The contact sport of judo involves throwing an opponent in a variety of ways, with potential risk of concussive head impacts. When being thrown, a judo practitioner executes a break fall, theoretically protecting the head from injury. However, little research has directly measured head accelerations of a person executing a break fall in response to various throws in judo. PURPOSE: Quantify and compare head accelerations associated with six standard judo throws and corresponding break falls. METHODS: In random and repeated design, 14 judo martial artists (13 male, 1 female; age = 28 ± 9 yrs; stature = 177 ± 6.7 cm; mass = 80.3 ± 9.4 kg; rank = brown or black belt) performed five sets of six standard judo throws & corresponding break falls. The six throws were layback throw (tomoe-nage), hand throw (tai-otoshi), leg sweep (harai-tsuri-komi-ashi), shoulder throw (seoi-nage), forward leg sweep (deashi-braai), and thigh throw (uchi-mata). The participant being thrown wore a headband-mounted tri-axial accelerometer, measuring linear (g) and rotational accelerations (krad•s-2) of the head when performing a break fall corresponding with one of the six throws. Minimum threshold for registering acceleration was 16 g. RESULTS: Repeated measures one-way ANOVA and post hoc compared magnitude and frequency of accelerations of the head when performing a break fall corresponding with each of the six throws. When utilizing the linear acceleration criterion >80 g for risk of concussion, as suggested by some experts, none of the six judo throw/break fall combinations resulted in a significant head impact (incidence rate = 0%). However, when comparing all registered accelerations above 16 g threshold, hand throw (1 impact, 1.4 % incidence rate, 27.94 g, 2.8 krad•s-2), forward leg sweep (1 impact, 1.4 % incidence rate, 20.58 g, 1.59 krad•s-2), and thigh throw (7 impacts, 10% incidence rate, 28.16 ± 4.92 g, 3.94 ± 1.83 krad•s-2) had higher frequency of occurrence and magnitude of acceleration than other throws (p<0.01). Thigh throw had highest incidence rate of any throw (p< 0.01). CONCLUSION: The judo thigh throw (and break fall) had the highest incidence of sub-concussive head accelerations in the category of 20-40 g. However, none of the judo throws and associated break falls resulted in any impact considered high risk for concussion.

This document is currently not available here.