A Digitally Supported Outdoor Physical Activity Intervention for Mildly Frail Older Adults in Hong Kong

Official title

A Digitally Supported Outdoor Physical Activity Intervention for Mildly Frail Older Adults: a Hybrid Type 1 Effectiveness-Implementation Cluster Randomized Controlled Trial (OUTDOOR-FIT)

Overview

The aging population in Hong Kong is projected to reach 36.6% by 2046, with roughly 16.6% of older adults estimated to be mildly frail-a condition linked to higher risks of falls, hospitalization, and mortality. While physical activity (PA) is a key modifiable determinant of frailty, a major service gap exists for mildly frail older adults, who lack tailored support, resources, and long-term self-management programs. Although Hong Kong features over 440 public open spaces equipped with senior-friendly outdoor exercise facilities (OEFs), older adults often lack awareness and knowledge on how to utilize them safely for aerobic, strength, and balance training. Furthermore, existing PA interventions often overlook social-ecological perspectives and fail to optimize built environment resources or address digital literacy barriers to sustain long-term behavior change. To bridge these gaps, our team developed and preliminary-tested OUTDOOR-FIT, a complex, theory-driven, socio-ecological mHealth intervention. OUTDOOR-FIT synergizes Hong Kong's built environment (OEFs), social and volunteer support, individual goal-setting, and digital health technology (a contextually tailored mobile Application) to empower mildly frail older adults to self-manage their PA habits. Building upon promising preliminary findings and qualitative feedback from our initial pilot RCT, the intervention has been refined to incorporate neighborhood OEF environmental audits, supervised outdoor experiential practice sessions, and a train-the-trainer volunteer model to support digital literacy and engagement. The main objective of this study is to evaluate the clinical effectiveness and real-world implementation of the refined OUTDOOR-FIT intervention using a hybrid type 1 effectiveness-implementation design. Primary effectiveness outcomes include physical activity levels, exercise self-efficacy, mental well-being, chronic pain, and social loneliness measured immediately post-intervention, as well as at 3-month and 6-month follow-ups. Guided by the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework, secondary implementation outcomes include Reach, Effectiveness, Adoption, Implementation fidelity, and Organizational Maintenance. This study adopts a mixed-methods design embedded within a two-arm cluster randomized controlled trial (cluster RCT) involving community service units. Mildly frail older adults will be cluster-randomized into either (i) the OUTDOOR-FIT intervention group or (ii) a control group. Quantitative analysis will be conducted to evaluate the immediate and sustained effectiveness of the intervention across the primary health outcomes. The qualitative component will consist of semi-structured interviews with older adult participants and community stakeholders to evaluate intervention adoption, implementation barriers, and long-term organizational maintenance.

Interventions

• Behavioral OUTDOOR-FIT
  Participants in the intervention group will undergo four weekly educational workshops (once per week), with 1 hour duration led by exercise specialists (i.e., certified personal trainer, kinesiologist, degree in exercise or health sciences), and support by volunteers and mobile application (app). Two of these workshops will include two sessions of senior-friendly OEFs visits. The rest of the workshops will cover various topics including introduction of the app, risk management for exercising out
• Behavioral Active Control
  Participants in the active control group will engage in four weekly health education workshops, each lasting for 60 minutes and including exercise experiential sessions. The workshops will be led by exercise specialists (i.e., certified personal trainer, kinesiologist, degree in exercise or health sciences). The workshops focus on the benefits of different exercises for older adults, particularly older adults with mild frailty. Participants have opportunities to experience different modified exe

Primary outcome measures

• Physical Activity Level [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]

Secondary outcome measures (7)

• Exercise Self-Efficacy [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]
• Mental Well-Being [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]
• Pain Severity [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]
• Social Loneliness [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]
• Organizational Readiness for Adoption [Time frame: Baseline]
• Implementation Fidelity [Time frame: Baseline, immediately post-intervention (Month 1)]
• Organizational Intention to Maintain [Time frame: Baseline, immediately post-intervention (Month 1), 3 months post-intervention (Month 4), and 6 months post-intervention (Month 7)]

Eligibility criteria

Inclusion criteria

• community-dwelling men or women aged 60 years or over
• self-report of mild frailty as determined by a score of ≥ 1 and ≤ 3 on the Chinese version of the Fatigue, Resistance, Ambulation, Illness, and Loss of Weight (FRAIL) scale
• passing the Physical Activity Readiness- Questionnaire (PAR-Q)
• owning a smart phone for daily use
• signing the informed consent documents

Exclusion criteria

• older adult participants who achieved adequate level of daily physical activity, as defined as engaging in moderate-to-vigorous intensity physical activity (MVPA) for at least 150 minutes per week
• scoring 0 or 4/5 in the FRAIL scale
• mildly frail older adults without cognitive ability to respond to self-reported questionnaires

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Supportive care

Study locations

Hong Kong · 1 center

• Department of Rehabilitation Sciences, The Hong Kong Polytechnic University — Hong Kong

Identifiers

NCT: NCT07752615 · P0056261

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗