What heart rate should I run at for Zone 2?

Zone 2 heart rate is typically 60 to 70 percent of your maximum heart rate, though definitions vary slightly by the system you use. For a runner with a max HR of 185, that puts Zone 2 roughly between 111 and 130 beats per minute. A reliable field test: you should be able to speak in full sentences without gasping. If you can sing, you are too easy; if you cannot finish a sentence, you have drifted into Zone 3. Many athletes with aerobic bases find their Zone 2 feels deceptively slow at first, which is normal. Consistency at this intensity over months builds the aerobic engine that underlies every race.