Physical activity frequency, intensity and duration (PAFID) questionnaire. Number, MET-values and minutes in parentheses in answering alternatives represents the values for the calculation of MET-hours per week
| Frequency (days) | Intensity (METs) | Duration (minutes) |
| How frequently do you exercise? With exercise, we mean walking, cross-country skiing, swimming or other exercise/sports. | On average, how hard is the exercise? | On average, how long do you exercise? |
| Never (0) | I take it easy without breaking into a sweat or losing my breath (3 METs) | <15 min (10 min) |
| Less than once a week (0.5) | I push myself so hard that I break into a sweat and lose my breath (6 METs) | 15–29 min (22.5 min) |
| Once a week (1) | I push myself to near-exhaustion (9 METs) | 30–60 min (45 min) |
| Two to three times per week (2.5) | N/A | >60 min (60 min) |
| Almost every day (5) | N/A | N/A |
METs, metabolic equivalents of tasks.