San Shou, also known as Full-Contact Chinese Kickboxing, has started to find popularity in various competitions. While the idea of San Shou has been around for ages, it has only recently started to surface and gain popularity within the United States.
San Shou, sometimes also referred to as Sanda or Lei Tai, translates to "unbound hand". The idea is to use your martial arts skills, kicking, take downs, strike techniques, sweeps, etc, that most closely resembles true fighting. Matches are normally performed on a raised platform about the size of a boxing ring. These platforms are called lei tai and hence why some people refer to this sport as Lei Tai.
Unlike point-sparring, where action is stopped once contact is made, San Shou is continual until the round is over and/or the person is knocked out. Thus, its not possible to hold back a punch or kick as it is in point-sparring.
Many of the San Shou fighters have fought in various kickboxing and/or muay thai competitions. However, the rules of each are slightly different.
Unlike the kickboxing, San Shou fighters are not required to perform a certain number of kicks in a round. The match may or may not have ropes around the raised platform, which increases the danger factor of some of these matches. In San Shou, it's not only important to try to knock the opponent out but you score points on what good martial arts techniques were successfully executed. In addition, there are bonus points scored for taking down your opponent through grappling techniques.
The difference between a San Shou fighter and a Muay Thai is more subtle. Obvious, because there is no Thailand tradition in San Shou, the fighter does not start with the Ram Muay ceremony. In addition, in a muay thai match, you will see people spending a good deal of time kicking at the shins and wearing the opponent down. While this happens in San Shou as well, it becomes rarer to see this as a technique used the more advanced the San Shou fighters are, the converse true for Muay Thai.
Finally, it's not uncommon for many San Shou fighters to be using San Shou to suppliment their Chinese martial arts training, rather than be the source of the training itself. While one can learn a lot from simply studying San Shou, the relative newness of this to most people makes it simply a subset of their total training.
San Shou rules vary slightly from tournament to tournament. The most common aspects are that fighters wear some form of shin protection and gloves. The gloves tend to resemble boxing gloves, though slightly lighter in weight in most cases. Head gear is used if the fighters are up on the lei tai for their match.
Because of the growing popularity and the recognition that this is a good way to train one in martial arts in the terms of using the techniques in real situations, fighters range from very young, probably around 6-7, to probably around the mid-30s (as most people don't like to do full contact after that point in time).