Why use the Karvonen Formula?
Simple heart rate calculations (`220 - Age`) assume everyone has the same fitness level. The Karvonen formula incorporates your Resting Heart Rate (RHR).
As you get fitter, your RHR drops, and your Heart Rate Reserve (HRR) increases, giving you a wider accurate training range tailored to your specific physiology.
Zones Breakdown
- Zone 2 (60-70%): The "all day" pace. Builds mitochondrial efficiency and burns fat.
- Zone 4 (80-90%): Threshold training. Improves your ability to sustain high intensity.
- Zone 5 (90%+): VO2 Max territory. Improves peak power.
