Target Heart Rate (the Karvonen Method)

Finds the target heart rate as (maximum − resting) × intensity + resting. The maximum is estimated as 220 minus your age.

Explanation

This is the heart rate to aim for when you want to train at a chosen intensity. The Karvonen method gives it.

\text{target} = (\text{maximum} - \text{resting}) \times \text{intensity} + \text{resting}

\text{maximum} = 220 - \text{age}

Example

A 30-year-old with a resting pulse of 60 wants to train at 60% intensity.

\text{maximum} = 220 - 30 = 190

(190 - 60) \times 0.6 + 60 = 78 + 60 = 138\ \text{bpm}

So 138 beats per minute is the number to hold.

What each zone is for

50 to 60% — warm-up and fat burning
60 to 70% — fat burning plus endurance, the sweet spot for most people
70 to 80% — building cardiovascular fitness
Above 80% — competitive training, not sustainable for long

Why subtract the resting rate

Taking a plain 60% of the maximum gives $190 \times 0.6 = 114$ — suspiciously low.

And it should be, because the heart is already beating 60 times a minute while you sit still. If you want to measure how hard you are making it work, the yardstick has to be the reserve between resting and maximum, not the maximum alone.

Karvonen uses that reserve, so "60% intensity" feels the same to a trained athlete resting at 50 as it does to someone resting at 80.

Watch out

The formula $220 - \text{age}$ is a rough rule of thumb. Real maximum heart rates at any given age scatter by ten beats or more either way.

Anyone with heart disease, and anyone on medication — beta blockers in particular hold the pulse down — cannot use this formula as it stands. Follow medical advice instead.