Beginning from Xiao Man, the summer harvest crops such as barley and winter wheat have already fruited, the grain has gradually become full, but it is not yet mature, so it is called "Xiao Man" (meaning "grain full"). The solar term of Xiao Man is right at the end of May, when the temperature significantly increases. If one sleeps in cool places due to hot weather, it will surely trigger rheumatism, dampness dermatopathy and other diseases.