The "I'm allergic to exercise" joke is as old as time (or as old as wellness culture, at least). It's something our parents, our friends, and we ourselves have uttered on those days when we feel particularly sluggish and lazy. We’re especially apt to use it on those days when we drag ourselves to the gym, only to stare at the treadmill in dread. It's funny, mostly because it's dramatic, outlandish, and obviously an excuse, right? According to Greatist, for some people, not so much. As it turns out, having an allergic reaction to exercise is an entirely real and dangerous possibility for certain people. In fact, in extreme cases, it could be deadly.
The scientific term for this "exercise allergy" is exercise-induced anaphylaxis (or EIA for short). Although it's rare, this condition spurs your body to mount an allergic response to prolonged or strenuous activity, resulting in itching, swelling, and trouble breathing. Keep reading to learn more about this condition as well as why it happens.
"Anaphylaxis is a severe allergic reaction that causes the allergy cells in your body to release a bunch of histamines, which typically help your body get rid of allergens," says Purvi Parikh, MD, an allergist and immunologist with the Allergy & Asthma Network, in conversation with Greatist. "When someone goes into anaphylactic shock, their bloodstream is flooded with inflammatory cells that overwhelm the body, bringing on itching, nausea, and making it hard to breathe."
So why exactly does this happen to some people while exercising? Well, it has to do with existing food allergies, not technically the activity itself. "With EIA, people find that within two to three hours of eating a certain food, they’ll develop an allergic reaction," Parikh says. "It’s typically foods they could eat normally with no reaction, but working out with those foods in their system is what triggers the reaction." So even though a specific food is the root cause, the exercise is what ultimately spurs the allergic response.
Because this condition is so rare (Greatist notes only 50 of every 100,000 people have it), there hasn't been much research done to explain why this happens. All we know for sure are the symptoms. "They could be as simple as flushing, fatigue, or itchiness, or more serious, like respiratory distress, throat closure, hypertension, or cardiovascular collapse,” Gerardo Miranda-Comas, MD, assistant professor of rehabilitation medicine at the Icahn School of Medicine at Mount Sinai, told the publication.
"A board-certified allergist can identify which foods you’re sensitive to—wheat, celery, and shellfish are the most common, but EIA can happen with any food,” Parikh says. If you're exercising, whether yoga, running, or strength training, and you experience any of the symptoms of an allergic reaction, you should stop and call your doctor. "If someone does suffer from EIA, we’ll usually prescribe them an Epi-Pen, antihistamines, and an inhaler if needed,” Parikh says. “And once we know the allergy, we recommend they don’t eat anything with that ingredient three to four hours before exercising.”
So, yes, even for those people who experience exercise-induced anaphylaxis, working out is still completely possible. In other words, even though it's a real thing, even being "allergic to exercise" isn't a good excuse for avoiding workouts.