Abstract Body: Physical activity, a key component of Life’s Essential 8, is critical for cardiovascular health, especially among older Latinx adults—a demographic with a high prevalence of at least one cardiovascular disease (CVD) risk factor. Despite previous interventions aimed at helping older adults meet age-specific physical activity (PA) guidelines, achieving this objective continues to be a challenge. This study utilized signal detection analysis (SDA) to identify combinations of baseline demographic, clinical, behavioral, and psychosocial factors, alongside intervention type, that predicted meeting the ≥ 150 minutes per week walking goal at the 12-month study endpoint among insufficiently active older Latinx adults enrolled in COMPASS (Computerized Physical Activity Support for Seniors) – a cluster-randomized physical activity (PA) effectiveness trial. From July 2014 to July 2016, a total of 245 participants aged 50 and older from the San Francisco Bay Area were randomly assigned to either a human peer advisor or a virtual advisor intervention arm. The PA goal was assessed using the validated Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire. SDA, a recursive partitioning exploratory method, was used to explore subgroups of participants most and least likely to achieve the goal of ≥150 minutes of walking per week, based on the intervention arm and other predictors. Overall, 49.8% of participants met the walking goal. Among those living in smaller households (<3 people), higher acculturation to US media (score of 5) and lower resting systolic blood pressure (<117 mmHg) were the strongest predictors of success. For participants in larger households (≥3 people), fewer hours of sedentary behavior (<33.8 hr/week) and lower resting heart rate (<64 bpm) were key predictors of success. Notably, the intervention arm was not a significant factor in achieving the PA goal. Study findings underscore the need to focus on specific subgroups to optimize PA interventions. Combinations of factors such as acculturation, cardiovascular health markers, and sedentary behavior may play a critical role in achieving PA outcomes among older Latinx adults. These findings support a precision exercise approach to PA interventions that target the unique needs of aging, underactive minority populations.