5 Does Exercise Help or Harm a Cold? Most people suffer from one to six colds per year, and people are able to fight them off whether they exercise or not. Exercise and physical activity enthusiasts and athletes often wonder whether working out has any effect on the severity or duration of cold symptoms. Recent research published by the American College of Sports Medicine (ACSM), in a recent issue of Medicine and Science in Sports & Exercise, indicates that moderate exercise during a rhinovirus-caused cold does not appear to make symptoms more severe or make them last longer.
Although it is known that moderate exercise may decrease the risk of acquiring an upper- respiratory infection, nothing had previously been documented to demonstrate whether training while suffering from a cold would reduce or intensify the symptoms. Fifty moderately-fit student volunteers were recruited for the study, and divided randomly between two groups: exercising and non-exercising.
The exercise group trained at 70 percent of their measured heart rate reserve for 40 minutes at the same time every day, either running, stair climbing or bicycling. Each student participant was inoculated with a predetermined number of infectious particles of a rhinovirus and then all exercisers and nonexercisers were followed for a 10-day period. All participants were asked to refrain from self-treating their colds. At the study’s conclusion, no statistically significant difference was evident between the exercising and non-exercising groups.
The authors conclude that exercise at this level apparently does not intensify cold symptoms. A possible reason for that is that the intensity of exercise the students used was not enough to alter immune responses. Highintensity exercise has been shown in the past to have a negative effect on immune function during an upper-respiratory-infection (URI). The authors cite a useful model for exer- cising with a cold. If symptoms such as a runny nose, sneezing or a scratchy throat exist (so-called “above-the-neck” symptoms), it is probably safe for an individual to exercise at a lower intensity.
If these symptoms go away during the first few minutes of exercise, the exercise intensity may be increased. Exercise is not, however, recommended for individuals experiencing “below-the-neck” symptoms of a cold, such as fever, sore muscles or joints, vomiting or diarrhea, or a productive cough. People with such symptoms are urged to allow the illness to run its course and resume physical activity when the cold is gone. The results of this study conclude that “above-the-neck” symptom sufferers will not experience an illness that is longer than normal or has worse symptoms if they do moderate-intensity exercise.
This was the first study that specifically examined the influence of exercise training on a rhinovirus-caused upper-respiratoryinfection. Rhinoviruses are thought to be responsible for only 40 percent of annual colds; so other types of virus cause the majority of these illnesses. It remains to be seen whether similar results can be observed for colds induced by those other types, or whether the colds they produce respond differently to exercise.