Table 1 Key Eligibility Criteria

1. Subject age ≥ 18 years old

2. Metastatic castration-sensitive prostate cancer patients who have not met standard criteria for disease progression on current systemic therapy

3. Currently treated with surgical castration or medical castration with GnRH agonists/antagonists, and/or an androgen receptor pathway inhibitor (e.g., abiraterone, enzalutamide, apalutamide, darolutamide) ^*

4. ECOG Performance Status ≤ 2

5. Not currently adhering to national physical activity guidelines for resistance training, as defined as participating in structured resistance training ≥ two days per week.

6. Regular access to an electronic device with internet service and ability for video calls

7. Access to an active MyChart account or the willingness to create an account for the purposes of the trial

8. Willingness to engage in a home-based resistance exercise program two days per week

9. Willingness to take creatine monohydrate supplementation or placebo for the duration of the 52-week trial and to avoid taking additional creatine-containing supplementation or other nutritional supplementation during the study period

10. Willingness to complete and submit weekly supplementation logs to study personnel throughout the duration of the 52-week study via email, text, in person, or verbally verified over the phone

11. Willingness to complete three in-person assessment sessions (baseline, 24-, and 52-weeks)

12. Able to provide informed consent and willing to sign an approved consent form that conforms to federal and institutional guidelines

Exclusion Criteria

1. Treatment with cytotoxic chemotherapy within 12 weeks prior to enrollment

2. eGFR < 30 ml/min/1.73m²