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Relationships between physical activity, sleep and cognitive function: A narrative review
Sewell KR, Erickson KI, Rainey-Smith SR, Peiffer JJ, Sohrabi HR, Brown BM.. Neuroscience and biobehavioral reviews, 2021-09-11
Topic: Risk, prevention and care in population studies
Physical activity and exercise can improve cognitive function and reduce the risk for dementia. Other lifestyle factors, including sleep, are associated with cognitive function and dementia risk, and exercise is an effective therapeutic strategy for improving sleep. Based on these associations, it has been hypothesised that sleep might be an important mediator for the effects of exercise on cognition. Here, we review the current literature to evaluate whether sleep and physical activity are independently or jointly associated with cognitive function. The extant literature in this area is minimal, and the causal relationships between physical activity, sleep and cognition have not been examined. A small number of cross-sectional studies in this area suggest that physical activity may attenuate some of the negative impact that poor sleep has on cognition, and also that sleep may be a mechanism through which physical activity improves cognitive abilities. Further research may enable the development of individually tailored intervention programs to result in the greatest cognitive benefit, ultimately delaying the onset of Alzheimer's disease.
Key findings
- Other lifestyle factors, including sleep, are associated with cognitive function and dementia risk, and exercise is an effective therapeutic strategy for improving sleep.
- Here, we review the current literature to evaluate whether sleep and physical activity are independently or jointly associated with cognitive function.
- A small number of cross-sectional studies in this area suggest that physical activity may attenuate some of the negative impact that poor sleep has on cognition, and also that sleep may be a mechanism through which physical activity improves cognitive abilities.
- Further research may enable the development of individually tailored intervention programs to result in the greatest cognitive benefit, ultimately delaying the onset of Alzheimer's disease.
Why it matters
This narrative review reports that physical activity can improve cognitive function and reduce dementia risk, that exercise improves sleep, and that a small number of cross-sectional studies suggest sleep may mediate some effects of activity on cognition. It states that the literature is minimal and causal relationships have not been examined, so no firm prevention recommendation can be drawn.
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Study details
- Study designcross-sectional
- Evidence strengthLow
How this study scored 52/100
Published in a peer-reviewed journal, and it is a snapshot of people at one point in time. Scored zero for sample size, effect reported, studied in people and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Neuroscience and biobehavioral reviews) |
| Journal's citation record | 3 / 4 | Neuroscience & Biobehavioral Reviews: journal h-index 375 (OpenAlex, 2026-10-29) |
| Study design | 4 / 12 | A snapshot of people at one point in time |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 3 / 5 | 2021 — within 6 year(s) of the newest study here |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 5 / 7 | Cited 173 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 24.7 citations a year over 7 year(s) since 2021 |
| Impact for its field and year | 3 / 6 | Cited 4.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 2 / 6 | Cited by 3 other studies in this library |
| Still being cited | 3 / 4 | Cited 133 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Belinda M. Brown: h-index 36 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | University of Pittsburgh: institution h-index 1,470 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 6 institution(s) in 2 countries |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 34506842) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 52 / 100 | — |
What each of these 20 components measures, and what this score is not →
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Sewell, K. R., Erickson, K. I., Rainey-Smith, SR., Peiffer, J. J., Sohrabi, H. R., & Brown, B. M. (2021). Relationships between physical activity, sleep and cognitive function: A narrative review. Neuroscience and biobehavioral reviews. https://doi.org/10.1016/j.neubiorev.2021.09.003
Vancouver
Sewell KR, Erickson KI, Rainey-Smith SR, Peiffer JJ, Sohrabi HR, Brown BM. Relationships between physical activity, sleep and cognitive function: A narrative review. Neuroscience and biobehavioral reviews. 2021. doi:10.1016/j.neubiorev.2021.09.003. PMID: 34506842.
BibTeX
@article{sewell2021-34506842,
author = {Sewell, K. R. and Erickson, K. I. and Rainey-Smith, SR. and Peiffer, J. J. and Sohrabi, H. R. and Brown, B. M.},
title = {{Relationships between physical activity, sleep and cognitive function: A narrative review}},
journal = {Neuroscience and biobehavioral reviews},
year = {2021},
doi = {10.1016/j.neubiorev.2021.09.003},
pmid = {34506842},
url = {https://doi.org/10.1016/j.neubiorev.2021.09.003}
}
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