Moderate Exercise May Protect Against Colds
A moderate exercise program may reduce the incidence of colds. A study published in the November issue of The American Journal of Medicine, led by researchers at Fred Hutchinson Cancer Research Center, found that otherwise sedentary women who engaged in moderate exercise had fewer colds over a one year period than a control group.
Subjects in a group of 115 overweight and obese, sedentary, postmenopausal women were randomly assigned to either a moderate exercise program (45 minutes per day, five days per week and comprised of mostly brisk walking) or to a once-weekly 45 minute stretching session. Both the exercisers and the stretchers filled out questionnaires every 3 months on the number of episodes of allergies, upper respiratory tract infections (colds and flu) and other infections. Subjects were taught how to distinguish various forms of infections and were followed for one year.
Over 12 months, the risk of colds decreased modestly in exercisers and increased modestly in stretchers. In the final three months of the study, the risk of colds in stretchers was more than 3-fold higher than that of exercisers. More stretchers than exercisers had at least one cold during the 12-month study period (48.4% vs 30.2%), and among women reporting at least one cold, stretchers tended to report colds more frequently than exercisers.
Senior author Cornelia M. Ulrich, PhD, of the Hutchinson Center, writes, "Our trial is the first to report on the effects of a year-long, moderate-intensity exercise training program on the incidence of upper respiratory tract infections. Although we did not find an effect overall on upper respiratory tract infections, our study suggests that moderate-intensity training can reduce the risk of colds in postmenopausal, nonsmoking, overweight or obese women. This finding is of clinical relevance and adds a new facet to the growing literature on the health benefits of moderate exercise."