Rotation

Primary ways hips may be used in Taekwondo are

• Up or Down. Vertical hip movement is primarily accomplished by bending the knees, and is used primarily for stability. If you lower the hips, you increase stability, and vice versa. Some martial arts, including the International Taekwondo Federation (ITF) style of Taekwondo, use vertical hip movement as a way to increase power. According to this theory, you should raise the hips, and body mass, and then drop them to add more power to a technique. However, this is contrary to one of the primary purposes of hip movement, that of stability. If the body is raised before a technique is executed, stability decreases, which makes a person more vulnerable to attack. Also, the vertical movement is a "tell" that alerts an opponent to the initiation of an attack. Hips may also be lowered so as to lower the body to avoid an attack or to provide more leverage for a lift, such as preparing to lift an opponent with an o-goshi hip throw.
• Forward or Backward. Hips are normally moved forward and backward to help maintain balance and stability, but, in Taekwondo, this movement is also used in a forward thrusting motion to add power to a kick without committing the body into taking a forward step. When the hips (mid-section of body) are thrust forward behind a kick, such as a front kick, the body's mass is added to the force of the kick. To maintain balance during a thrust, the upper and lower sections of the body are held back. After a thrust kick, the kick may be retracted without stepping forward. As long as stability is maintained, the retracted foot may be placed anywhere the person chooses. The hips are thrust forward for power, not to increase the range of the technique. The hips are thrust forward with focus at the proper time, with only a two or three-inch movement. If the hips are thrust to reach out to the target, both power and stability are lost, which defeats the purpose of the thrust. Some say that the thrusting motion limits follow-up techniques since the hips must be brought back over the base to attain a stable base before any appreciable power may be applied to another attack or a block. While this is true, it is also a known limitation, which means the user is aware of the limitation and only uses thrusts when conditions are favorable.
• Sideways. Hips may be moved to the sides to maintain stability, to avoid a mid-section attack, or to thrust the point of the hip in an attacking motion.
• Twisting. Hips may be moved in a horizontal twisting motion around the vertical axis of the body. This is movement is primarily used to add the body's mass to the force of an attack without upsetting stability. Most martial arts, including traditional Taekwondo styles and Olympic style, World Taekwondo Federation (WTF), Taekwondo, use hip twisting (hip snap) when performing blocks or attacks. Rather than just adding more force to a technique, hip snapping adds "devastating" force to a technique. Hip twisting should not be confused with body rotation, where the entire body is rotated into a technique. See Hip Snap for more information.
• Roll. It is difficult thrust the hips behind kicks other than front type kicks, such as the front kick, axe kick, or twist kick. To add body mass to these types of kicks, such as the side kick or round kick, the hips are rolled over and inward as the kick makes impact. The hip roll adds "devastating" jolting power to these kicks just as the thrust does for front type kicks.