The REACT study
The REACT study
The REACT study
The REACT study
The REACT study

Scientific summary

Research Question:

What is the effectiveness and cost-effectiveness, compared with a minimal intervention control condition, of a community-based physical activity intervention (REACT) for reducing the progression of functional limitations in older people who are at high risk of mobility-related disability?


Modelled on the LIFE physical activity intervention for older people in the US, REACT is a standardised 12-month, primarily group-based physical activity programme with two phases: 1) Adoption (weeks 1 24) provides a 45-minute individual assessment, followed by two 60 minute sessions per week designed to stimulate initial increases in fitness, lower-limb function, confidence and social support and facilitate lifestyle changes; 2) Maintenance (weeks 25-52) provides an optional weekly exercise session. Participants are informed about local activity opportunities, offered taster session vouchers for various activities, and invited to become REACT Ambassadors to support the ongoing sustainability of REACT. The setting: Leisure/community centres and fitness/health clubs provided by REACT collaborators during low usage hours in economically and ethnically diverse areas.


Delivery staff:

Qualified exercise specialists will be trained to deliver the intervention. Funding: Intervention costs are covered by BANES City Council, the West Bank Charitable Organisation and AgeUK Birmingham.


Evaluation methods:

A multi-centre pragmatic two-arm parallel group randomised controlled trial with an internal pilot phase, and a 24 month follow-up, comparing REACT with a minimal intervention control condition. Participants: 768 sedentary men and women aged 65+ who are at risk of major mobility limitations but who are still ambulatory, will be randomised in a 1:1 ratio to either intervention or control group. Controls receive a minimal intervention comprising information about local activity opportunities and two education sessions on healthy ageing.



The primary outcome is functional ability (independently assessed performance on a sit-to-stand task, a standing balance test and gait speed), measured using the Short Physical Performance Battery (SPPB) at 24 months. The secondary outcome is minutes of moderate intensity physical activity, assessed by accelerometry. Tertiary outcomes include minutes of sedentary behaviour, health-related quality of life, cognitive function, mental well-being and the Barthel Index (an indicator of ability to live independently).


Health economics:

A full economic evaluation will estimate the incremental cost-effectiveness of REACT compared to control. Decision-analytic modelling will assess cost-effectiveness over a lifetime perspective.



Using intention-to-treat analysis of variance, REACT and the control groups will be compared at 24 months presented as between-group mean differences, 95% confidence intervals and p-values.

Public health impact:

Evidence-based, cost-effective interventions for preventing mobility disability in older people and tackling inactivity are needed to reduce health risks, particularly among people with low socio-economic status. Drawing on the latest, evidence-based intervention technology from the US and translating this for use in the UK has the potential to provide a timely response to this urgent problem.

To view the full scientific protocol click here.