What are the 5 heart rate training zones?

Zone 1 (50–60% HRmax): Recovery. Zone 2 (60–70%): Base aerobic, fat burning. Zone 3 (70–80%): Aerobic threshold, "comfortably hard." Zone 4 (80–90%): Lactate threshold, race pace. Zone 5 (90–100%): Maximal VO2max efforts, intervals. Zones 2 and 4 have the highest training value per unit of stress.

How do I find my maximum heart rate accurately?

The 220-minus-age formula has a standard deviation of ±10–12 bpm — meaning it can be wrong by 20+ bpm. More accurate methods: the Tanaka formula (208 − 0.7 × age) for older adults, or a maximal effort field test (1-mile all-out run or 3-minute ramp test). Wearable heart rate monitors during max effort are practical.

What percentage of training should be in Zone 2?

Elite endurance athletes train 75–80% of their volume in Zone 1–2 (low intensity) and 10–15% in Zones 4–5 (high intensity). This "polarized" or "80/20" model is supported by research on elite runners, cyclists, and rowers. Most amateur athletes train too much in Zone 3 — the "gray zone."

Does heart rate training improve marathon performance?

Yes. Zone 2 training builds mitochondrial density, improves fat oxidation, and increases stroke volume. Athletes who consistently train below lactate threshold for 6–12 weeks show 5–10% VO2max improvements without additional fatigue. It's the foundation of all successful endurance training programs (Lydiard, Maffetone).

Heart Rate Zone Calculator

Calculate your 5 training zones based on Max Heart Rate or Heart Rate Reserve (Karvonen).

Heart RateZonesTrainingCardio

Section: Athletic Performance
Reviewed: 2026-02-12
Your data: Stays local

Zone Method

Uses Heart Rate Reserve. More personalised — accounts for your resting heart rate.

Age

Max Heart Rate

Tanaka formula: 208 − (0.7 × age) = 187 BPM(more accurate than 220−age)

Resting Heart Rate (RHR) (RHR)

Measurement taken when calm and still (e.g., waking up).

RHR 60HRmax 187

Low intensityHigh intensity

Heart Rate Zones — Karvonen (HRR)

Zone 1

124–136

BPM

Zone 1 — Recovery

Active recovery. Very easy effort. Fat metabolism dominant.

50–60% HRR

Zone 2

136–149

BPM

Zone 2 — Aerobic Base

Conversational pace. Builds aerobic base and mitochondrial density.

60–70% HRR

Zone 3

149–162

BPM

Zone 3 — Tempo

Comfortably hard. Marathon race pace for most athletes.

70–80% HRR

Zone 4

162–174

BPM

Zone 4 — Threshold

Hard effort. Improves lactate clearance and speed endurance.

80–90% HRR

Zone 5

174–187

BPM

Zone 5 — VO₂max

Maximum effort. Short intervals only. Develops peak aerobic power.

90–100% HRR

Why results differ between methods: Each method calculates zones differently. Karvonen personalises for your resting HR. HRmax% is what Garmin/Polar use. MAF targets aerobic base building. Polarized reflects research-backed 80/20 training distribution.

For most athletes: use Karvonen or HRmax% for general training. Polarized if following a structured endurance plan.

Method and basis

How the figure above is derived, and when not to act on it.

Understanding the 5 Zones

Heart Rate training is about targeting specific physiological adaptations. 1. Zone 1 (Recovery): < 60%. Promotes blood flow and active recovery. 2. Zone 2 (Endurance Base): 60 - 70%. The "Fat Burning" zone. Builds mitochondrial density and capillary networks. You should be able to speak in full sentences. 3. Zone 3 (Tempo / Grey Zone): 70 - 80%. Often called "junk miles" because it's too hard for recovery but too easy for threshold gains. 4. Zone 4 (Threshold): 80 - 90%. Improves your ability to clear lactate. "Comfortably hard." 5. Zone 5 (VO2 Max): 90 - 100%. Peak aerobic capacity. Can only be held for a few minutes.

Heart Rate Training Zones

Zone	Intensity (%)	Feeling	Benefit
Zone 1	50 - 60%	Very Easy	Recovery, Warm-up
Zone 2**	60 - 70%	Conversational	**Base Building, Fat Burn
Zone 3	70 - 80%	Moderate	Aerobic Capacity (Grey Zone)
Zone 4	80 - 90%	Hard	Lactate Threshold
Zone 5	90 - 100%	Maximum	VO2 Max, Anaerobic Speed

Max HR vs. Heart Rate Reserve (Karvonen)

* Simple Max HR: 220 - Age. Often inaccurate. * Karvonen Formula**: Uses your **Resting Heart Rate (RHR) to determine your "reserve." * *Formula*: (MaxHR - RHR) * % Intensity + RHR * *Verdict*: Much more accurate for trained individuals.

The 80/20 Rule

Elite endurance athletes spend 80% of their time in Zone 2** and only **20% in Zone 4/5. Spending too much time in Zone 3 leads to stagnation and burnout.

WinSport Editorial & Research Standards

All formulas and reference values used in this tool are sourced from peer-reviewed scientific literature and validated clinical guidelines. Our research team continuously audits each calculator for accuracy and updates methodology as new evidence emerges.

How these pages are written and reviewed

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