Exercise influences energy levels throughout the day by enhancing circulation and improving cardiovascular health, which boosts overall stamina and reduces feelings of fatigue. Regular physical activity stimulates the release of endorphins, leading to increased motivation and alertness. Engaging in short bouts of exercise, such as walking or stretching, can provide an instant energy boost by combating feelings of lethargy. Over time, people who exercise regularly often experience improved sleep quality, resulting in higher energy levels during the day.