Karvonen-based 5-zone training ranges from age and resting HR (Tanaka + ACSM 2022).
Heart-rate zones are an informational reference, not a prescription or diagnosis. Rate-controlling medications (beta-blockers, calcium-channel blockers, some antiarrhythmics) alter both maximum and reserve heart rate — please plan targets with a qualified healthcare professional if you take any of these or have known heart disease. Stop exercising and seek urgent medical attention for chest pain, fainting, severe breathlessness or unusual palpitations.
In your 30s and 40s, aerobic base training (Zone 2) is the single most productive investment. Interval work still improves VO₂max — start conservatively and progress.
HR reserve = HRmax − HRrest = 119 bpm. HRmax estimated by Tanaka 2001 (208 − 0.7 × age). Zones based on ACSM 2022.
| Category | Range |
|---|---|
| Zone 1 — Very light | 50 – 60 % HRR |
| Zone 2 — Light | 60 – 70 % HRR |
| Zone 3 — Moderate | 70 – 80 % HRR |
| Zone 4 — Vigorous | 80 – 90 % HRR |
| Zone 5 — Maximum | 90 – 100 % HRR |
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This tool estimates a maximum heart rate (Tanaka 2001: HRmax = 208 − 0.7 × age) and derives five training zones from your heart-rate reserve (Karvonen 1957) using the ACSM 2022 five-zone model. Individual maximum heart rate typically varies by around ±10–12 bpm around any age-based formula, and the zones are best interpreted as informational reference ranges rather than exact prescriptions.
Use the zones as a starting reference alongside perceived effort and how you feel — not as a fixed target. If you take rate-controlling medications or have any diagnosed heart condition, please plan targets with a qualified healthcare professional before using these ranges. Stop exercising and seek urgent medical attention for chest pain, fainting or near-fainting, severe breathlessness that is out of proportion to effort, or unusual palpitations.
These zones are an informational estimate, not a diagnosis or a medical prescription. They do not replace clinical assessment, and they should not be used unadjusted by people on rate-controlling medication or with known heart disease.
In your 30s and 40s, aerobic base training (Zone 2) is the single most productive investment. Interval work still improves VO₂max — start conservatively and progress.
Consider a clinician visit for cardiovascular risk assessment if you are starting vigorous training after a sedentary period. This is routine, not alarming.