Effects of a home-based exercise and physical activity intervention after inpatient rehabilitation on real-world mobility in older adults with cognitive impairment: a secondary analysis of a randomised controlled trial

Background: Persistent mobility limitations after inpatient rehabilitation are common in older adults with cognitive impairment (CI). Home-based exercise interventions can improve locomotor capacity during this vulnerable period; however, evidence that they improve real-world mobility is scarce. Objective: To investigate the effects of a home-based exercise programme combined with physical activity (PA) promotion on real-world digital mobility outcomes (DMOs). Design: Single-centre, double-blind, randomised, placebo-controlled trial. Setting: Community. Participants: 104 community-dwelling older adults with CI (82.3 ± 6.0 years; 75% women; Mini-Mental State Examination score 23.2 ± 2.4) recently discharged from inpatient geriatric rehabilitation. Methods: The intervention group received a 12-week home-based exercise programme combined with behavioural change techniques to promote PA; the control group received a 12-week non-specific home-based placebo motor activity programme. DMOs related to walking amount, pattern and pace were measured over 48 h at baseline, post-intervention and after a 12-week follow-up using a single body-fixed sensor and validated processing algorithms. Results: Post-intervention, small statistically significant improvements favouring the intervention group were observed in walking pattern and pace outcomes, including longer walking bout (WB) duration, higher walking speed and longer stride length in shorter (10–30 s) WBs, and higher 90^th percentile walking speed in WBs >10 s. These improvements were not sustained at the 12-week follow-up. No between-group differences were found for walking amount. Conclusion: The post-discharge home-based exercise programme combined with PA promotion showed small, short-term improvements in selected real-world walking pattern and pace outcomes in older adults with CI after inpatient rehabilitation; however, these effects were no longer evident at follow-up, and walking amount did not increase.