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Systematic review and meta-analysis investigating moderators of long-term effects of exercise on cognition in healthy individuals

Abstract

As cognitive function is linked with academic achievement, career success and mental health, there is a need to understand how the cognitive benefits of long-term exercise can be optimized. Our meta-regression included 80 randomized controlled trials and examined moderators of the effects of exercise on cognition in healthy individuals. The summary effect was small and did not differ between cognitive domains. Higher benefits of exercise on cognitive function were found after coordinative exercise compared with other exercise types. With longer intervention length, the effect size increased with longer session duration. Exercise was less effective in female compared with male individuals, and the dose–response relationship differed between sexes. Our findings suggest a general rather than domain-specific effect of exercise on cognition, which is influenced by sex, exercise type and reciprocal relationships between dose parameters. We derive sex-specific recommendations on how cognitive benefits can be optimized by exercise intensity, its progression and exercise type.

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Fig. 1: PRISMA flow diagram showing the results of the literature search.
Fig. 2: Funnel plot.
Fig. 3: Main effects of variables and their interactions on the effect of exercise on cognitive function.
Fig. 4: Effect of interactions on the effect of exercise on cognitive function.

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Data availability

Data are available from the corresponding author upon request. Our meta-regression used data from studies of different authors and some of them informed us that we must not share their original data due to regulations that apply for their ethics approval.

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Acknowledgements

We received no specific funding for this work. We thank F. Colledge for proofreading the manuscript.

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S.L., K.K. and U.P. planned the meta-regression and formulated the hypotheses. S.L., V.N.L. and K.K. performed the literature search and screening. S.L., V.N.L. and M.G. conducted the data extraction and coding, calculated the effect sizes and rated the quality. S.L. performed the statistical analyses. S.L. and K.K. drafted the initial version of the manuscript. All authors were involved in revisions of the draft.

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Correspondence to Sebastian Ludyga.

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Extended data

Extended Data Fig. 1 Forest plot.

Presented data are composite scores combining complex attention, executive function and memory within each study.

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Supplementary Tables 1–12 and formulae 1 and 2.

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Ludyga, S., Gerber, M., Pühse, U. et al. Systematic review and meta-analysis investigating moderators of long-term effects of exercise on cognition in healthy individuals. Nat Hum Behav 4, 603–612 (2020). https://doi.org/10.1038/s41562-020-0851-8

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