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BMI Calculator Prepare for Medical

Heart Rate Zone Calculator

Estimate your maximum heart rate and training zones to pace workouts on board.

Heart Rate Zone Calculator

Formula-based maximum heart rate can differ from your true maximum by 10 bpm or more. Some medicines (e.g. beta-blockers) change heart-rate response.

SeafarerFit provides educational information, health calculators, screening tools and medical-examination preparation resources. It does not provide diagnosis, treatment, medical certification or official determination of fitness for sea service.

Your answers are calculated in your browser and are not sent to SeafarerFit.

Using heart-rate zones at sea

Zones help you train at the right effort: easy sessions in zones 1–2 build endurance and recovery, while short intervals in zones 3–4 improve fitness quickly — useful when gym time is limited between watches.

If you add your resting heart rate (measured on waking, before getting up), the calculator uses the heart-rate-reserve (Karvonen) method, which accounts for your current fitness.

Stop exercising and seek medical help if you experience chest pain, severe breathlessness, dizziness or palpitations.

Sources

  1. Tanaka H, Monahan KD, Seals DR — Age-predicted maximal heart rate revisited (J Am Coll Cardiol, 2001) (opens in a new tab) (January 1, 2001)

Links go to the original publishers. SeafarerFit is not affiliated with or endorsed by these organizations.

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