Sanshou (散手), also known as San Da (散打), Duan Shou (断手) or free fighting is the combat aspect of Martial Arts. In general it used to refer to the combat aspect of Traditional Chinese Martial arts but today has also become a Competitive sport. Modern San Da combines full-contact kickboxing, which include close range and rapid successive punches and kicks, with wrestling, takedowns, throws, sweeps, kick catches, and in some competitions, elbow and knee strikes (Professional San Da).
Sanshou's competitive history involved barehanded or lei tai fights in which no rules existed. However, even sanshou as a competitive event developed in the military as these bouts were commonly held between the soldiers to test and practice barehanded martial skills, ability and techniques. To the untrained eye, Sanshou/Sanda appears much like Kickboxing or Muay Thai, but it is much more and includes many more striking variations (inclusive of different kicks and punches) and throwing/grappling techniques.
In Chinese martial arts we emphasize the four combat focuses of Ti, Da, Shuai & Na (Kicking, Striking, Throwing & Grappling), Sanshou/Sanda therefore incorporates those concepts into its fighting repertoire in consideration of the constraints presented by the rules and regulations of competition.