In advanced traditional Chinese kung fu (martial arts), Neijin (Traditional Chinese: 內勁; pinyin: nèijìn) refers to the conscious control of the practitioner's qi, or "life energy", to gain advantages in combat.
The degree of Li force one can employ in kung fu depends on several variables such as resilience of muscles, strength of bones, speed and timing of attack and so on.
[3] On the other hand, the level of the Neijin force depends on the extent one can exercise over one's will power to release an inner qi energy.
Within the framework of Chinese martial arts, every person is believed to possess the inborn energy of qi.
The term ‘song’ can function as a verb which means to keep one's mind and body loose resilient and expanding like the consistency of cotton or clouds or relaxed yet concentrated like the sharp alertness of cats immediately before attack.