How about running in rainy days? What are the advantages and disadvantages?

Not good! Because, running in rainy days. First, while your heart load is increasing, the temperature of the rain is too low, which will increase the burden on your heart; Second, exercise will increase your breathing frequency, and rain will hinder your breathing; Third, when it rains, most of the oxygen ions in the air are absorbed by the rain, which is not conducive to aerobic exercise such as running (for a long time)!