The question of why fighters in WTF tournaments and the Olympics utilize a particular stance and guard was asked in another thread. Rather than derail that thread, I started this one. I have not competed in many several years and have never competed with electronic hogu, so my information may not be the most up to date, though the essentials haven't changed. World Taekwondo Federation sparring rules mandate that participants wear a hogu and homyun. The hogu protect the torso and are reversible; one side red, the other blue, which allows participants to be easily distinguished by color. The primary reason for the hogu, however, is to allow kicks to the torso above the belt and below the chest without undue injury to the person receiving the kick. The homyun protects the head. Electric hogu to facilitate scoring is utilized at the national and international levels in order to facilitate consistent scoring. The benefits of electric scoring have been a source of debate and is outside of the context of this thread. Kicks are the primary technical element used for scoring and the rule set is set up to both emphasize kicks and to make use of the extended range kicking allows over hand techniques. Kicks to the head or face score three points and punches are not allowed above the torso area. Blows to the body, be they punches or kicks, are worth one point, but spinning kicks, including the back kick, are worth two. Strikes must be delivered with "trembling shock" in order to score. Matches are continuous, meaning that after a score is tallied, the match is not stopped to reset the opponents. Because blows to the head are worth more points, high kicking is encouraged. Because spinning kicks to the body are worth more points than non-spinning kicks, these are encouraged. While punches to the body are worth one point, it is difficult to score with punches. Punches tend to be used more to off balance an opponent and/or to set him/her up for a kicking attack, or to create some space. Only straight punches to the body are scored. Because the body is both closer and much larger than the head, it is still the most obvious target. The midsection of the torso is the scoring area, and it valid around the body excepting the spine, so there are a lot of opportunities to score on the body. Because kicks naturally have more power than punches avoidance of kicks, particularly head kicks, is the preferred method of defense. Because blocking a punch means potentially opening up one's self more for a kicking attack, punches are avoided as well. Blocking kicks also carries greater risk of injury to arm/wrist/hand due to the greater force delivered by the kicking limb. For these reasons, participants tend to maintain a low guard. This keeps the body perpetually protected. Athletes also "bounce," allowing for rapid movement in any direction without taking a step and for rapid changes of left/right stance. This facilitates fakes with the legs and prevents you from having to cross your feet as you move. It also means fewer changes in stance and fewer chances for an opponent to take advantage of those changes. At the conclusion of the match, the player with the most points wins. This is hardly detailed description of the rules; if you want that, you can find it here: http://www.wtf.org/wtf_eng/site/rules/competition.html. Obviously, the rule set is not designed to emulate a "real fight" but was designed to offer a martial sport with a flavor and feel different from that of karate, kickboxing, or boxing, and which would also pay homage to Taekkyeon, a Korean kicking game. WTF rules provide a distinctly Korean game that emphasizes high, full contact kicking. For those who have questions about the rule set, I hope that this is helpful to you. For those who are more directly involved in WTF competition than I am, please feel free to enrich this topic with your knowledge.