Shadowboxing

Shadowboxing is an exercise used in the training for combat sports, especially, as its name implies, in boxing. It is used mainly to prepare the muscles before the person training engages in stronger physical activity. In shadowboxing, only one person is required to participate; the participant throws punches at no one in particular. Muhammad Ali once performed a now famous shadowboxing routine next to Howard Cosell for ABC's Wide World of Sports television cameras..

Most boxing trainers prefer that their fighters do their shadow boxing before engaging in any other daily exercise routines. The main purpose of this exercise, apart from getting the muscles ready for another activity, is usually to maintain a fighter's rhythm and show the fighter how they would look at that stage of training against a certain opponent. This could be important as fighters envision themselves facing their immediate future opponents: it usually gives fighters an idea of what is, and what is not, to be fixed.

Fighters may want to do some shadowboxing of their own after their daily routines are over, either inside a boxing gym's ring, or wherever they please to at home without having to look directly at a mirror.

Shadowboxing is not, of course, limited to boxers. Many fighters from other striking based martial arts also use the exercise as part of their daily routines and aside from punches and perhaps dependent upon fighting style they will use kicks, knees, elbows, or even throws. Bruce Lee was often seen practicing his kicks in front of a mirror on his films, and he incorporated other concepts from boxing into his Jeet Kune Do style such as footwork and live sparring. Shadowboxing with swords and other weapons, referred to as a floryshe, is a major training tool among Historical European Martial Arts groups such as the Association for Renaissance Martial Arts and the HEMA Alliance.

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Wikipedia