What are the physiological and psychological benefits of regular physical exercise, and how does exercise contribute to overall health and well-being?

Regular physical exercise has numerous health benefits, including improved cardiovascular fitness, muscle strength, flexibility, and endurance. It reduces the risk of chronic diseases such as obesity, diabetes, hypertension, and depression, enhances mood, cognitive function, and sleep quality, and promotes longevity and quality of life. Exercise also stimulates the release of endorphins, dopamine, and serotonin, neurotransmitters that promote feelings of happiness, relaxation, and stress relief.