Newswise — Exercise is the best protection against catching a cold, according to research conducted by Appalachian State University's David Nieman. Nieman is a professor in Appalachian's Department of Health, Leisure and Exercise Science and director of the university's Human Performance Lab.
For more than 10 years, Nieman has studied the relationship between exercise, the immune system and upper respiratory tract infection. His findings show that near daily exercise boosts the immune system and reduces sickness.
"People who walk at a brisk pace for 40 or 45 minutes on a nearly daily basis have half the sick days with the common cold than people who don't walk at all," Nieman said.
Regular exercise releases more "killer cells" and antibodies into the body, Nieman explained. These natural immune cells circulate throughout the body "patrolling" for germs, such as the cold virus. However, too much exercise -- such as an hour-and-a-half- long run or bike ride -- can weaken the immune system's ability to fight illness.