Fajin (發勁)

Fajin (發勁) is the explosive issuing of jin — the discharge phase in which trained internal force is released outward into a partner, a target, or the empty air at the end of a posture. The compound pairs fa (發, to issue, to send forth) with jin (勁, trained force). In daily curriculum use, the bare verb "fa" is often used as shorthand for the full term, especially in instructions like "fa here" or "fa with the dantian."

Fajin is one of the most-discussed and most-debated skills in the Taijiquan literature. It is often presented to the public — through videos, demonstrations, and viral clips — as if it were the whole of the art, the spectacular discharge that launches partners across rooms. The classical view is more measured: fajin is a real and central skill, but it is always the release phase of a longer cycle, not a thing that can be done in isolation. Without the receiving, the listening, the winding, and the loading that precede the release, there is nothing to issue. The discharge is the easy part; the loading is the work.

The cycle fajin sits in

A complete Taijiquan engagement cycle has roughly four phases, of which fajin is the last:

1. Reception — the partner's incoming force is captured at the contact through peng (掤) and read through ting jin (聽勁, listening).

2. Neutralization — the force is led off the centerline by lu (捋) or dissolved by hua jin (化勁), so that the partner's structure overcommits and their root is broken.

3. Loading — the practitioner's body winds up the energy that the redirection has captured. Chan si (纏絲, silk reeling) coils the fascial network; song chi sinks the breath and weight into the rear foot; dui la (對拉, opposing stretch) creates the two-directional tension that has somewhere to release into.

4. Issue — fajin: the sudden release of the loaded energy outward, traveling through the body's connected pathways and arriving at the partner along whichever gate the situation calls for (ji, an, the corners).

Skipping any of the first three phases tends to produce a muscular fajin — a sudden contraction of the shoulders, arms, and chest that looks like a discharge but is actually just a hard push. The bodily mechanics of mature fajin are the opposite of contraction: they are sudden, deep release.

External vs. internal fajin

A central distinction in the curriculum separates two models of how fajin works:

• External fajin is the spring model. The body stores elastic energy in the tendons and fascia through stretch (dui la and similar loading), and the discharge is the sudden unstretch — the spring releasing. This is real fajin and a real stage of training, and most practitioners encounter it first because it is the most easily felt.

• Internal fajin is the wave model. The discharge is a sequential wave of song (鬆, release) traveling from foot to hand, propagated by relaxation rather than by muscular snap. Each joint releases in sequence, and the wave travels as a peristaltic flow through the connected structure. This is the form fajin takes once the practitioner's internal training has matured.

Sifu Adam Mizner treats the external model as a stage to be transcended rather than the goal. The traditional formulation he uses repeatedly is "every fajin point is preceded by a point of sinking" — meaning the release that constitutes mature fajin is the release of song, the wave of let-go traveling through the structure, not a muscular tendon-snap. The external spring is what the body does before it has the internal training; the internal wave is what it does after. [1]

The Long Jin (長勁) lessons explicitly mark this transition in the Discover Taiji curriculum: the tendon-spring fajin of earlier training is superseded by the wave form, in which the release becomes a sequential flow of sung through every joint, driven by relaxation rather than muscular snap.

How fajin is trained

The student does not begin training fajin by trying to issue. They begin by building the substrate it requires:

• Form work introduces fajin as the explosive expression at the end of postures — the back fist firing as the dantian turns, the spear-tackle release, the snap at the close of a sequence. Students first feel fajin as the visible release at the close of a movement.

• Mechanical-stage training uses dui la (對拉) — the opposition-stretch loading and release — to teach the tendon-spring form: store elastic energy in the connective tissue, then snap it. This is the external model, taught explicitly as a transitional skill.

• Push hands integration layers fajin timing onto already-established patterns: the seven-point pattern, connecting hands, single push exchanges. Crucially, in connecting hands and the relaxed listening practice, fajin is deliberately withheld: the listening stage must mature before power is added on top. A student who issues during listening practice has just demonstrated that they cannot listen.

• Transition to internal mechanics comes through the Long Jin training: the foundational wave-jin from foot to fingertip that supersedes the earlier tendon-spring model. The student learns to feel the sequential release of song through every joint.

• Mature application requires almost no visible movement — Mizner's term rebounding jin names the form where fajin issues directly from a contact with no preparatory wind-up. The dantian turn sharpens and directs the release; downward fajin into a braced partner becomes possible; the cycle of song-and-fajin happens fast enough that no preparation is visible.

What separates real fajin from a push

Several markers help locate where fajin is — and is not — happening:

• The discharge is sudden but the body is not braced. A real fajin issue happens through a song body; the practitioner is fully released at the moment of issue. A pushed fajin imitator typically tenses at the moment of force, and the tension is visible in the shoulders, jaw, or chest.

• Force arrives without the partner being able to read it. Genuine fajin telegraphs nothing because there is no wind-up; the partner feels the result at the contact and not before. A muscular imitation can be seen coming.

• The issue travels through the partner, not at them. Fajin's mature form does its work inside the partner's structure — their root collapses, their structure breaks, they fall. A push works on the surface — the contact, the chest — and the partner can resist it.

• There is a clear preceding sink. Every fajin point is preceded by a point of sinking. A trained eye watching a practitioner can see the song-chi settling moment before the discharge. An untrained imitation lacks this preparatory drop.

Related concepts

Jin (勁) — trained force; fajin is its issuance

Song (鬆) — the cause of internal fajin; release, not effort, drives the wave

Chan si (纏絲) — silk reeling; the winding that stores what fajin then releases

Ba Men (八門) — the Eight Gates; fajin can express through any of the eight

The Six Levels of Song — Song Jing (Clean) is the level at which fajin issues without admixture of li

Sources

[1] Adam Mizner, Discover Taiji curriculum and seminar teachings — the formulation "every fajin point is preceded by a point of sinking", the distinction between external fajin (spring/tendon-snap) and internal fajin (wave of song), and the term rebounding jin all follow his transmission of the Yang-family internal model.

[2] The classical Taijiquan Lun (太極拳論, Wang Zongyue) and Thirteen Postures Treatise (十三勢歌訣) establish the broader principle that the art's force is mobilized through yi and qi rather than through muscular contraction, of which the internal-fajin model is a direct concrete application.

[3] The classical phrasings of fajin from Li Yaxuan's (李雅軒) writings on the Yang-family masters — describing Yang Luchan's empty fajin, Yang Banhou's sudden lightning, Yang Jianhou's light-touch sticking-and-release, Yang Shaohou's spontaneous and treacherous, and Yang Chengfu's deep-intention great sudden dantian force — articulate the same model that contemporary transmissions like Mizner's continue. [Yang Family Fajin, Discover Taiji blog, 2016.]