Video showing how fast the Wing Chun moves can be. Lightning reactions to attack.
Because of the emphasis on the center line, the vertical fist straight punch is the most common strike in Wing Chun. However, the principle of simultaneous attack and defense (Lin Sil Die Dar) suggests that all movements in the Siu Nim Tau with a forward execution flow into a strike if no effective resistance is met, without need for recomposure. Other explicit examples of punches can be found in the Chum Kiu and Bil Jee forms, although these punches may appear to be superficially different they are simply the result of the punch beginning from a different origin position while following the same fundamental idea, to punch in a straight line following the shortest distance between the fist and the opponent.
The vertical punch is the most basic and fundamental in Wing Chun and is usually thrown with the elbow down and in front of the body. Depending on the lineage, the fist is held anywhere from vertical to horizontal (palm side up). The contact points also vary from the top two knuckles, to the middle two knuckles, to the bottom three knuckles. In some lineages of Wing Chun, the fist is swivelled at the wrist on point of impact so that the bottom three knuckles are thrust forward adding power to the punch while it is at maximum extension.
The punches may be thrown in quick succession in a “straight blast” or “chain punching”. When executed correctly, it can be used as a disorienting finisher.