What Are Heart Rate Training Zones?
Heart rate training zones divide your heart rate range — from resting to maximum — into five intensity bands. Training in the right zone for your goal is one of the most effective ways to improve fitness: Zone 2 builds aerobic base and burns fat; Zone 4 raises your lactate threshold; Zone 5 develops speed and power.
The Karvonen Formula
This calculator uses the Karvonen formula, which accounts for your resting heart rate and is more personalised than the simpler percentage-of-max-HR approach:
Target HR = ((Max HR − Resting HR) × Intensity%) + Resting HR
Max HR = 220 − Age
Max HR = 220 − Age
How to Use Your Zones
Most training programmes recommend spending 80% of training time in Zones 1–2 (low intensity) and only 20% in Zones 4–5. This “polarised” approach builds a strong aerobic base while allowing adequate recovery between high-intensity sessions.
Frequently Asked Questions
How do I find my resting heart rate?
Measure it first thing in the morning before getting out of bed. Count your pulse for 60 seconds, or for 30 seconds and double it. Do this for 3–5 days and average the results.
Is the 220 minus age formula accurate?
It is a population average with high individual variation (±10–20 bpm). A more accurate max HR can be determined through a maximal exercise test, but the formula is a safe and practical estimate.
What zone is best for fat loss?
Zone 2 (60–70% max HR) burns the highest proportion of calories from fat, but total calorie burn ultimately determines fat loss. Higher-intensity zones burn more total calories in less time.
Medical Disclaimer: This calculator is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for health decisions.