How does exercise affect my immune system?

Researchers at the University of Washington showed that regular, moderate intensity exercise (like brisk walking) helps improve your resistance to the common cold. In their study, 115 sedentary and overweight women were assigned to do either 45 minutes of moderate intensity exercise or 45 minutes of stretching 5 days weekly for one year. Before starting the study, women in both groups reported having the same number of colds. On average, women exercised about three and one-half days per week during the year of the study. Over the year, women doing moderate exercise experienced a modestly decreased risk of having a cold, while colds increased slightly in those doing only stretching. During the final three months of the study, the risk of colds was over three times higher among women doing just stretching compared with those doing daily aerobic exercise. So get exercising and give your tissue box a rest!

Exercise will boost your immune system.  Being active helps your body to stay active.  When your body is alert and energized, it will be able to stay strong and fight off unwanted germs and bacteria which will help prevent getting sickness such as your common cold.