A jab is a type of punch used in martial arts. Several variations of the jab exist, but every jab shares these characteristics: while in a fighting stance, the lead fist is thrown straight ahead and the arm is fully extended from the side of the torso. This process also involves a quick turn of the torso. It is an overhand punch; at the moment of impact, the pronated fist is generally held in a horizontal orientation with the palm facing the ground. This is also called a "front punch."
Jabs are usually aimed at the face or function as a feint, to lead to a second punch. Dynamic muscles involved in the jab include deltoids, triceps, pectorals, and the serratus anterior in the extension of the arm, and quadriceps and calves in the body drive.