Zone 2 at age 23 explained
Zone 2 is easy, conversational aerobic exercise — the intensity that builds endurance with little fatigue. It is usually defined as 60–70 % of maximum heart rate. Because max heart rate falls with age, so does the Zone 2 range. At 23, the Tanaka equation estimates a man’s max heart rate at 192 bpm and the Gulati equation estimates a woman’s at 186 bpm, giving the ranges above.
Individual max heart rates vary by 10–15 beats around these estimates, so treat them as a starting point. If your breathing feels laboured or you cannot speak in full sentences at the top of the range, you are probably above your personal Zone 2.
All five heart rate zones at 23
| Zone | % max HR | Men | Women |
|---|---|---|---|
| Z1 Recovery | 50–60 % | 96–115 bpm | 93–111 bpm |
| Z2 Aerobic / Easy | 60–70 % | 115–134 bpm | 111–130 bpm |
| Z3 Tempo | 70–80 % | 134–154 bpm | 130–149 bpm |
| Z4 Threshold | 80–90 % | 154–173 bpm | 149–167 bpm |
| Z5 VO2max | 90–100 % | 173–192 bpm | 167–186 bpm |
Zone 2 by resting heart rate (Karvonen)
The Karvonen method uses your heart rate reserve (max minus resting), which accounts for fitness. Find your resting heart rate — measured in bed on waking — in the left column:
| Resting HR | Men (Zone 2) | Women (Zone 2) |
|---|---|---|
| 50 bpm | 135–149 bpm | 131–145 bpm |
| 55 bpm | 137–151 bpm | 133–147 bpm |
| 60 bpm | 139–152 bpm | 135–148 bpm |
| 65 bpm | 141–154 bpm | 137–150 bpm |
| 70 bpm | 143–155 bpm | 139–151 bpm |
| 75 bpm | 145–157 bpm | 141–153 bpm |
How to train in Zone 2 at 23
- Make most runs easy: for most runners, three or four Zone 2 sessions a week plus one harder session is a sound structure.
- Go by effort on hot days and hills: heart rate rises with heat and gradient, so slow down or walk to stay in range.
- Track progress: note your pace at the middle of your Zone 2 range once a month — it should get faster as aerobic fitness improves.
- Be patient: Zone 2 often feels slow at first; improvements usually show within 8–12 weeks.
Health first. If you have a heart condition, take medication that affects heart rate (such as beta-blockers), or are new to exercise, ask your doctor which heart rate range is right for you.
Zone 2 at nearby ages
Formulas: Tanaka et al. (2001), Gulati et al. (2010), Karvonen et al. (1957). Last reviewed September 2026. Health disclaimer