Wikia

Martial arts are systems of codified practises and traditions of training for combat. They are studied for various different reasons, including improving combat skills, fitness, self-defense, sport, meditation, mental discipline, and character development.

Martial arts were still a popular area of study in the 23rd century, so much so, that Starfleet incorporated a martial arts dojo (or training hall) into the recreational facilities aboard their starships, such as the Constitution-class. (TOS novel: The Entropy Effect)