by Mark Jenkins, M.D.

This feature is a continuation of the Performance Shop article on "Avoid the Crud" in the November 2002 issue of Runner Triathlete News. To get full details on exercise and the common cold, please read the Performance Shop article in that issue.

Nothing can be more frustrating for athletes than getting ill. As opposed to injuries, whether overuse or acute, illness seems to be completely unpredictable and unexpected. One minute you're fine and the next you're in bed with fever and chills. Upper respiratory tract infections (URIs) can really put a crimp in training and are especially frustrating if they strike just before a big race.

Here are some answers to some common questions regarding exercising with the common cold.

Q: What about Echinacea, vitamin C, or zinc? Do any of these help the common cold?
A: No. Personal anecdotes aside, the consensus from valid, controlled data does not support the use of these substances for the treatment, or prevention of URIs.

Q: Okay, but is there anything wrong with trying the herbal or homeopathic treatment of colds?
A: Scientific evidence lacking, many people do feel better using a certain regimen. In the absence of any high-technology medical cures for the common cold, patients are encouraged to do what makes them feel better. In many cases there are specific foods or substances that are beneficial or helpful for symptom relief and there is absolutely nothing wrong with utilizing them. For example, spicy foods can have an expectorant/decongestant effect. The bottom line is, if it seems to help and it is not too extreme - or toxic - then go for it.

Q: Is exercise an immune booster?
A: Yes. There is evidence that regular exercise results in a "training effect" on the immune system. In other words with a gradual progression, even those with very vigorous routines are healthier than their couch potato counterparts. This relative difference is greater the older one gets. So stay an athlete all your life. On the other hand doing relatively too much can temporarily lower immune function and make one more susceptible to URIs. The key word here is, "relative." Another recommendation to help your immune system, and other body systems, function better is to consume five servings of fresh fruits/vegetables per day.

Q: What about training though a cold?
A: The best advice is to rest during the initial stages of the illness and then resume an abbreviated training routine as you recover. For an average URI this usually means a few days off and then several more of reduced training. Recognize that more severe or prolonged symptoms dictate more time off. It is important not to workout with a fever because you will likely prolong the illness - resulting in even more time off training. Additionally, vigorous exercise during times of high viral load may predispose one to more severe complications of URIs (e.g., myocarditis). Thankfully, serious consequences are not common but a break from training is still the smart thing to do.

For more info check out the Centers for Disease Control's website at www.cdc.gov.

Dr. Jenkins is a team physician for Rice University and a 10- year triathlon veteran, including seven Ironman finishes. He treats a variety of collegiate, professional, and recreational athletes.