What PAL means
Physical activity level (PAL) is your total energy use over a day divided by your basal metabolic rate (BMR). A PAL of 1.6 means you burn 1.6 times your BMR. FAO, WHO and the United Nations University use PAL to set energy needs, and it plays the same role as the activity multiplier on a TDEE calculator.
How it's calculated
PAL = Σ (hours × PAR) ÷ 24
The second line is the FAO/WHO/UNU factorial method. Each activity has a physical activity ratio (PAR), its energy cost as a multiple of BMR. Multiply each PAR by the hours spent, add them up and divide by 24. The PAR values above come from Table 5.1 of the 2004 report. Exercise uses a MET value from the 2024 Adult Compendium of Physical Activities, spread over the week (hours per week ÷ 7).
Worked example
The FAO's own sedentary example: 8 h sleep × 1.0, 1 h personal care × 2.3, 1 h eating × 1.5, 1 h cooking × 2.1, 8 h sitting work × 1.5, 1 h housework × 2.8, 1 h driving × 2.0, 1 h walking × 3.2 and 2 h light leisure × 1.4. That adds up to 36.7, and 36.7 ÷ 24 = 1.53. These are the calculator's starting values.
Add 3 hours a week of running at 6 mph (9.3 MET): that's 3 ÷ 7 = 0.43 h a day, taken out of light leisure, so the total rises by 0.43 × (9.3 − 1.4) = 3.39, to 40.09. PAL = 40.09 ÷ 24 = 1.67.
FAO/WHO/UNU lifestyle categories
| Lifestyle | PAL |
|---|---|
| Sedentary or light activity | 1.40–1.69 |
| Active or moderately active | 1.70–1.99 |
| Vigorous or vigorously active | 2.00–2.40 |
The report notes that PAL values above 2.40 are hard to keep up for a long time.
PAR values used
| Activity (FAO Table 5.1) | PAR |
|---|---|
| Sleeping | 1 |
| Personal care (dressing, showering) | 2.3 |
| Eating | 1.5 |
| Cooking, food preparation | 2.1 |
| Sitting work (office, desk) | 1.5 |
| Standing work with light loads | 2.2 |
| General housework | 2.8 |
| Driving a car | 2 |
| Walking, varying pace | 3.2 |
| Light leisure (TV, conversation) | 1.4 |
| Low-intensity aerobic exercise | 4.2 |
Limitations
- METs and PARs aren't quite the same. A Compendium MET is a multiple of a fixed resting rate of 3.5 mL of oxygen per kg per minute. A PAR is a multiple of your own BMR. This calculator treats them as equal, which is an approximation. The Compendium notes that the fixed value can misjudge people whose resting rate differs from it.
- PAR values are averages for typical adults doing typical versions of each task.
- Your hours are guesses. Most people overestimate exercise time and underestimate sitting.
- If you use the TDEE ÷ BMR mode, the PAL can only be as good as those two numbers.