Sometimes people experience leg itching when they walk, exercise, or are exposed to heat. There are a number of reasons for legs to get itchy as a result of walking; if this is a recurring problem, you may want to see a doctor. When your legs get itchy, take note of the conditions of the itching, like the type of exercise you are engaged in, the temperature, and the weather. These clues can help a doctor figure out the cause of the problem.
The most common reason for itchy legs while walking is cholinergic urticaria, a fancy term for an elevation in body temperature which causes your body to react with itching, warm skin, and bumpy hives. If you have itchy legs in warm weather, saunas, and other warm conditions, you may have this condition, but you should talk to a doctor to be sure. The use of antihistamines can help to control the reaction and make you more comfortable.
If your legs get itchy as a result of cholinergic urticaria, you may need to adjust your exercise routine. You should stop the exercise which makes you itch, and adjust your workout routine and garments to keep your body more comfortable. You may also find it helpful to exercise in the early morning or late evening, when temperatures tend to be cooler. Try to avoid humidity as well, as this can increase the severity of the reaction.
In some cases, legs itch as a reaction to the clothes you are wearing. Cotton garments are the least likely to cause a reaction, so you may want to switch to loose cotton pants or shorts for walking. Some synthetics can trigger a reaction, and sometimes your legs itch in response to residual pesticides and dyes in the fabric used to make your pants. If you notice that your legs get itchy when you wear new pants, wash them and try exercising again to see if that eliminates the problem.
In rare cases, your legs get itchy as part of an allergic response to something you have eaten. This is known as exercise-induced anaphylaxis, and it can be very serious. However, an allergic reaction will be accompanied with difficulty breathing, a whole body rash, nausea, and sometimes vomiting, making it easy to distinguish from more benign causes of itchy legs. If you are suffering from a severe allergic reaction, it will become readily apparent; if you have a prescription for epinephrine to treat things like bee stings, use it. Otherwise, hail a passerby and ask for help, and make sure to specify that you think you are having an allergic reaction.