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Physical activity and cognitive functioning in the oldest old: within- and between-person cognitive activity and psychosocial mediators

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Abstract

The current study examines the role of social contact intensity, cognitive activity, and depressive symptoms as within- and between-person mediators for the relationships between physical activity and cognitive functioning. All three types of mediators were considered simultaneously using multilevel structural equations modeling with longitudinal data. The sample consisted of 470 adults ranging from 79.37 to 97.92 years of age (M = 83.4; SD = 3.2) at the first occasion. Between-person differences in cognitive activity mediated the relationship between physical activity and cognitive functioning, such that individuals who participated in more physical activities, on average, engaged in more cognitive activities and, in turn, showed better cognitive functioning. Mediation of between-person associations between physical activity and memory through social contact intensity was also significant. At the within-person level, only cognitive activity mediated the relationship between physical activity and change in cognition; however, the indirect effect was small. Depressive symptomatology was not found to significantly mediate within- or between-person effects on cognitive change. Our findings highlight the implications of physical activity participation for the prevention of cognitive decline and the importance of meditational processes at the between-person level. Physical activity can provide older adults with an avenue to make new friendships and engage in more cognitive activities which, in turn, attenuates cognitive decline.

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Acknowledgments

This research was supported by NIH Grant AG026453. The OCTO-Twin study was funded by the National Institute on Aging at the National Institutes of Health (Grant number AG08861), The Swedish Council for Working Life and Social Research, The Adlerbertska Foundation, The Hjalmar Svensson Foundation, The Knut and Alice Wallenberg Foundation, The Wenner-Gren Foundations, and The Wilhelm and Martina Lundgrens Foundation, and the Swedish Brain Power Consortium.

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Robitaille, A., Muniz, G., Lindwall, M. et al. Physical activity and cognitive functioning in the oldest old: within- and between-person cognitive activity and psychosocial mediators. Eur J Ageing 11, 333–347 (2014). https://doi.org/10.1007/s10433-014-0314-z

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