How does physical activity benefit people living with dementia? A systematic review to identify the potential mechanisms of action

Abstract

Purpose One limitation of research that assesses the effectiveness of physical activity interventions for people with dementia is that most do not describe the intervention in sufficient detail to ascertain a theoretical basis or mechanism of action that determines the effective components. This paper aims to identify studies which evaluate the mechanisms of action of physical activity interventions for people with dementia, to further inform effective intervention development. Design/methodology/approach Papers were screened for evidence of evaluation of specific forms of physical activity, using pre-defined inclusion criteria. Analysis was conducted to ascertain if mechanisms of action were corroborated by data within and between studies. Findings The authors identified 26 studies with a measured mechanism of action; these related to the effects of physical activity on either neurological structure or endocrinal markers, including hormones. Physical activity had potential to reduce hippocampal atrophy, increase neural recruitment, activate the noradrenergic system and improve anti-inflammatory responses. While individual studies were hampered by small sample sizes, the body of evidence indicated that physical activity may have potential to delay cognitive decline. Practical implications Mechanisms of action in relation to dementia and physical activity are likely to be multifaceted, and physical activity may be protective against progression in the early stages of cognitive decline. Physical activity may be of greatest benefit if incorporated into on-going lifestyle, rather than engaged in for short periods, and combined with social interaction. Originality/value This paper is unique in its focus on the mechanisms of action of physical activity interventions for people with dementia.

Does Therapeutic Exercise Support Improvement in Cognitive Function and Instrumental Activities of Daily Living in Patients with Mild Alzheimer’s Disease? A Randomized Controlled Trial

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“We Can Do This!”: The Role of Physical Activity in What Comes Next for Dementia

“…There is increasing and global interest in what physical activity can offer to people living with dementia [23] because of its contributions in several different ways; for example, via potentially averting, holding up or improving symptoms of dementia [24,25], with evidence that suitable interventions may slacken the rate of disease progression [26]. In addition, within the field of dementia reminiscence, physical activity has been employed to stimulate memories of times past in the lives of individuals; for example, through use of Irish dancing [27].…”

Sport for confidence: a collaborative programme of physical activity, sport and exercise for people with Young Onset Dementia

“…The article cannot do justice to the abundant research demonstrating the value of physical and social activity in preventing, delaying or improving symptoms of dementia (Livingston et al , 2017; Lewis et al , 2020; Pringle et al , 2021). There is a growing body of evidence, mostly from China, Korea, Taiwan and Japan, on the positive impact of exercise on dementia (Chen et al , 2020).…”

“…What is evident is that exercise is more effective if started early, right for the individual, socially interactive, regular and enjoyable. Importantly, there is no evidence of harm, and therefore, no reason to wait while further research is undertaken (Lewis et al , 2020; Pringle et al , 2021).…”