Find your personalised heart rate training zones based on your age and resting heart rate. Know exactly which zone you're in during exercise and what each one achieves.
Heart rate training zones divide the range from rest to maximum heart rate into bands, each associated with a different physiological response and training effect. Training in the right zone for the right purpose is one of the most evidence-backed principles in exercise science.
| Zone | % Max HR | Feel | Primary Benefit |
|---|---|---|---|
| Zone 1 — Recovery | 50–60% | Very easy — can hold full conversation | Active recovery, base aerobic conditioning |
| Zone 2 — Fat burn / Aerobic base | 60–70% | Easy — can talk in sentences | Fat oxidation, mitochondrial density, aerobic base |
| Zone 3 — Aerobic | 70–80% | Moderate — sentences becoming harder | Cardiovascular efficiency, lactate threshold |
| Zone 4 — Threshold | 80–90% | Hard — can only say short phrases | Lactate threshold, race pace, VO2 max stimulus |
| Zone 5 — Maximum | 90–100% | All-out — cannot speak | VO2 max, neuromuscular power, peak performance |
Zone 2 training has attracted significant scientific interest as the foundation of cardiovascular longevity. At this intensity, the body primarily uses fat as fuel through the aerobic mitochondrial pathway — stimulating mitochondrial biogenesis (the creation of new mitochondria) and improving metabolic flexibility.
Elite endurance athletes typically spend 75–80% of their training in Zone 2. Research by Dr. Iñigo San Millán shows that Zone 2 capacity is one of the strongest predictors of metabolic health — directly linked to insulin sensitivity, fat oxidation efficiency, and cardiovascular risk.
Maximum heart rate declines reliably with age — roughly 1 bpm per year. The classic formula (220 minus age) is a population average with significant individual variation (±10–12 bpm). The Tanaka formula (208 − 0.7 × age) is considered more accurate for older adults.
If you take beta-blockers (prescribed for blood pressure or heart conditions), they significantly lower your maximum and resting heart rate, making standard zone calculations unreliable. Use perceived exertion (the "talk test") instead of heart rate zones if you're on beta-blockers.
The Karvonen (heart rate reserve) method incorporates your resting heart rate for more individualised zones. Heart Rate Reserve = Max HR − Resting HR. Zones are then calculated as: Resting HR + (HRR × zone percentage). This accounts for your current fitness level — a fitter person with a lower resting HR will have different zones than an unfit person with the same max HR.