Improves cognitive function
A recent meta-analysis of prospective studies has reported a protective effect for physical activity in all-cause dementia – incidence of dementia was reduced by 21% in those who undertook high levels of physical activity, and by 24% with moderate levels. Greater benefit was seen in Alzheimer’s Disease (37% risk reduction with high levels of activity, 29% with moderate levels), but no protective effect was observed in vascular dementia (although this finding may have been limited by a smaller sample size) (1). Another systematic review reported that physical activity conveys a mild positive effect on cognition but was not able to observe a dose-response relationship (2). This finding has not always been observed in the oldest age groups – a population-based cohort study of over-75s demonstrated no significant effect of physical inactivity and risk of severe cognitive impairment or dementia (3). Physical activity in mid-life has been associated with positive ageing outcomes, including the absence of cognitive impairment or mental health limitations (4).
A retrospective study of individuals with a family history of Alzheimer’s Disease (≥1 affected relative), showed greater cognitive function in those who met recommended physical activity guidelines, compared to those who were inactive (5). There is increasing evidence that higher levels of physical activity may be associated with reduced risk of cognitive decline, but such conclusions are limited by a large variability in study design, differences in assessment of cognition/definitions of dementia and use of self-reported levels of physical activity.
Quality of evidence
Strength of recommendation
- Impact of Physical Activity on Cognitive Decline, Dementia, and Its Subtypes: Meta-Analysis of Prospective Studies.
Biomed Res Int. 2017;2017:9016924. Epub 2017 Feb 7.
- Physical Activity in Community Dwelling Older People: A Systematic Review of Reviews of Interventions and Context.
PLoS One. 2016 Dec 20;11(12):e0168614.
- Lack of associations between modifiable risk factors and dementia in the very old: findings from the Cambridge City over-75s cohort study.
Aging Ment Health. 2017 Feb 2:1-7. [Epub ahead of print]
- Behavioural Risk Factors in Mid-Life Associated with Successful Ageing, Disability, Dementia and Frailty in Later Life: A Rapid Systematic Review.
PLoS One. 2016 Feb 4;11(2):e0144405. eCollection 2016.
- Physical activity is associated with higher cognitive function among adults at risk for Alzheimer’s disease.
Complement Ther Med. 2018 Feb;36:46-49. Epub 2017 Nov 24.