Exercising with Colds and Flu
By Scott Sarran, M.D.
Lutheran General Fitness Center

Many exercising adults come to me with questions about exercise and its relationship to colds and flu. These questions tend to fall into one or two categories:

1. What is the effect of exercise on their chances of catching colds or the flu
2. What are the guidelines for the modification of exercise during an episode of illness.

In general, the answer to the first question is the old story of how many things in moderation are healthy, but few things taken to excess are without risks. People whose lifestyle is healthy overall, with a good diet, sufficient rest and a regular exercise program tend to have well-functioning immune systems and seem to have less infections (and recover quicker) than the average person.

On the other hand, people who are pushing their bodies to the limits of their endurance are at higher risk for developing a variety of illnesses. An example of the latter phenomenon is the well-documented increase of respiratory infections in the marathon runner, peaking during times of maximal training mileage and during the immediate post-marathon period.

The best answer to the second question is to cut down on the intensity and duration of exercise during a mild episode of infection, and to rest altogether in the presence of a fever. When the body is fighting a germ, there is definitely less stamina for exercise. In the presence of a fever, the heart rate and respiratory effort are already significantly increased, dehydration is more likely, and is not wise to further stress the body with exercise.

In addition, people over the age of 65, people with a history of diseases of the cardiac, respiratory (such as asthma), endocrine or immune system, and people exposed to numerous potential sources of disease, are candidates for the flu shot and the pneumonia vaccine. The pneumonia vaccine needs to be given only once in a lifetime. The flu shot and pneumonia vaccine are available in November or December.