How to Find Your Resting Heart Rate

Measure first thing in the morning before getting out of bed. Count beats for 60 seconds. Do this 3 days in a row and take the average for the most accurate reading.

Heart Rate Zones Calculator

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