At this, already very high level of Taoist energy work, the sexual energy Jing Chi (creative power) is transformed into life force. The key secret of these formulas is that the usual positions of fire and water are reversed mentally in the physical body to release sexual energy. The spread of sexual energy throughout the organism can be thought of as water vapor rising as soon as the water begins to boil on the fire.
By interchanging the positions, the heat of the body fire gets under the cool of body water. Without this interchange, the fire simply blazes up and heats or burns the body from within. The water (the sexual fluids) tends to flow down and leave the body. When the water dries up, the body breathes its life. The process of evaporation can be extended over a long time.
The moist warm steam produced carries tremendous energies and is extremely beneficial to health. The glands, as well as the nervous and lymphatic system are regenerated, the circulation of energy and body fluids intensified. (Harald Röder 2013)
The high practices of Inner Alchemy are taught by Grand Master Mantak Chia in the Darkroom, following the tradition of Taoist masters meditating in dark caves to keep the mind free from distractions.