Heart rate training takes the guesswork out of running. By monitoring your heart rate, you can ensure you're training at the right intensity for your goals—whether that's building endurance, improving speed, or recovering properly.
Finding your maximum heart rate
The classic formula of 220 minus your age provides a rough estimate, but individual variation can be significant. A more accurate method is a field test: after warming up, run hard up a steep hill for 2-3 minutes, jog down, then repeat. The highest heart rate you hit is close to your max.
The five heart rate zones
Training zones are expressed as percentages of your maximum heart rate:
- Zone 1 (50-60%): Very easy, recovery pace
- Zone 2 (60-70%): Easy, conversational running
- Zone 3 (70-80%): Moderate, tempo effort
- Zone 4 (80-90%): Hard, threshold running
- Zone 5 (90-100%): Maximum effort, sprinting
The 80/20 rule
Research shows that elite runners spend about 80% of their training in Zones 1-2 and only 20% in Zones 3-5. Most recreational runners do the opposite—running too hard on easy days and too easy on hard days. Following the 80/20 principle leads to better results with less injury risk.
Zone 2: Your secret weapon
Zone 2 training builds your aerobic base—the foundation of all running performance. It improves fat burning, increases mitochondria in your muscles, and builds endurance. It should feel easy, almost too easy. If you can't hold a conversation, you're going too fast.
Why zone 2 feels slow
Many runners resist Zone 2 because it feels embarrassingly slow. But this easy running is where the magic happens. Your heart gets stronger, your capillary network expands, and you build the endurance that makes faster running possible.
Using heart rate in workouts
Different workouts target different zones:
- Easy runs: Stay in Zone 2
- Long runs: Mostly Zone 2, maybe touching Zone 3
- Tempo runs: Zone 3, approaching Zone 4
- Intervals: Zone 4-5 during hard efforts, Zone 1-2 during recovery
Heart rate vs. pace
Heart rate is more reliable than pace in many situations. Hills, heat, humidity, fatigue, and stress all affect how hard a given pace feels. Heart rate accounts for these factors. If your heart rate is too high for an easy run, slow down—even if your pace seems slow.
Common heart rate training mistakes
- Ignoring cardiac drift: Heart rate naturally rises during long runs even at steady effort
- Not accounting for conditions: Heat can raise heart rate by 10+ beats per minute
- Obsessing over the numbers: Use heart rate as a guide, not a prison
Heart rate training is a powerful tool when used correctly. Start by spending more time in Zone 2, save the hard efforts for designated workout days, and watch your fitness improve.