Question 1

What is my Zone 2 heart rate for my age?

Accepted Answer

Using the Tanaka formula (208 − 0.7 × age), estimated Zone 2 ranges are: age 20, 116–136 bpm on the 5-zone model and 136–155 bpm at 70–80% of max; age 25, 115–134 bpm on the 5-zone model and 134–153 bpm at 70–80% of max; age 30, 112–131 bpm on the 5-zone model and 131–150 bpm at 70–80% of max; age 35, 110–129 bpm on the 5-zone model and 129–147 bpm at 70–80% of max; age 40, 108–126 bpm on the 5-zone model and 126–144 bpm at 70–80% of max; age 45, 106–124 bpm on the 5-zone model and 124–142 bpm at 70–80% of max; age 50, 104–121 bpm on the 5-zone model and 121–138 bpm at 70–80% of max; age 55, 102–119 bpm on the 5-zone model and 119–136 bpm at 70–80% of max; age 60, 100–116 bpm on the 5-zone model and 116–133 bpm at 70–80% of max; age 65, 98–114 bpm on the 5-zone model and 114–130 bpm at 70–80% of max; age 70, 95–111 bpm on the 5-zone model and 111–127 bpm at 70–80% of max; age 75, 94–109 bpm on the 5-zone model and 109–125 bpm at 70–80% of max. These are population estimates, not your measured max.

Question 2

What is Zone 2 heart rate for a 40 year old?

Accepted Answer

For a 40 year old, estimated maximum heart rate is 180 bpm by the Tanaka formula. That puts Zone 2 at 108–126 bpm on the conventional 5-zone model, or 126–144 bpm if you use the 70–80%-of-max definition. The two models disagree by roughly 18 beats at the top end.

Question 3

Why do my watch and my coach disagree about Zone 2?

Accepted Answer

Because they are using different zone models against the same estimated maximum. The conventional 5-zone model most watches ship with puts Zone 2 at 60–70% of max heart rate; a 70–80%-of-max definition is also in common use. At age 50 that is the difference between 104–121 and 121–138 bpm. Neither is wrong; they are different conventions.

Question 4

How do I find Zone 2 without a heart rate monitor?

Accepted Answer

Use the talk test, which Attia, Huberman and Patrick all endorse: at Zone 2 you can speak in complete sentences but with noticeable strain — the other person can tell you are exercising. Peter Attia's stricter version is that you can maintain nasal breathing but would prefer not to talk. The formal definition Attia uses is blood lactate below 2 mmol/L, which no heart rate formula can estimate for you.

Zone 2 Heart Rate by Age

The short answer, at 40

Zone 2 heart rate by age

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No monitor? Use the talk test

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What 5 experts say about Zone 2

How this is calculated

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Age	Max HR	Zone 2 · 60–70%	Zone 2 · 70–80%
20	194	116–136	136–155
25	191	115–134	134–153
30	187	112–131	131–150
35	184	110–129	129–147
40	180	108–126	126–144
45	177	106–124	124–142
50	173	104–121	121–138
55	170	102–119	119–136
60	166	100–116	116–133
65	163	98–114	114–130
70	159	95–111	111–127
75	156	94–109	109–125