Fa jin

Fa jin, fajin, or fa chin (fā jìn, 發勁) is a term used in some Chinese martial arts, particularly the neijia (internal) martial arts, such as Xingyiquan, T'ai chi ch'uan (Taijiquan), Baguazhang, Bak Mei and Bajiquan.

It means to issue or discharge power explosively or refining the explosive power, and is not specific to any particular striking method. Jìn (勁), or "power", is often confused by Westerners with the related concept of jīng (精), which literally means "essence." To generate the fa jin it is necessary to create a spiral from Dantian towards the limb or body part (e.g. shoulder, head, hip) that will perform the technique with explosive force (Bàofālì 爆發力).

Jin describes the ability to generate force. If a person is off balance, they have no jin. The way it is explained is that the qi cannot penetrate the muscle to produce force. From a biomechanics perspective, the person in a weak physical state. Jin and qi are inherently combined.

In the practice of Taiji quan it is a description of a technique, generally indicating a sudden release of energy obtained by the coordinated movement of the entire body. Every technique can express fa jin, not just kicks, punches, elbows and knees, but also holds, levers and projections. Essential is the mastery of the techniques of chan ssu jin Silk reeling. The Fa jin released during exhalation is almost unconscious. This technique is referred to in the forms of training school as the Lao Jia Chen Pao Chui (ancient cradle, cannon fist, one of the two original forms Chen-style t'ai chi ch'uan), while in Yang school, especially for those who have a direct lineage to Yang Shaohou the fa jin is added to techniques to release the stored energy.

A main principle in creating fajin, is using your dantian. The dantian is thought to be the storehouse of your energy and can be used in striking. One technique described by Master Wang Jianqiao for developing fajin is by breathing into your lower abdomen (dantian) and creating a pressure. When you strike and squeeze your lower abdomen tight so that the core becomes compact, unifying the torso. This actively engages more of the muscle fibers to generate more force.

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Wikipedia