What is Zone 2?
Zone 2 is the second of five heart rate training zones: easy, conversational aerobic exercise. In the most common model it is 60–70 % of your maximum heart rate. Physiologically, it corresponds to the highest intensity you can hold while your muscles are still clearing lactate as fast as they produce it — often described as around the first lactate threshold.
Zone 2 has become one of the most talked-about ideas in endurance training and in health and longevity circles, thanks to coaches and researchers such as Iñigo San Millán, who works with elite cyclists, and to the long-standing observation that the best endurance athletes do most of their training at low intensity.
How Zone 2 is calculated
Karvonen: Zone 2 = resting HR + 0.60 × (max HR − resting HR) to resting HR + 0.70 × (max HR − resting HR)
Max HR estimate: 208 − 0.7 × age (Tanaka) or 206 − 0.88 × age for women (Gulati)
If you do not know your maximum heart rate, the calculator estimates it from age. Because individual max heart rates vary by 10–15 beats either side of any formula, a measured max HR — or at least your resting HR for the Karvonen method — gives a more trustworthy range.
Zone 2 heart rate chart by age
Zone 2 ranges using the Tanaka formula (men) and Gulati formula (women), plus a Karvonen range assuming a resting heart rate of 60 bpm. Click any age for a full page with all five zones.
| Age | Men (Tanaka) | Women (Gulati) | 220 − age | Karvonen (RHR 60, men) |
|---|---|---|---|---|
| 20 | 116–136 bpm | 113–132 bpm | 120–140 bpm | 140–154 bpm |
| 25 | 114–133 bpm | 110–129 bpm | 117–136 bpm | 138–151 bpm |
| 30 | 112–131 bpm | 108–126 bpm | 114–133 bpm | 136–149 bpm |
| 35 | 110–128 bpm | 105–123 bpm | 111–130 bpm | 134–146 bpm |
| 40 | 108–126 bpm | 102–120 bpm | 108–126 bpm | 132–144 bpm |
| 45 | 106–124 bpm | 100–116 bpm | 105–122 bpm | 130–142 bpm |
| 50 | 104–121 bpm | 97–113 bpm | 102–119 bpm | 128–139 bpm |
| 55 | 102–119 bpm | 95–110 bpm | 99–115 bpm | 126–137 bpm |
| 60 | 100–116 bpm | 92–107 bpm | 96–112 bpm | 124–134 bpm |
| 65 | 98–114 bpm | 89–104 bpm | 93–108 bpm | 122–132 bpm |
| 70 | 95–111 bpm | 87–101 bpm | 90–105 bpm | 119–129 bpm |
| 75 | 93–109 bpm | 84–98 bpm | 87–102 bpm | 117–127 bpm |
| 80 | 91–106 bpm | 81–95 bpm | 84–98 bpm | 115–124 bpm |
How to check you are really in Zone 2
Talk test
You can speak in full sentences and breathe through your nose. If you can only say a few words at a time, ease off.
Heart rate
A chest strap is more reliable than a wrist sensor, which can latch on to your running cadence.
Heat & hills
Heart rate rises in the heat and on climbs. Slow down or walk to stay in the zone — that is normal.
Lab testing
A lactate or gas-exchange test finds your true first threshold, which may differ from any formula.
How much Zone 2 training?
Research on endurance athletes consistently shows that the best performers spend most of their training time — often around 75–80 % — at low intensity, with a smaller amount of hard training. For recreational runners, a practical template is three or four easy Zone 2 runs a week, including one longer run, plus one harder session.
Be patient. Many runners find Zone 2 frustratingly slow at first and have to walk hills. Your pace at the same heart rate typically improves over 8–12 weeks of consistent easy running. Track your pace at a fixed Zone 2 heart rate each month to see progress.
Zone 2 vs MAF vs the other zones
The MAF method uses a single ceiling of 180 minus your age, with adjustments; it usually lands near the top of Zone 2. See the MAF heart rate calculator for your number, and the heart rate zone calculator for all five zones. Want to know how your aerobic fitness compares? Try the VO2max calculator.
- Tanaka H, Monahan KD, Seals DR (2001). Age-predicted maximal heart rate revisited. J Am Coll Cardiol 37(1):153–156.
- Gulati M et al. (2010). Heart rate response to exercise stress testing in asymptomatic women. Circulation 122(2):130–137.
- San-Millán I, Brooks GA (2018). Assessment of metabolic flexibility by means of measuring blood lactate, fat, and carbohydrate oxidation responses to exercise in professional endurance athletes and less-fit individuals. Sports Med 48(2):467–479.
- Seiler S (2010). What is best practice for training intensity and duration distribution in endurance athletes? Int J Sports Physiol Perform 5(3):276–291.
Last reviewed: September 2026 · Health disclaimer