What are some short-term benefits of physical activity on the body?

The benefits of physical activity on the body can be observed almost immediately, and faster metabolism and improved sleep stand out as significant short-term advantages. When individuals engage in physical activity, their metabolic rate tends to increase, leading to more efficient calorie burning and energy utilization. This increase in metabolism is often a direct result of the body's efforts to support heightened physical exertion.

Additionally, exercise has a profound impact on sleep quality. Regular physical activity can help individuals fall asleep faster and enjoy deeper sleep cycles. This is attributed to the way exercise influences the body's circadian rhythm and the production of sleep-related hormones such as melatonin. Improved sleep not only contributes to better recovery but also enhances overall well-being, mood, and cognitive function.

The other options do not align with the recognized short-term benefits of physical activity. For instance, improved immune response and appetite are typically longer-term effects rather than immediate changes. Decreased heart rate usually occurs as a result of regular exercise rather than immediately following it, and muscle atrophy is counterproductive to the goals of physical activity, which is to strengthen muscles. Furthermore, loss of flexibility and decreased stamina would not be considered benefits of physical activity; in fact, exercise generally promotes flexibility and enhances stamina over time.