Background: Prostate cancer is a disease of older age, and there is significant overlap with age-related illnesses. Androgens play a critical role in prostate cancer but also have been linked to cardiovascular (CV) disease, metabolic syndrome, bone health, and frailty. ADT is associated with an increased risk of CV events primarily due to increased rates of diabetes, dyslipidemia, and adverse changes in body composition. We assume that prostate cancer and age-related illnesses share biology with therapeutic implications in a subset of men. The ProTrio trial will test the hypothesis that a 16-week digital risk factor modification program will improve 10-year atherosclerotic cardiovascular disease (ASCVD) risk score as compared to usual care in men with potentially lethal prostate cancer receiving ADT. Methods: This single center, open-label, randomized phase II trial is evaluating a 16-week digital risk factor modification program, which includes an exercise prescription (150 minutes of titrated cardiovascular exercise and resistance exercise 2 times a week) with support via a smart phone application (Moving Analytics) and Fitbit, in patients with prostate cancer who are receiving ADT compared to usual care with Fitbit monitoring. Eligible patients are men receiving ADT +/- an androgen signaling inhibitor for at least 3 months prior to enrollment. The study will enroll to two cohorts: (1) distant metastatic disease and (2) biochemically recurrent or regional lymph node disease. Patients will be stratified according to their baseline ASCVD risk score. The primary endpoint is the difference in ASCVD risk score post-intervention. Secondary endpoints include difference in metabolic severity index z-score, PSA velocity, 6-minute walk, 5X Sit-to-Stand, body composition, physical activity measured by Fitbit, and health-related quality of life. Up to 100 patients will be enrolled in each cohort. A clinically relevant improvement in ASCVD score reduction is 2.5%. With 44 men per arm, after 12% dropout, we can detect an improvement of 2.5% vs. 0% at a 2-sided 5% significance level with 80% power assuming a standard deviation (SD) of 4.125%. A sample size adjustment is planned based on the SD of the first cohort to reach 44 patients. Each cohort will undergo futility analysis once half the men are enrolled. The study is enrolling at MD Anderson Cancer Center. Clinical trial information: NCT05054296.