Taoist literature places significant emphasis on the practice of semen retention during sexual intercourse, highlighting its potential to optimize hormone secretion during sexual arousal while minimizing the loss of semen and associated hormones through ejaculation. Referred to as huan jing bu-nau in Chinese, which translates to "returning semen to nourish the body," this method has often been subject to ridicule by skeptical Westerners who interpret the term too literally, failing to grasp its underlying principles.

It is important to note that the name does not imply a literal ascent of semen up the spinal column to the brain. Rather, it signifies the reabsorption of essential components from retained semen by the male body, particularly within the soft tissues of the prostate and the spongy section of the urethra. Subsequently, these elements naturally enter the bloodstream, circulating throughout the body and providing nourishment to all organs and tissues, including the brain. Medical science recognizes that semen and cerebrospinal fluids share fundamental elements, thereby confirming that preserving semen offers the brain an increased supply of vital nutrients.

In contrast, women naturally achieve a similar effect by retaining their sexual secretions during intercourse. To enhance the reabsorption and circulation of retained semen essence, both men and women can engage in deep abdominal breathing exercises immediately after sexual activity. For men, the rhythmic massage of the prostate during deep breathing facilitates the absorption of essential components from retained semen, allowing them to enter the bloodstream. Likewise, in women, deep breathing stimulates the reabsorption of secretions retained in the vaginal region.

The practice of deep breathing following sexual relations benefits both men and women by aiding in the restoration of balance after the intense arousal of sex. Due to the heightened sensitivity of the body's energy systems, this practice significantly facilitates the harmonious circulation of Qi. For men embarking on these practices, breathing exercises also alleviate the occasional sensation of fullness experienced in the scrotum following voluntary semen retention.

By recognizing and exploring the principles behind semen retention, one can appreciate its potential benefits in terms of hormonal regulation, nutrient supply, and overall balance within the body.