Heart-rate zones
Five training zones from your max heart rate. Add your resting heart rate if you know it — the zones then use heart-rate reserve (Karvonen), which fits most people a little better.
Don't know your max? A rough starting guess is 208 − 0.7 × your age
| Zone | Beats/min | What it's for |
|---|
Where it bends: an age-based maximum describes the average of a large group, and individuals sit around that average rather than on it — so yours can be some way off. Zone borders are conveniences too, not laws of physiology. If your easy runs don't feel easy in "easy" numbers, trust the feeling and test properly — a hard hill session or a lab test beats any formula.
Under the hood
Two different sums, depending on what you tell it. Give it only your maximum heart rate and each zone is a straight percentage of that. Add your resting rate and it switches to your heart-rate reserve — the room between resting and maximum — which is the sum most coaches use, because it accounts for the fact that your heart never drops to zero.
Without one
zone edge = percentage × maximum
That first line is often called the Karvonen method. It is worth knowing that this is a definition rather than a discovery: "percentage of your reserve" simply means that sum. Nothing was measured to arrive at it.
The numbers that go in
| Number | What it is | Where it comes from |
|---|---|---|
| 208 − 0.7 × age | the estimate behind the "guess my max" button | Tanaka, Monahan & Seals (2001): a pooled analysis of 351 studies and 18,712 people, checked again in a lab on 514 more. Their line did not differ between men and women, or by how much people trained. |
| 50 · 60 · 70 · 80 · 90 · 100% | the five zone edges | A convention, not a finding. Zone models are a way of talking about intensity; the boundaries are round numbers that different systems place differently. |
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