Several conditions can cause itchy red bumps to appear all over your body during your exercise session. These rashes can occur every time you exercise, or just appear occasionally. If left untreated, allergic reactions can potentially lead to serious, life-threatening complications. See your doctor so he can diagnose the cause of the rash and recommend treatment options.
Cholinergic Urticaria
Sweat due to the rise in your body temperature during a workout can trigger cholinergic urticaria, an exercise-related heat rash. A cholinergic urticaria rash looks like tiny bumps surrounded by red skin. It might itch or feel warm to the touch, and frequently appears on your arms and upper body. This type of reaction limits itself to a skin rash without the nausea and the difficulty breathing that can accompany anaphylaxis. It usually clears up without treatment, about 10 to 20 minutes after the end of your workout.
Exercise-Induced Anaphylaxis
Hives, an itchy skin rash composed of red, raised welts, can be one of the first warning signs of a rare, but serious, condition known as exercise-induced anaphylaxis. Exercise-induced anaphylaxis can occur as a reaction to exercise alone or happen when you mix certain foods with exercise. Foods reported to trigger this condition include shellfish, wheat, eggs, fruit, milk, fish and celery.
Exercise speeds up your heart rate and increases your blood flow. As the blood races through your body, it carries bits of food with it. These extra bits carried during exercise can trigger an allergic reaction, even in people who normally do not react to the antigens in the food item.
Warning Signs of a Serious Reaction
Signs of exercise-induced anaphylaxis include a metallic taste and tingling sensation in your mouth, as well as hives, asthma symptoms, vomiting, cramping, diarrhea, swelling of the mouth, a drop in blood pressure, difficulty breathing and loss-of-consciousness. Seek immediate medical treatment if you experience any symptoms of anaphylaxis.
Prevention/Solution
If food triggers your allergic reaction, don't eat within two hours of your exercise session. Warm up and cool down for five to 10 minutes before starting your core workout to help control body temperature spikes. Exercise indoors on hot or humid days. If running or jogging causes a reaction, try swimming instead. Take the intensity of your workout down a notch or two. Avoid other triggers, such as stress, spicy foods and hot baths or showers.
References
- The Body Odd; Allergic to Exercise?; Melissa Dahl; July 2008
- "Running Times"; Allergic to Running; Courtney Roush; Jan/Feb 2006
- American Academy of Allergy Asthma & Immunology: Tips to Remember: Anaphylaxis
- The Food Allergy & Anaphylaxis Network: Food-Dependent, Exercise-Induced Anaphylaxis
- DermNetNZ: Cholinergic Urticaria
