a jog around the block a few times a week not only can do wonders for your physique -- it also might prevent you from getting sick. “i try to get 20 to 30 minutes of cardio every morning before i go to work ” sandra fryhofer md says. “there’s something about making your heart pump that’s good for your body. it strengthens your heart and strengthens your immune system. ” the research seems to agree -- one study found that postmenopausal women who exercised for a year had one-third the colds of women who didn’t work out.
does exercise really boost immunity?