|Working Out When to Exercise in the Cold and Flu Season|
Sniffles, runny noses and flu-like symptoms can deter, delay and even derail many exercisers just when enthusiasm for that New Year's resolution is beginning to flag.
Health and fitness experts advise to starve a fever of exercise. But feeding a cold moderately, with a brisk walk, may not be a bad idea.
"The classic line from every sports medicine doctor is, ‘If you can do it, do it. If you can't, don't,'” said Dr. Lewis G. Maharam, author of "Running Doc's Guide to Healthy Running."
Usually if symptoms are confined to above the neck, exercising is OK, he explained. But if you're running a fever of 101 degrees Fahrenheit (38.3 degrees Celsius) or higher, skip it.
Body heat rises during exercise due to increased metabolism, explained Maharam, who practices medicine in New York City. If you start high, your body's way of cooling you down is out of balance.
"If fever gets too high, you break down proteins, maybe in the kidneys or liver," he said.
The U.S. Centers for Disease Control and Prevention estimates that more than 425 million case of colds and flu occur annually in the United States. The average person has about three respiratory infections per year.
Dr. David C. Nieman, a professor of health sciences at Appalachian State University, North Carolina Research Campus, said research shows that regular, moderate aerobic exercise strengthens the immune system, and that people who exercise report fewer colds than their inactive peers.
Nieman said five days or more of aerobic activity per week was found to be a powerful factor in lowering the number of sick days.
"Even three to four days was effective. To be avoided was being sedentary," he explained.
But when animals infected with a systemic virus are forced to exercise in fever and pain, studies show that their symptoms are exacerbated, prolonged, and sometimes life-threatening.