Testosterone undecanoate (17β-hydroxyandrost-4-en-3-one undecanoate) is a very long-acting ester of testosterone formulated for extended hormone release and minimal injection frequency. It supports anabolic activity by increasing nitrogen retention, stimulating protein synthesis, and enhancing red blood cell production—key factors in muscle growth, strength, and improved recovery. Due to its prolonged half-life and stable pharmacokinetics, testosterone undecanoate provides a consistent hormonal environment, making it ideal for both long-term therapeutic use and sustained performance enhancement.