Regular exercise can significantly boost your immune system in several ways. Firstly, physical activity can help to flush bacteria out of the lungs and airways, reducing the chance of getting a cold, flu, or other illness. Additionally, exercise causes changes in antibodies and white blood cells, which are the body's immune system cells that fight disease. These cells circulate more rapidly, so they could detect illnesses earlier than they might have before.

Furthermore, exercise can contribute to overall good health, which can help to support your immune system. For example, regular moderate-intensity exercise can reduce inflammation and help your immune cells regenerate regularly. Moreover, exercise can also help to reduce stress and its negative impact on the immune system.

Several studies have supported the positive effects of exercise on the immune system. For instance, a study published in the American Journal of Medicine found that regular, moderate-intensity exercise can reduce the risk of respiratory infections. Another study in the British Journal of Sports Medicine showed that regular physical activity can enhance the immune response to vaccination.