Another reason to fit exercise into your day: Having a regular workout could mean catching fewer colds. Research shows that after exercise, your body produces more antibodies that attack foreign invaders like bacteria or viruses. A few hours after you complete your exercise routine, your body returns to normal. However, it appears that the more often you exercise, the longer those antibodies circulate in your system.
David Nieman, DrPH, of Appalachian State University in Boone, North Carolina, says his studies have found that subjects who walked with some moderate intensity for 40 minutes a day had half as many sick days from colds and sore throats than those who didn't exercise.
