Regular exercise is an important part of staying healthy. It strengthens cardiopulmonary (heart and lung) function and delays the degenerative effects of aging. It is also believed to boost the immune system.
However, those with allergies often need to take special precautions during exercise. Pollens in the air, stinging insects and pollutants are just a few of the allergens that can be encountered during exercise. Exposure to such allergens can trigger relatively minor symptoms, such as a runny nose or itchy eyes. In the worst cases, allergies can cause the person exercising to experience breathing difficulties.
Some people with allergies may be tempted to skip exercise altogether, believing it is not worth risking discomforts and potential dangers. However, the benefits of exercise far outweigh the relatively low risks associated with allergies that are well-controlled. Before beginning any exercise plan, those with allergies should seek the advice of a physician.
About allergies & exercise
Allergies associated with exercise involve the typical mechanism of any allergic reaction. An allergic reaction is the immune system’s attempt to defend the body from a perceived threat that, in reality, is harmless. During this process, chemicals such as histamines are released into the body, triggering allergy symptoms. Symptoms of this reaction may include itchy eyes, runny nose and sneezing. In some cases, the reaction is more extreme, resulting in hives, eczema (skin inflammation) or breathing difficulties.
Allergies that flare up during exercise often stem from exposure to the allergens associated with allergic rhinitis (hay fever). These include pollens, molds, dusts and animal dander. The severity of these allergy symptoms can range from merely being a nuisance to severely impacting performance (especially in athletes competing at high levels). In rare cases, allergies triggered by exercise can cause potentially life-threatening reactions.
Even minor symptoms can impact an individual’s motivation to continue to exercise. Breathing through the nostrils is an important aspect of exercising comfortably and safely, because the nose and sinuses warm the air and filter out irritants. A person who is congested will breathe more through the mouth, which can introduce irritants and allergens to the bronchial tubes and lungs.
Despite such risks, most experts strongly encourage those with allergies to continue or begin healthy exercise routines. Moderate exercise is believed to increase immune system efficiency, thus potentially decreasing the likelihood of allergic reactions. Over-training, however, is believed to have the opposite effect and actually decreases immune system efficiency. Therefore, a healthy and balanced exercise routine is important to the overall health of people with allergies.
Potential allergen exposure during exercise
The environment is the chief source of allergens that may cause trouble during exercise. A person who suffers from allergic rhinitis may react after encountering ragweed when pollen counts are especially high. Another individual may suffer from hives after being exposed to algae while swimming in a lake.
Examples of airborne allergens include:
- Animal dander
Exercising outdoors exposes people to insects, thereby increasing the likelihood of an insect bite or sting occurring. Certain types of insects release venom through stings and bites that can cause anaphylaxis, a whole-body allergic reaction that is potentially life-threatening. Stinging insects include:
- Yellow jackets
- Paper wasps
- Fire ants
It appears that eating certain foods prior to exercise may increase the likelihood of an allergic reaction in the life-threatening form known as exercise-induced anaphylaxis. For this reason, patients who have experienced any kind of exercise-induced allergy or anaphylactic symptoms should take careful note of what they had eaten prior to the episode. By avoiding or controlling the consumption of these foods in the future, patients can help avoid further reactions.
Contact dermatitis is an allergic reaction with a rash consisting of itchy, red, small papular vesicles (a pimple-like blister) that ooze and crust. It usually appears several days after exposure, making it harder to track down the allergen responsible. However, the rash location sometimes can offer clues.
Sources of contact dermatitis during exercise include:
- Vegetation, such as poison oak or poison ivy encountered while running in a field or on the beach
- Elastic, such as that found on waistbands of athletic shorts
- Rubber or dyes in athletic footwear
- Paratertiary-butylphenol formaldehyde resin, found in athletic tape used in sports such as football and hockey
Recent studies have shown that air pollution can have a significant effect on a person’s lungs. Specifically, research suggests that certain pollutants can trigger bronchoconstriction (tightening in the airways) in sensitive individuals, making it more difficult to breathe. Depending on the area, exercising outside may bring a person into contact with air pollutants and increase the chance of severe bronchoconstriction occurring during an allergy or asthma attack.
Related allergies and conditions
Exercise can sometimes create symptoms that mimic allergies, but which are in no way related to an allergic reaction. For example, exposure to cold or hot conditions during exercise can sometimes trigger hives and angioedema, symptoms that also appear as the result of an allergic reaction. However, weather conditions are not the only trigger for these conditions. Just the mere act of exercising is enough to trigger hives and angioedema in some people.
Similarly, pool chlorine can trigger eye irritation or breathing difficulties in swimmers that appears to be related to allergies even though it is not. And sometimes, a reaction to a true allergen such as pollen may leave an individual more susceptible to the effects of pollutants or other factors that normally do not cause a reaction.
Conditions related to exercise and allergies include:
- Hives. Red, swollen patches of skin that occur in groups and may burn, sting or itch.
- Angioedema. Swelling that occurs beneath the skin instead of on the surface.
- Allergic conjunctivitis. Inflammation of the conjunctiva, the tissue lining the inside of the eyelid.
- Allergic rhinitis. Inflammation of the mucous membrane that lines the nose due to allergic reaction to an airborne substance.
- Contact dermatitis. Allergic skin reaction that manifests itself as a rash of itchy, red, small blisters that ooze and crust.
- Food allergy. Disorder characterized by the response of the immune system to certain foods.
- Exercise-induced asthma. Asthma symptoms triggered by exercise.
- Exercise-induced anaphylaxis and urticaria. A rare form of physical allergy triggered by exercise at all levels of exertion.
Signs and symptoms of allergies & exercise
The nature of symptoms that occur during exercise will differ depending on the allergy that is being triggered and the severity of the reaction. In many cases, symptoms will be limited to those associated with allergic rhinitis (hay fever), such as:
- Watery eyes
- Runny nose
- Sore or itchy throat
Others will experience symptoms of contact dermatitis, including a rash of itchy, red, small vesicles (a pimple-like blister) that ooze and crust.
In rare cases, symptoms will manifest in the form of anaphylaxis. This is a whole-body allergic reaction that affects two or more body systems, such as the skin, lungs, nose, throat, gastrointestinal tract and heart. Symptoms include:
- Severe itching of the eyes and face
- Feeling anxious
- Palpitations (a strong, fast, irregular, abnormal or “galloping” heartbeat)
- Slurred speech, tongue swelling and inability to swallow
- Swelling of the throat
- Rapid or weak pulse
- Red or swelling skin
- Hives (including on the lips, eyelids, throat and tongue)
- Nausea or vomiting
- Bluish tint to skin (cyanosis), including lips or nail beds
- High-pitched breathing sounds
- Nasal congestion
- Breathing difficulty
Most cases of anaphylaxis involve either cardiovascular or respiratory symptoms. The pattern of symptoms also typically remains the same for an individual from episode to episode. Without immediate emergency treatment, anaphylaxis can quickly become life-threatening anaphylactic shock. More advanced signs and symptoms include:
- Collapse or loss of consciousness
- Loss of bladder control
- Cardiac arrest
- Respiratory arrest
A physician is likely to compile a medical history of the patient and to ask about symptoms experienced during exercise. Even when an allergy is suspected, a physician will want to rule out other potentially more serious conditions before proceeding with treatment. For example, shortness of breath during exercise could be related to an underlying heart condition, poor athletic conditioning or pulmonary problems rather than an allergy. In such cases, a physician may want to perform a chest x-ray or an echocardiogram (uses sound waves to create pictures of the heart and its vessels) to rule out potential heart ailments or other conditions.
If an allergy diagnosis does appear likely, several tests may be administered to try to pinpoint the allergen responsible for symptoms. Tests may include:
- Allergy skin tests. A small amount of an allergen is introduced to the patient’s skin to determine if the person is allergic to that allergen.
- Allergy blood tests. A sample of the patent’s blood is tested for substances that indicate an allergic reaction has occurred to a specific allergen.
- Food allergy tests. Patients may be asked to avoid (or, in rare cases, to ingest) specific foods according to a timetable to determine if allergic reactions can be avoided.
- Other related tests. Any number of tests that may be used in diagnosing the causes of allergy-related symptoms, including those to determine lung or nasal function and to rule out other causes of allergy-like symptoms (such as infection).
Treatments for exercise-related allergic reactions will depend on the type of reaction and the symptoms present. For symptoms associated with allergic rhinitis, a physician might prescribe:
- Inhaled anti-inflammatories
Antihistamines and anti-inflammatories can be taken to prevent symptoms before they occur. Over-the-counter and prescription medications should never be taken without consulting a physician first. Some drugs may be dangerous when combined with certain forms of exercise.
In cases of allergic contact dermatitis, patients may find relief from applying wet compresses to blistering rashes. Prescription corticosteroids or antihistamines also may be helpful in moderate to severe cases.
Individuals experiencing anaphylaxis (a whole body allergic reaction that affects two or more body systems) require immediate medical attention. An injection of epinephrine is required to reverse the patient’s symptoms. This drug relaxes the smooth muscle tissue in the lungs, speeds up the heart rate, slows the appearance of hives and welts on the skin and reduces overall swelling. Those with a history of anaphylaxis may receive a prescription for an allergy kit. This kit contains a dose of the drug epinephrine, which the patient can inject into the thigh during an emergency.
Those who have insect allergies or severe reactions to other allergies may be encouraged to undergo allergy shot treatment (immunotherapy). This treatment is extremely effective in preventing anaphylactic shock. The goal of immunotherapy is to build up a patient’s tolerance to the allergen. For example, an individual at risk from insect stings would receive very low-dose injections of the insect venom until they build up a tolerance to it. Once the tolerance has been established, the likelihood of suffering an allergic reaction to a sting is substantially reduced.
Preventing allergic reactions during exercise
The best way to prevent an allergic reaction during exercise is to identify the allergen responsible for symptoms, and to avoid exposure to that allergen as much as possible. This may mean choosing a sport or activity that does not involve exposure to the allergen.
For example, someone allergic to ragweed may consider swimming at an indoor pool instead of jogging near a wooded or grassy area. Sometimes, a person may be able to continue an activity by simply shifting the environment. For example, individuals with pollen or insect allergies can reduce their risk for allergy symptoms during exercise by running or playing tennis indoors, while those with dust allergies would benefit from heading outdoors.
Generally, activities that involve continuous activity, such as running, can cause more reactions than stop-and-go activities. The time of day and the weather can also play a factor. For instance, pollen counts are usually lowest during wet, chilly periods and in the evening hours. They tend to be highest in the mornings, and on warm, dry, windy days.
Of course, switching an activity or environment is not always possible or desirable. Those who are at risk for an allergic reaction during exercise should take the following precautions:
- Always warm up and cool down for at least 15 to 30 minutes before you begin strenuous activity.
- Pay close attention to symptoms. Slow down or stop exercising when appropriate.
- Choose appropriate activities. Fewer symptoms are likely in sports requiring short bursts of energy (e.g., basketball, tennis, swimming) than those that demand long periods of constant exercise (e.g., long-distance running, soccer).
- Do not exercise during respiratory illness (e.g., respiratory tract infection). The nasal and sinus passages filter out pollutants, irritants and allergens from the air, as well as warm and humidify the air before it is inhaled. Therefore, patients with illnesses that cause nasal and sinus congestion should avoid exercising until their symptoms subside.
- Limit exercise when severe allergy symptoms are present. Allergy symptoms may be aggravated by increased activity.
- Watch the weather. Try to exercise when pollen counts are low. Cold, dry conditions can irritate bronchial tubes, so try to exercise indoors at such times.
- Cover the mouth with a scarf during cold weather. This warms the air entering the airways.
- Avoid pollution. Try not to exercise where traffic levels are high, or when smog or other air pollution is a factor.
- Keep away from open windows and doors while exercising indoors. This can help people with allergies reduce their contact with pollen and other outdoor allergens.
- Exercise on a mat. Patients with allergies should avoid exercising directly on carpeting, which can contain indoor allergens such as dust, dust mites and animal dander. Placing a mat over an area of the carpeting may help prevent allergy symptoms while exercising indoors.
- Understand the dangers specific to your allergy. For instance, those with serious insect allergies should avoid wearing bright-colored clothing or strong perfumes that may attract insects. Also, avoid exercising near flower beds, bodies of water or other areas likely to attract insects.
- Be prepared. Those with known anaphylactic reactions triggered by exercise or other factors (e.g., insect stings) should carry an epinephrine shot in case of a life-threatening reaction. In addition, any work-out partners or instructors should be made aware of the allergy and be informed of what to do if a reaction occurs.
- Wear a medical alert bracelet with a list of allergies and medications required in case of a medical emergency.
- Always follow a physician’s advice. For instance, some patients may be instructed to use an inhaler 15 minutes before exercise to reduce the risk of reactions.
Questions for your doctor
Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctors the following questions regarding exercise and allergies:
- What tests will you use to determine the cause of my symptoms?
- What treatments are available to me?
- Is it safe for me to exercise?
- How can I prevent an allergic reaction during exercise?
- Should I carry an epinephrine shot when I exercise?
- Which types of exercise are best for me?
- Is it best for me to exercise outdoors or indoors?
- Should I limit the length of time I exercise because of my allergies?
- Should I limit the frequency of exercise because of my allergies?
- Which symptoms should I immediately report to you?
- For which symptoms should I seek emergency medical attention?