Physiological changes in the body during a workout include increased heart rate, enhanced blood flow, and the release of various hormones. As the body engages in physical activity, the heart pumps more effectively to deliver oxygen and nutrients to working muscles. During this process, endorphins and adrenaline are released, contributing to improved mood and reduced perceived exertion. Additionally, muscles experience micro-tears, leading to repair and growth during recovery. These physiological adaptations enhance overall fitness, strength, and endurance over time.