Exercise May Compound Cold Woes

Exercising with a cold is tough enough. Exercising with cold medications may make things even tougher.

Side effects of many over-the-counter and prescription drugs may add to the strength-sapping effects of the illness, doctors say. And, although the combination of exercise and drugs doesn’t create new side effects, it can make the standard ones more noticeable, they say.

For instance, common decongestants containing such substances as epinephrine can raise the resting heart rate, said Dr. Thomas L. Schwenk of the University of Michigan Medical School. And over-the-counter cold preparations almost always have antihistamines that can make some people feel drowsy, he said. One such compound is astemizole.

“They don’t balance each other out,” Schwenk said. “You can feel low motivation while your heart rate is up.”

The more hard driving the athlete, the more noticeable the effect could be, said Schwenk, who summarized some of the drug reactions in the medical journal the Physician and Sportsmedicine.

Competitive athletes are most likely to tell a difference in their performance, Schwenk said. Serious noncompetitive athletes probably would notice it, but recreational athletes might just think, “I’m not feeling well,” he said.

And the effect also varies from person to person, whether or not they exercise, said Dr. Gary I. Wadler of New York University. Some people “get really shaky and get insomnia,” he said. “Others will take [a drug] and have no effects except their nose stops running.”

The only way to know is to try some and see what happens, Wadler said. To avoid having your experiment hurt performance, try it when you are not planning to exercise, he said.

Athletes who get prescription medication after seeing a doctor may also have similar problems, said Dr. Douglas B. McKeag of the University of Pittsburgh. Many prescription drugs have side effects similar to the less powerful over-the-counter products, he said. For instance, prescription decongestants may speed up the resting heart rate, he said.

For an aerobic athlete, that’s bad news, McKeag said: “You achieve your maximal heart rate a lot sooner, and you get tired a lot quicker.”

Antibiotics such as erythromycin don’t affect exercise performance. But they can in some cases cause fatal heartbeat irregularities when combined with other drugs such as astemizole, which is sold in such products as Hismanal.

Athletes who are looking for guidance on what drugs to take will have to ask a lot of questions, the doctors say. Physicians don’t think to ask about exercise habits when prescribing cold or flu medications, and athletes who buy nonprescription medications had better get used to reading labels, they say.

There may be times when it is wiser to just skip the workout, the doctors say. “The general advice is to assess whether you have symptoms from the neck up or the neck down,” Schwenk said.

It’s considered safe to exercise with neck-up symptoms such as runny noses, sneezing and coughs due to drainage, Schwenk said. But athletes should bear in mind that their performance will be worse, so they ought to cut back, at least, he said.

If the symptoms are neck-down, such as deep coughs, chest pains and gastrointestinal discomfort, it’s best not to exercise, Schwenk said. These indicate a “total body infection” and the possibility that the heart itself may be infected, raising the possibility of heart damage and even death, he said.

“One should not assume they don’t have a fever,” Wadler said. People may be misled by an oral temperature reading because these are less accurate than rectal readings.

Wadler tells patients who ask him about exercise, “Listen to your body.” If they are thinking about not working out, they probably should take a break, he said. “Upper respiratory infections tend to run three, four or five days, and missing [a workout] is not going to affect your overall conditioning.”