A common belief in Daoism was that your Qi (chi) was your life-force, and you died when you ran out. Your Qi was largely determined by your level of Jing, which was largely determined by your semen levels. Semen levels were considered to be increased by sexual stimulation, but decreased by ejaculation.

To solve this imbalance, many practiced something called “injaculation” where they would put a finger over their urethra while cumming in order to push the semen back in. They believed this would send semen to the brain, causing cum-brain, which would further increase Jing. In fact, this process actually pushes semen into the bladder, where it would later be urinated out.