The findings are based on a small study and need to be confirmed. "But if our results turn out to be true... that's monumental," said Dr. Bruce Barrett of the University of Wisconsin-Madison, who led the work.
"The only preventive things that we have at our disposal right now (for colds) are hand washing and avoiding sick contacts," Barrett told Reuters Health.
Previous work has suggested that people who exercise or have low stress levels are less likely to get sick. To test whether exercise and positive thinking could actually prevent illnesses, Barrett and his colleagues studied 149 people randomly assigned to one of three groups.
One group participated in an eight-week meditation program, another did an eight-week exercise program, and the last group received no special instruction.
The training groups had two-and-half hour weekly group sessions along with another five days each week of practicing on their own for 45 minutes.
The exercise group did aerobics, cycling, jogging or brisk walking. The meditation group worked on mindfulness, a form of meditation emphasizing awareness of stress reactions and sources of stress.
After the weeks of training, the researchers surveyed the participants throughout a flu season to track how many people got sick.
Among the people in the meditation group there were 27 bouts of respiratory illness throughout the study, compared with 26 cases in the exercise group and 40 in the passive comparison group.
Those who meditated reported less-severe symptoms overall. And people spent only five days on average feeling sick if they worked out or meditated, compared to nine days in the comparison group.
"I suspect this is because they are better able to cope with the symptoms," said James Carmody, a mindfulness researcher at the University of Massachusetts Medical School in Worcester, who was not involved in the study.
He said that when people are sick, they tend to dwell on how unpleasant their symptoms are.
"Keeping attention focused on the thoughts is going to add to the unpleasantness," he told Reuters Health. With mindfulness, "people learn to redirect their attention so they don't stay stuck on unpleasant thoughts."
The exercise and meditation groups also missed work less often during the study. The exercise group had 32 sick days due to colds and similar infections and the meditation group had 16, whereas the comparison had as many as 67.
"What this study did was it confirmed what other studies have shown, that regular activity reduces illness days and symptoms," said David Nieman, a professor of health, leisure and exercise science at Appalachian State University in Boone, North Carolina, who was not involved in the new research.
Nieman, who is a consultant to Barrett on grant proposals, has found in his own work that people who exercise most days of the week have a 40- to 45-percent reduction in sick days.
Nieman said that exercise stimulates the immune system to better patrol the body for any potential viral invaders.
"It helps the immune system do its job better," he told Reuters Health.
"No medication or supplement has produced preventive findings as strong as these," he said.
There is no vaccine to prevent the common cold, and no medicine that can cure it. Flu vaccines can prevent infections 60 to 70 percent of the time in healthy people, Barrett said.
He cautioned that because the study was the first of its kind, the findings are only preliminary and there still remains a "big if" as to whether exercise or meditation can prevent people from getting sick in the first place. Barrett and his colleagues are starting another trial with a larger group of people.
SOURCE: http://bit.ly/Mit5D4 Annals of Family Medicine, July 9, 2012