Don’t Starve a Cold of Exercise
By GINA KOLATA
Published: December 24, 2008
YOU have what seems to be a really bad cold. You are coughing and sneezing, and it is hard to breathe.
Should you work out?
And if you do, should you push yourself as hard as ever or take it easy? Will exercise have no effect, or make you feel better or worse?
It is a question, surprisingly enough, that stumps many exercise physiologists and infectious disease specialists.
“That question has not been actually studied,” said Dr. Aaron E. Glatt, a spokesman for the Infectious Diseases Society and the president of New Island Hospital in Bethpage, N.Y.
Many avid exercisers make up their own rules, and it seems that many of them, like Dr. Michael Joyner, an exercise researcher at the Mayo Clinic who is a swimmer and runner, decide to keep exercising if they possibly can.
“I can tell you that unless I am really wiped out, I still work out but maybe scale back a bit,” Dr. Joyner said. “I think that would be the answer from most relatively hard-core, old-school types.
“If I have an obvious fever and muscle aches,” he continued, “I do very little or take a day or two off, but I really have to be in a bad way to skip more than that.”
Dr. Bill Schaffner, chairman of the department of preventive medicine at Vanderbilt University and a member of the board of directors of the Infectious Diseases Society, said he was unaware of any studies that addressed the issue.
Dr. Schaffner described himself as a jogger who runs a few miles most days and goes to a gym for resistance training. And, he said, he continues his workouts when he has a cold.
Exercise, he said, makes him feel better. He speculates that perhaps it is because his blood vessels are dilated when he exercises.
“I think exercise pushes me along a route to recovery,” Dr. Schaffner said. “Of course, I recognize that I might have been on a route to recovery anyway. But I can’t think of a reason why exercise would affect you adversely.”
It turns out that, even though they were unaware of them, the strategies of people like Dr. Schaffner and Dr. Joyner are actually supported by two little-known studies that were published a decade ago in the journal Medicine & Science in Sports & Exercise. Results from the studies were so much in favor of exercise that the researchers themselves were surprised.
The studies began, said Leonard Kaminsky, an exercise physiologist at Ball State University, when a trainer at the university, Thomas Weidner, wondered what he should tell athletes when they got colds.
The first question was: Does a cold affect your ability to exercise? To address that, the researchers recruited 24 men and 21 women ages 18 to 29 and of varying levels of fitness who agreed to be deliberately infected with a rhinovirus, which is responsible for about a third of all colds. Another group of 10 young men and women served as controls; they were not infected.
At the start of the study, the investigators tested all of the subjects, assessing their lung functions and exercise capacity. Then a cold virus was dropped into the noses of 45 of the subjects, and all caught head colds. Two days later, when their cold symptoms were at their worst, the subjects exercised by running on treadmills at moderate and intense levels. The researchers reported that having a cold had no effect on either lung function or exercise capacity.
“I was surprised their lung function wasn’t impaired,” Dr. Kaminsky said. “I was surprised their overall exercise performance wasn’t impaired, even though they were reporting feeling fatigued.”
He said he also tested the subjects at different points in the exercise sessions, from moderate to intense effort, and found that their colds had no effect on their metabolic responses.
Another question was: Does exercising when you have a cold affect your symptoms and recovery time?
Once again, Dr, Kaminsky and his colleagues infected volunteers with a rhinovirus. This time, the subjects were 34 young men and women who were randomly assigned to a group that would exercise with their colds and 16 others who were assigned to rest.
The group that exercised ran on treadmills for 40 minutes every other day at moderate levels of 70 percent of their maximum heart rates.
Every 12 hours, all the subjects in the study completed questionnaires about their symptoms and physical activity. The researchers collected the subjects’ used facial tissues, weighing them to assess their cold symptoms.
The investigators found no difference in symptoms between the group that exercised and the one that rested. And there was no difference in the time it took to recover from the colds. But when the exercisers assessed their symptoms, Dr. Kaminsky said, “people said they felt O.K. and, in some cases, they actually felt better.”
Now, Dr. Kaminsky said, he and others at Ball State encourage people to exercise when they have colds, at least if they have the type producing symptoms like runny noses and sneezing. He is more cautious about other types of colds that produce fevers or symptoms below the neck such as chest congestion. Exercising with a head cold is not an issue for athletes, Dr. Kaminsky said, because most of them want to train no matter what. “If anything they tend to push too much,” he said.
Dr. Kaminsky also runs a fitness program at the university, dealing with regular exercisers. When he tells them it is all right to exercise when they have a cold, many are “a little suspicious,” he said. Often, they want to back off a little, lowering the intensity of their efforts.
“We tell them that’s O.K. if it’s for a short period of time,” Dr. Kaminsky said. “But what you have to be cautious of, where I see it as more of an issue, is with people who are trying to build that exercise habit. They’ve got all these barriers anyway.”
AND too often taking time off because of a cold is the start of falling away from the program entirely.
Dr. Kaminsky, who runs and works out on elliptical cross trainers and does resistance training, takes the studies’ findings to heart. Now when he has a cold, he continues to work out.
“It did give me the personal assurance that it was a good thing to do,” he said.