"Baihui acupoint" is also known as the top center acupoint and “San yang wu hui” acupoint, which is the intersection of the yang qi of Du Channel and three yang channels of foot, as well as three yang channels of foot. The "Baihui acupoint" is the intersection of all meridians, which can make essence and qi penetrate the whole body. Because the head is the intersection of yang qi and the source of all meridians, and “Baihui acupoint” is also the gathering point of the qi of various meridians, its property is yang, implying yin in the yang. So it can be accessible to the yin and yang meridians and link up the meridians of whole body, which plays an important role in regulating body to achieve the balance of yin and yang.
We all know that the practicers should keep Taiji in the mind (meditation in the way of move and quiet with yin and yang), embrace the eight trigrams (eight-line, four-square, four-corner), stamp on the five elements (forward, backward, looking left and right, stop) in the practice of Taiji, which also includes the “string bag effect” and the traditional fitness secret II open by Professor Qu Limin, namely Baihui vs. Huiyin. She pointed out that the gist of the standing is the upright body, in which there is a connotative axis, that is the axis between the Huiyin acupoint and Baihui acupoint. The ancient health experts named Baihui acupoint as the heaven door, and named Huiyin acupoint as ground households. The heaven is moving (yang) and the land is static (yin), so the heaven door should often open and the ground households should often close.
It can be seen from the above that Baihui acupoint is not only one of the main point of the Du Channel, but also the most important places in the practice of Health Qigong, as well as the gathering place of "essence, qi and spirit". "Yu Luo Xiao Tai" in the Picture of Inner Scripture is the metaphor of Baihui acupoint. So why Baihui acupoint of the Du Channel is called "Xiao Tai” in the figure? It implies a big secret of Health Qigong. There is an invisible channel between the Baihui acupoint and Huiyin acupoint, which is like the folk instruments we often play - Xiao. Only practicing to an advanced stage, can practicers get through this channel - the Zhong Channel, that is the stage of “refining the spirit and returning the virtual”. Getting through the Zhong Channel is truly means opening the “hallway” of Health Qigong completely. The ancients said that "Xiao Tai" was the place where the gods living, so the ancient health books explained that “the orifice is not an extraordinary one”.
In fact, the sound used in singing bel canto and Peking Opera are relative with the "Xiao Tai”, e.g. Peking Opera performers stress that breath to the pubic region, to resonate with the twang and the sound behind head, which inevitably affects the qi of the pubic region. It ascends from Huiyin to Mingmen, Shendao and Dazhui, through Yuzhen to Baihui, and then returns to the upper gum. The pronunciation can not only produce high vocals, but get through the Du Chanel and Ren Chanel, which is very beneficial to the health. So the physical strength and energy of many excellent Peking Opera actors are beyond the ordinary, they are rarely sick and lead a longer life. As the saying goes, "the people who are good at singing are healthy, and others may be unhealthy", “ getting through the meridians by sound".
（By Ou Liangshu）