Community interventions boost physical activity in low- and middle-income countries

Of the 24 studies reviewed, 16 (67%) reported significant improvements in physical activity outcomes. The magnitude of change varied: metabolic equivalents increased by 100–2,700 units, moderate-to-vigorous physical activity rose by 7–60 minutes per week, and daily step counts increased by around 3,000 steps. Digital and technology-based interventions (n=10) showed the most consistent significant improvements, followed by peer-led or community health worker-facilitated programs (n=8) and environmental restructuring approaches (n=6). Notably, only two studies directly measured sedentary behavior as a primary outcome, suggesting this outcome remains underexplored. Shorter interventions (6 months or less) and medium-duration programs (6–12 months) were more likely to report significant improvements than longer programs exceeding 12 months, a pattern the authors note as counterintuitive and highlighting the need for more rigorous evaluation of sustained interventions.

The review found that digital interventions demonstrated more consistent positive effects than other delivery methods—a notable finding given the expanding mobile phone penetration in LMICs. The data on sedentary behavior was sparse (only 2 of 24 studies made it a primary focus), meaning the evidence for sitting-time reduction remains limited. Interestingly, the proportion of studies showing significant effects was similar whether interventions focused narrowly on physical activity and sedentary behavior (89%) or took a broader lifestyle approach (53%), suggesting focused programs may have an edge. The counterintuitive finding that longer interventions (>12 months) reported fewer significant improvements than shorter ones may reflect implementation drift, publication bias (negative long-term trials less likely to be published), or real decline in adherence over time—the authors emphasize this as a key gap requiring better-designed long-term studies. Effect sizes ranged widely (100–2,700 METs, 7–60 min/week MVPA), indicating heterogeneous interventions and populations; comparison to high-income country studies would help contextualize these magnitudes.