Descriptive characteristics of the analytical full sample
| Max n | n (%) | 1531 (100%) |
| Sex | Female (%) | 53 |
| Leisure time physical activity participation | ||
| Physical activity at age 36 | None (%) | 33 |
| Moderate activity: 1–4 times/month (%) | 27 | |
| Most activity: ≥5 times/month (%) | 40 | |
| Physical activity at age 43 | None (%) | 47 |
| Moderate activity: 1–4 times/month (%) | 25 | |
| Most activity: ≥5 times/month (%) | 28 | |
| Physical activity at age 53 | None (%) | 42 |
| Moderate activity: 1–4 times/month (%) | 21 | |
| Most activity: ≥5 times/month (%) | 37 | |
| Physical activity at ages 60–64 | None (%) | 61 |
| Moderate activity: 1–4 times/month (%) | 15 | |
| Most activity: ≥5 times/month (%) | 24 | |
| Physical activity at age 69 | None (%) | 56 |
| Moderate activity: 1–4 times/month (%) | 14 | |
| Most activity: ≥5 times/month (%) | 30 | |
| Physical activity, accumulative across five time periods | Never active | 11 |
| Active at one time period (%) | 17 | |
| Active at two time periods (%) | 20 | |
| Active at three time periods (%) | 20 | |
| Active at four time periods (%) | 17 | |
| Active at all five time periods (%) | 15 | |
| Cognitive function, age 69 | ||
| ACE-III total scores at age 69 | Mean (SD) | 92 (6.2) |
| Word learning test (WLT) score at age 69 | Mean (SD) | 22.5 (5.8) |
| Visual Search Speed score at age 69 | Mean (SD) | 261.6 (71.8) |
| Covariables | ||
| Cognition score at age 8 (standardised*) | Mean (SD) | 0.17 (7.8) |
| Childhood socioeconomic position | Manual (%) | 51 |
| Non-manual (%) | 49 | |
| Highest educational attainment up to age 26 | None attempted (%) | 28 |
| Vocational or GCSE (%) | 29 | |
| A-level or higher (%) | 43 | |
| Framingham Risk Score at age 69 | Median %, (IQR) | 24.9 (14.0) |
| Mental health caseness at age 69 | Yes (%) | 13 |
| APOE-ε4 | APOE ε4 non-carriers (%) | 70 |
| APOE ε4 carriers (%) | 30 | |
The analytical sample required complete physical activity data at 5 time periods and at least one available cognitive function measure at age 69.
*Standardised to the available sample at age 8 (n=4256).
ACE-III, Addenbrooke’s Cognitive Examination-III; GCSE, General Certificate of Secondary Education; NSHD, National Survey of Health and Development.