Objectives: This within-participants, single time-series study tested a train-the-trainer, promotor-based physical activity (PA) intervention to improve fitness and health indicators.
Methods: Thirty unpaid promotores were trained to promote PA through free exercise classes. Measurements of 337 female community participants at baseline, 6 months, and 12 months assessed changes in health indicators, including systolic and diastolic blood pressure, waist circumference, body mass index (defined as weight in kilograms divided by the square of height in meters), aerobic fitness, and hamstring flexibility, as well as self-reported health indicators (PA, depression) and psychosocial factors (barriers, self-efficacy, and social support-all specific to PA).
Results: Mixed effects models showed intervention participation improved systolic blood pressure (P ≤ .001), waist circumference (P ≤ .001), fitness (P ≤ .001), and hamstring flexibility (P ≤ .001). We also noted improvements in use of community resources (P ≤ .05), depressed mood and anhedonia (P ≤ .01), perceived barriers to be physically active (P ≤ .05), and community support for PA (P ≤ .001). Self-efficacy decreased (P ≤ .05), and participation dose (i.e., exposure), as measured by attendance at exercise classes, was not associated with observed changes.
Conclusions: Promotores can promote PA in their community and achieve meaningful changes in the residents' health.