What is disharmony between Ying and Wei?
By Feng Mei LAc 09/28/2012
In TCM, Ying(nutrient) Qi move inside meridians, circle whole body fifty times daily and meet with Wei(defense) Qi, Wei Qi move outside meridians, circle whole body surface twenty five times at daytime and circle whole body internal organs twenty five times at nighttime, total fifty times daily and meet with Ying Qi too. This sentence come from <Nei Jing>: "Ying Zai Mai Zhong, Wei Zai Mai Wai, Ying Zhou Bu Xiu, Wu Shi Er Fu Da Hui". <内经>:"营在脉中，卫在脉外，营周不休，五十而复大会"。
Zi(0:00am) o'clock is the night time Ying Qi and Wei Qi meet, so, Zi is the Tai Yin meet; Wu(12:00noon) o'clock is the day time Ying Qi and Wei Qi meet, so, Wu is the Tai Yang meet. These are the two times of Ying Qi and Wei Qi meet daily. This sentense come from <Nei Jing>: "Gu Yue: Ri Zhong Er Yang Long Wei Chong Yang, Ye Ban Er Yin Long Wei Chong Yin. Gu Tai Yin Zhu Nei, Tai Yang Zhu Wai, Ge Xing Er Shi Wu Du, Fen Wei Zhou Ye".<内经>:"故曰:日中而阳陇为重阳，夜半而阴陇为重阴。故太阴主内，太阳主外，各行二十五度，分 为昼夜"。
So, disharmony between Ying and Wei, actually is the Ying Qi and Wei Qi movement not at same steps, Ying Qi is yin energy, Wei Qi is yang energy, if Ying Qi Stronger than Wei Qi, so Wei Qi is weaker than Ying Qi, the Ying Qi move faster than Wei Qi, and Wei Qi can not control the Yin Qi on surface of body at Daytime(Wu), pulse is floating, then the body Ying yin energy will like sweat come out of skin, this is Zi Han(daytime sweating); if Wei Qi stronger than Ying Qi, so Ying Qi is weaker than Wei Qi, the Ying Qi move slower than Wei Qi, and Wei Qi will push the Ying Qi out of body at nighttime(Zi), pulse is rapid and thin, then the body Ying yin energy will like sweat come out of skin, this is Dao Han(nighttime sweating); for daytime sweating treatment use herb formula "Yu Ping Feng San"; for nighttime sweating treatment use herb formula "Mu Li San".