GH
Zone 2 Heart Rate
Calculator
The Karvonen Method for precision training.
Measure in bed upon waking.
ANALYZING CARDIAC DATA...
⚠️ Medical Disclaimer:
This calculator uses the Karvonen formula for educational purposes. It assumes a healthy cardiovascular system. If you have heart conditions or take beta-blockers, these numbers may not apply. Consult a cardiologist before starting high-intensity training.
This calculator uses the Karvonen formula for educational purposes. It assumes a healthy cardiovascular system. If you have heart conditions or take beta-blockers, these numbers may not apply. Consult a cardiologist before starting high-intensity training.
❤️ Why "Zone 2" is the Holy Grail of Biohacking
Zone 2 training is defined as the highest metabolic output you can sustain while keeping lactate levels below 2 mmol/L. In this zone, your body prioritizes fat oxidation and builds mitochondria, the power plants of your cells.
Dr. Peter Attia and other longevity experts cite Zone 2 cardio as the single most potent tool for improving metabolic flexibility and insulin sensitivity. Unlike HIIT (Zone 5), Zone 2 can be performed 3-4 times a week without excessive central nervous system fatigue.
Understanding Your 5 Zones
- Zone 1 (Recovery): Very light effort. Improves blood flow and aids recovery.
- Zone 2 (Endurance): The "Biohacker Zone". You should be able to hold a conversation, but it feels slightly strained.
- Zone 3 (Aerobic): The "Grey Zone". Too hard for recovery, too easy for max performance benefits. Often avoided in polarized training.
- Zone 4 (Threshold): Hard effort. Sustainable for 10-60 minutes. Improves lactate clearing.
- Zone 5 (VO2 Max): Maximum effort. Sustainable for only a few minutes. Increases your aerobic ceiling.
Frequently Asked Questions (FAQ)
Why is Karvonen better than 220-Age? +
The standard "220 minus age" formula ignores your fitness level. The Karvonen formula uses your Resting Heart Rate (RHR) to tailor the zones to your actual cardiovascular health. A lower RHR indicates better fitness and shifts your zones.
How much Zone 2 should I do? +
Most longevity protocols suggest 150 to 180 minutes of Zone 2 cardio per week, split into 3-4 sessions of 45-60 minutes.
How do I know if I am in Zone 2 without a monitor? +
Use the "Talk Test". You should be able to speak a full sentence comfortably, but you shouldn't be able to sing a song.