A Brisk Walk A Day May Keep Colds Away

There may be a new reason to exercise: Doing so may keep those sniffles and sneezes away.

As The Early Show medical correspondent Dr. Emily Senay reported Monday, a new study suggests that regular, moderate exercise might help prevent the common cold.

The study at the Fred Hutchinson Cancer Research Center in Seattle followed 115 sedentary, overweight, postmenopausal women for a year, Dr. Senay explained. Half did moderate exercise for an average of 30 minutes per day. The exercise of choice was generally walking, either outdoors or on a treadmill. The other half limited physical activity to 45 minutes of stretching, once a week.

The study was primarily set up to examine broader health issues that affect older women, including cancer, but one finding that caught the eye of researchers was how frequently these women caught colds.

The women whose exercise was limited to weekly stretching reported catching nearly twice as many colds during that year as the women who spent a half-hour walking every day. The study participants didn't change their diets, or other aspects of their lifestyles. The only thing that seemed to change was the amount of exercise they got. So, the researchers suggest that exercise is what made the difference.

The longer the study lasted, the wider the gap between the two groups of women became, Dr. Senay said. In months 9 through 12, the group that only stretched reported three times as many colds as the group that really exercised. That seems to suggest that the benefits of regular exercise increased with time.

The study wasn't designed specifically to find out whether it was the exercise that made the difference, Dr. Senay said. But previous research has found a correlation between walking and temporary increases in levels of white blood cells, which are an essential component of the immune system. A co-author of this new study says her results appear to be consistent with that. Also, since those other studies involved a broader slice of the population, there's reason to believe that regular exercise might also improve immunity against colds in younger women and in men, as well.

Daily aerobic activity that raises the heart rate, which includes taking brisk walks, can help reduce high blood pressure, Senay added. It also can improve a person's cholesterol levels. Research suggests that people who exercise regularly might reduce their risk of diabetes, and accomplish something that helps both their health and their appearance: losing weight.

And if the results of this study are confirmed, and people who exercise really do get fewer colds, that would be yet another benefit of exercising.