AI Training Zones Calculator
Generate zones across all three disciplines simultaneously, with real-time fatigue adjustment. Static calculators do one sport at a time — this does all three at once.
FAQ
Why do my zones change with fatigue?
When fatigued, your body produces the same physiological stress at lower intensities. The calculator reduces zone boundaries so you train at the right effort level even when tired.
Which HR zone model do you use?
We use the Karvonen (Heart Rate Reserve) method with 5 zones, which accounts for your resting heart rate for more personalized zones than simple percentage-of-max models.
What if I only run — do I need cycling data?
No. Select Running as your sport, enter your HR data and 5K time, and the calculator will generate HR zones and pace zones. Power zones only appear when Cycling is selected.
Methodology
Heart rate zones use the Karvonen formula (HRR = MaxHR - RestHR). Power zones follow Coggan's 7-zone model based on FTP. Pace zones derive from your 5K time as a threshold proxy. Fatigue de-rating reduces upper bounds by up to 10% at maximum fatigue.
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