It’s a question that has dazzled us for hundreds of years. Should you or should you not work out when you are sick? When is it ok to pick up the training shoes again? There is a very simple but also very effective rule of thumb for exercising when sick, and we’re going to take a closer look at it.

Did you know that the average adult has two to three upper respiratory infections each year? Thomas G. Weidner, Ph.D., director of athletic training programs at Ball State University in Muncie, Ind., tracked 22 men and women, ages 18-29, who had just begun to exercise in the previous three months and had caught colds.

Weidner had half the participants work out at a moderate 70 percent of their target heart rate for 30 minutes five days a week using an indoor bike, treadmill or stair-climbing machine; the other half did no exercise, and no one took cold medicine. After a week, he found no difference in symptoms between the two groups. “It’s OK for moderate exercisers and people who have just begun a workout program to exercise with a head cold,” Weidner says. “The severity and duration of a cold don’t seem to be altered by exercise.”

The general rule of thumb you should keep in mind the next time you pick up a cold goes like this: If your symptoms are above the neck, including a sore throat, nasal congestion, sneezing, and tearing eyes, then it’™s OK to exercise. On the other hand if your symptoms are below the neck, such as coughing, body aches, fever, and fatigue, then it’s time to hang up the running shoes until these symptoms subside.

It is also worth mentioning that most experts agree on one thing. If there are symptoms or signs of the flu, such as fever, extreme tiredness, muscle aches, swollen lymph glands, then at least two weeks should probably be allowed before you resume intensive training. Intensive training is the keyword here. You can start you training at a earlier stage, but don’t overload yourself with 100% right away.

Here are a few tricks and tips how you can reduce the chances of picking up a cold (source: About.com)

• Eat a well-balanced diet. The immune system depends on many vitamins and minerals for optimal function. However, at this time, there is no good data to support supplementation beyond 100 percent of the Recommended Dietary Allowances. A good rule is to eat 10-15 calories per pound of “desired body weight.” If your ideal weight is 170 lbs, then consume 1700-2550 calories a day (1700 for sedentary individuals and 2550 for extremely active types.)
• Avoid rapid weight loss. Low-calorie diets, long-term fasting and rapid weight loss have been shown to impair immune function. Losing weight while training heavily is not good for the immune system.
• Obtain adequate sleep. Major sleep disruption (e.g., three hours less than normal) has been linked to immune suppression.
• Avoid over-training and chronic fatigue. Space vigorous workouts and race events as far apart as possible. Keep “within yourself” and don’t push beyond your ability to recover.
• Wash your hands frequently. This is often your best prevention. Don’t forget your fingernails.
• Avoid putting your hands near your eyes, nose or mouth. Most bacteria and germs are spread from a surface to your hands to your face not by air.
• Get a flu shot. Especially if you have a weakened immune system.
• Get enough sleep. Lack of sleep can reduce immune functioning making you susceptible to sickness.
• Drink more water. In the fall and winter, it is easy to overlook your thirst and get dehydrated. Make sure you consume 8 glasses a day.
• Continue a moderate exercise program. Try to maintain a consistent exercise routine
• Limit alcohol intake. Alcohol can be dehydrating which, in turn, may decrease your resistance to bacteria.
• Finally, listen to your body. If you are less than 100% you will feel better and recover faster if you let yourself rest.

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