The MAF 180 Formula explained
The MAF 180 Formula, developed by Dr Phil Maffetone, is one of the simplest ways to set an aerobic training heart rate. It gives a single number to stay at or below, adjusted for your health and training history.
The formula
The result is a ceiling: Maffetone describes exceeding it as a rapid transition towards anaerobic work. Train at or below it.
MAF heart rate chart
| Age | (a) −10 | (b) −5 | (c) no change | (d) +5 |
|---|---|---|---|---|
| 25 | 145 | 150 | 155 | 160 |
| 35 | 135 | 140 | 145 | 150 |
| 45 | 125 | 130 | 135 | 140 |
| 55 | 115 | 120 | 125 | 130 |
| 65 | 105 | 110 | 115 | 120 |
Special cases
- Over 65: Maffetone notes the formula may need further individualising; for some people in category (d) only, up to 10 beats may be added — but not automatically.
- 16 and under: the formula does not apply. Maffetone suggests a heart rate of 165 for this group.
- Medication: anyone on regular medication falls in category (a) — and should also check with their doctor, as some drugs change heart rate response.
How MAF compares with other methods
MAF is not derived from maximum heart rate, so it does not inherit the errors of age-based maximum formulas. It is deliberately conservative for people who are ill, injured or inconsistent. For a healthy, consistently training 40-year-old, the MAF figure of 140 bpm sits near the top of a typical Karvonen Zone 2 range. Compare all methods for your own numbers in the calculator.
Using MAF in practice
- Set your heart rate monitor alarm at your MAF number.
- Expect to slow down at first — sometimes a lot. Walking breaks on hills are normal.
- Track your pace at the same heart rate over weeks (Maffetone calls this the "MAF Test"). A faster pace at the same heart rate indicates improving aerobic fitness.
Frequently asked questions
Is the MAF heart rate a range or a single number?
Maffetone presents it as a single number: the maximum aerobic heart rate. Train at or below it. Many people naturally train a few beats below the ceiling to allow for drift.
Why is MAF lower than other methods for some people?
The adjustments deliberately lower the ceiling for people who are ill, injured, on medication or training inconsistently, to keep training aerobic and recovery-friendly.
What is a MAF Test?
A regular check, often monthly, of your pace or power at your MAF heart rate over a fixed distance or time. If you go faster at the same heart rate, your aerobic fitness is improving.
Medical note: This is general information, not medical advice. Heart rate formulas are estimates. If you have a heart condition, high blood pressure, diabetes, take medication that affects heart rate (such as beta-blockers), are pregnant, or are new to exercise, ask a doctor before changing your training. Stop and seek help if you feel chest pain, severe breathlessness, dizziness or palpitations. Full disclaimer.
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