title: Impulsive force on the head during performance of typical ukemi techniques following different judo throws.
abstract: In this study, eight judo athletes who are major candidates for the Japan national team were recruited as participants. Kinematic analysis of exemplary ukemi techniques was carried out using two throws, o-soto-gari, a throw linked to frequent injury, and o-uchi-gari. The aim of this study was to kinematically quantify the timing patterns of exemplary ukemi techniques and to obtain kinematic information of the head, in a sequence of ukemi from the onset of the throw to the completion of ukemi. The results indicated that the vertical velocity with which the uke's head decelerated was reduced by increasing the body surface exposed to the collision with the tatami and by increasing the elapsed time. In particular, overall upper limb contact with the tatami is greatly associated with deceleration. In o-soto-gari, the impulsive force on the faller's head as the head reached the lowest point was 204.82 ± 19.95 kg m · s(-2) while in o-uchi-gari it was 118.46 ± 63.62 kg m · s(-2), z = -1.75, P = 0.08, and it did present a large-sized effect with r = 0.78. These findings indicate that the exemplary o-soto-gari as compared to o-uchi-gari is the technique that causes more significant damage to the uke's head.
authors.affiliation: a Department of Anatomy , Tokyo Medical University , Shinjuku , Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Hashimoto
authors.forename: Takanori
authors.initials: T
authors.lastname: Ishii
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Okada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Itoh
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D006257:Head / Q000502:physiology*; D006801:Humans; D007564:Japan; D035002:Lower Extremity / Q000502:physiology; D016139:Martial Arts / Q000293:injuries / Q000502:physiology*; D013996:Time and Motion Studies; D060726:Torso / Q000502:physiology; D034941:Upper Extremity / Q000502:physiology; D055815:Young Adult
keywords: judo injuries; sports injury prevention; sports kinesiology