The primary hormone released during resistance training is testosterone. Testosterone plays a significant role in promoting muscle growth, strength, and recovery. During resistance training, especially high-intensity workouts, the body releases testosterone in response to the physical stress placed on muscles. This hormone aids in protein synthesis, which is crucial for muscle repair and growth post-exercise. Additionally, testosterone contributes to increasing muscle mass, enhancing overall physical performance, and improving metabolic health. Adequate levels of testosterone are important for optimal fitness progress and effectiveness of strength training regimens.