Hi there,
Thanks for your query.
From the information provided, you are apparently suffering from allergic problems. This includes allergic, 
exercise-induced asthma, as well as, 
atopic dermatitis which is due to sudden changes in temperature (called thermal-induced 
allergic dermatitis); or, cholinergic dermatitis.
Running or severe physical exertion causes sudden change in body temperature, leading to bumps' formation.
A regular daily intake of anti-histaminics (such as levoceterizine + 
montelukast) and an anti-cholinergic drug will certainly give you relief.
Consult your doctor and apprise him of my opinion. I am certain that he will agree with me, order required tests, and- based on the reports-  will prescribe suitable/modified treatment as advised.
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Dr. Rakesh Karanwal