A theory-driven exercise intervention to improve physical performance in community-dwelling older adults: a cluster randomized controlled trial delivered by general practitioners

Age-related physical decline demands effective community-based interventions. Theory-driven programs, especially those led by general practitioners (GPs) and integrating behavior change techniques (BCTs), remain underexplored. This cluster randomized controlled trial aimed to evaluate the effectiveness of a GP-delivered, group-based exercise intervention-designed based on the Theory of Planned Behavior (TPB) and operationalized with BCTs-on improving moderate-to-vigorous physical activity (MVPA) and physical performance among community-dwelling older adults. A total of 429 older adults from 36 communities were randomized to either the intervention or control group. The randomization was performed at the community level. The primary outcome was MVPA, the secondary outcomes were timed up-and-go test time (TUG), Berg Balance Scale score (BBS), light intensity physical activity (LPA), falls efficacy, and loneliness. The intervention group participated in four weekly 60-minute group sessions that incorporated BCTs mapped to the TPB constructs, such as “modelling or demonstrating the behavior”, “social comparison”, “goal setting”, “behavioral contract”, etc. The control group received two monthly 60-minute group lectures designed to provide general health education on the knowledge of physical activity. Data were collected at baseline, 4 weeks (post-intervention) and 12 weeks. Adjusted difference was relied on linear mixed models. After 4 and 12 weeks, the intervention group demonstrated significant increases in MVPA compared to the control group, with a mean difference of 1.77 h/week (95% CI: 1.45, 2.10) and 1.96 h/week (95% CI: 1.64, 2.28), respectively. Significant improvements were also observed in BBS, TUG, and fall efficacy at 12 weeks. No significant between-group differences were found for LPA and loneliness. The program could be suggested as an efficient intervention for improving physical performance and fall efficacy in community older adults due to the increase in PA. International Traditional Medicine Clinical Trial Registry (ITMCTR2025002002). Retrospectively registered, with the registration dated 22/10/2025.