During exercise, the body undergoes several physiological responses to meet increased demands for energy and oxygen. The heart rate increases to pump more blood, delivering oxygen and nutrients to muscles. Additionally, breathing rate rises to enhance oxygen intake and carbon dioxide removal, supporting sustained physical activity. Muscles also experience changes, such as increased blood flow and temperature, which help improve performance and reduce the risk of injury. Hormones like adrenaline are released, boosting energy availability and enhancing endurance. These adaptations are essential for maintaining physical activity and overall health during exercise.