noun
striking practice with intentional openings
Martial arts training drill where the attacker strikes through deliberate openings left by the defender, often used in kendo and other disciplines.
剣道の稽古では、打ち込み稽古で面や小手の打突を繰り返す。
In kendo practice, we repeatedly strike the men and kote during uchikomi-geiko.
打ち込み refers to the striking action itself or repeated striking drills, while 打ち込み稽古 specifically denotes the training method involving intentional openings.
掛かり稽古 is a continuous attacking drill against a resisting opponent, whereas 打ち込み稽古 focuses on striking through openings with less resistance.
Compound of 打ち込み (uchikomi, 'striking') and 稽古 (keiko, 'practice'). The term is specific to martial arts training contexts.