Training Smart, Not Just Hard
Many people believe that to get fit, every workout needs to leave you gasping for air. In reality, elite athletes spend 80% of their training time in lower intensity zones (Zone 2) and only 20% doing high-intensity work.
The Magic of Zone 2
Zone 2 is often called the "Fat Burning Zone," but its benefits go deeper. Training here improves your mitochondrial efficiency, teaching your body to use fat as fuel rather than burning through your limited sugar (glycogen) stores.
How to find it: Zone 2 is the "conversation pace." You should be able to speak in full sentences while moving, but you wouldn't want to sing a song.
Karvonen vs. The "220 - Age" Rule
Most gym machines use the simple 220 minus Age formula to find your Max Heart Rate. The problem? It assumes everyone has the same fitness level.
This calculator uses the Karvonen Formula, which factors in your Resting Heart Rate (RHR). This is far more accurate because a fit person with a low RHR has a larger "Heart Rate Reserve" to train with than an unfit person of the same age.
Frequently Asked Questions
Why is my Zone 2 pace so slow? ▼
This is the "Aerobic Deficiency Syndrome." If you have spent years doing only high-intensity cardio (HIIT), your aerobic base is likely undeveloped. Be patient. After 4-6 weeks of slow Zone 2 training, your pace will increase while your heart rate stays low.
How do I measure my Resting Heart Rate? ▼
The best time is right after you wake up, before you get out of bed or drink coffee. Count your beats for 60 seconds. Most smartwatches track this automatically overnight.