Health · 4 min read
Zone 2 Heart Rate: How to Find It and Why It Works
Zone 2 is easy, steady exercise: roughly 60–70% of your maximum heart rate in the common five-zone model. It should feel comfortable enough that you can talk in full sentences. It's become popular because it builds aerobic fitness very efficiently, it's easy to recover from, and you can do a lot of it. For a 45-year-old, it's roughly 106–124 bpm by percentage of max, or higher using the Karvonen method.
How to calculate your zone 2
Method 1: percentage of max heart rate
- Estimate max heart rate: 208 − 0.7 × age. For a 45-year-old: 208 − 31.5 = 176.5.
- Zone 2 = 60–70% of that: about 106–124 bpm.
Method 2: Karvonen (heart rate reserve)
- Measure resting heart rate, say 58 bpm.
- Heart rate reserve = 176.5 − 58 = 118.5.
- Zone 2 = 58 + 118.5 × 0.6 to 0.7 = about 129–141 bpm.
Those ranges are quite different, and that's normal; they're built on different assumptions. The Karvonen version often matches how zone 2 actually feels for regular exercisers. The heart rate zone calculator shows both side by side.
Check it with the talk test
Formulas get you in the right area, but your breathing is the best reality check. In zone 2 you should be able to:
- speak in full sentences without gasping,
- breathe mostly comfortably, maybe even through your nose,
- imagine keeping it up for an hour or more.
If you can only manage a few words, you're above zone 2, whatever your watch says. Some coaches also suggest the "MAF" shortcut of 180 minus your age as an upper limit for easy aerobic work, which lands close to the other methods for many people.
Why zone 2 works
- Aerobic engine: steady, easy exercise encourages adaptations in your heart and muscles that improve how well you deliver and use oxygen.
- Fat as fuel: at this intensity your body relies more on fat, and over time gets better at using it. That doesn't make it magic for fat loss; see is there really a fat-burning zone?
- Low recovery cost: you can do more total training without getting run down or injured.
- It supports harder sessions: a strong aerobic base helps you recover between intervals and races.
How much zone 2 should you do?
Health guidelines recommend at least 150 minutes a week of moderate activity for adults, and much of that can be zone 2: brisk walking, easy cycling, jogging, swimming. For endurance athletes, a large share of weekly training, often around three-quarters or more, is easy. A simple starting plan: three to four sessions of 30–60 minutes, plus one harder session if you enjoy it.
Why it feels frustratingly slow at first
Many runners find that staying in zone 2 means slowing down a lot, sometimes to a walk on hills. That's normal, especially if most of your running has been harder than you realised. Stick with it for a couple of months and your pace at the same heart rate usually improves. That's the aerobic base building.
Common mistakes
- Trusting a wrist sensor blindly. Readings can spike or lag. Use the talk test as a cross-check.
- Ignoring heat and hills. Heart rate rises in warm weather and uphill. Slow down to stay in zone.
- Making every session zone 2. A bit of harder work still helps fitness. Easy most of the time, hard sometimes.
For how zone 2 fits with the other four, see heart rate zones explained. And if you've got heart conditions or take heart-rate-lowering medication, ask your doctor which ranges are right for you.
Frequently asked questions
What is zone 2 heart rate?
Easy, conversational effort, usually defined as 60–70% of maximum heart rate, or a similar range calculated from heart rate reserve with the Karvonen method.
How do I calculate my zone 2 heart rate?
Estimate max heart rate (for example 208 − 0.7 × age) and take 60–70% of it. Or use Karvonen: resting HR + (max HR − resting HR) × 0.6 to 0.7.
How long should zone 2 workouts be?
Typically 30–60 minutes or longer. Aim for several sessions a week, alongside the general guideline of at least 150 minutes of moderate activity weekly.
Why is my zone 2 pace so slow?
Many people run most sessions harder than they realise. Staying in zone 2 often means slowing down at first, but pace at the same heart rate usually improves within a couple of months.