The body adapts to varying levels of physical activity through a process known as physiological adaptation. When individuals engage in regular exercise, their muscles, cardiovascular system, and metabolism become more efficient. This results in improved strength, endurance, and flexibility over time. Additionally, the body develops greater tolerance to physical stresses, reducing the risk of injuries. These adaptations enable individuals to handle increased workout intensity or volume. However, adjusting exercise programs is essential to continue challenging the body and promoting ongoing adaptations.