Background

Older adults are at risk of multiple chronic diseases, most of which could be prevented by engaging in regular physical activity. Frailty is a state of increased vulnerability to diseases. Worsening symptoms of frailty, such as decrease in physical functionality, can compromise health-related quality of life (HR-QOL). Previous findings suggest that frailty moderates the relationship between physical activity and HR-QOL, yet intervention findings are limited, particularly in dose-response analyses. Hence, this study was conducted to test if lower-dose physical activity (120 minutes/week) would provide the same benefits in health outcomes (physical functionality and HR-QOL) as higher-dose physical activity (180 minutes/week).

Methods

Participants (n=110) were older adults comprising higher-dose, lower-dose, and control groups who were combined from recent randomized controlled trials. Experimental groups participated in a multimodal exercise program in a supervised laboratory setting for 12 weeks.

Results

The higher-dose group showed a significant improvement in physical functionality (β=0.23, P=0.03) and in overall HR-QOL (β=0.44, P=0.001) including its subcategories over the control group. A group × frailty interaction revealed that frail individuals significantly improved in capacity HR-QOL when they exercised at a higher dose (F (1, 49)=4.57, P=0.038).

Conclusion

This study identifies a positive, predictive relationship between exercise duration and health outcomes (HR-QOL dimensions and frailty) among older adults. Frail individuals in the higher-dose group demonstrated significant recovery of capacity HR-QOL, thus reflecting improvement in their daily activities.

Introduction

Physical exercise and cognitive training have the potential to enhance cognitive function and mobility in older adults at risk of Alzheimer's disease and related dementia (ADRD), but little is known about the feasibility of delivering multidomain interventions in home settings of older adults at risk of ADRD. This study aims to assess the feasibility of home-based delivery of exercise and cognitive interventions, and to evaluate the relationship between participants' intervention preferences and their subsequent adherence. Secondary objectives include the effect of the interventions on ADRD risk factors, including frailty, mobility, sleep, diet and psychological health.

Methods and analysis

The SYNchronising Exercises, Remedies in GaIt and Cognition at Home (SYNERGIC@Home) feasibility trial is a randomised control trial that follows a 2×2 factorial design, with a 16-week home-based intervention programme (3 sessions per week) of physical exercises and cognitive training. Participants will be randomised in blocks of four to one of the following four arms: (1) combined exercise (aerobic and resistance)+cognitive training (NEUROPEAK); (2) combined exercise+control cognitive training (web searching); (3) control exercise (balance and toning)+cognitive training; and (4) control exercise+control cognitive training. SYNERGIC@Home will be implemented through video conferencing. Baseline and post-intervention assessments at 4-month and 10-month follow-up will include measures of cognition, frailty, mobility, sleep, diet and psychological health. Primary feasibility outcome is adherence to the interventions. Primary analytic outcome is the relationship between pre-allocation preference for a given intervention and subsequent adherence to the allocated intervention. A series of secondary analytic outcomes examining the potential effect of the individual and combined interventions on cognitive, mobility and general well-being will be measured at baseline and follow-up.

Ethics and dissemination

Ethics approval was granted by the relevant research ethics boards. Findings of the study will be presented to stakeholders and published in peer-reviewed journals and at provincial, national and international conferences.

Trial registration number

NCT04997681, Pre-results.