At the moment an arm technique - whether defense or attack - is executed, the other arm moves back in the opposite direction. In karate, this is called hiki te: the hand that pulls back. The hand that is pulled back moves with the same force and speed as the acting hand, thus reinforcing the action through the counter-movement.
Effective training methods provided for this are exercises in which concentration is directed to the back hand to get used to actively controlling the hiki te. Even better is to practice pulling the hand back separately, without performing an action forward. In this case, the arm that normally performs the technique simply remains inactive. It is the principle of cause and effect: every action is followed by a reaction.
Here you will find all information about the techniques in the video
