BIOMECHANICAL FACTORS OF EFFECTIVE SEOI-NAGE IN JUDO

The purpose of this study was to compare the seoi-nage techniques between the elite and non-elite judo athletes. The information obtained helps to increase our knowledge on biomechanical factors to determine the effectiveness of seoi-nage. The motion data of the seoi-nage were collected on three male elite judo athletes and seven male student athletes using a three-dimensional motion analysis technique. The velocity generated by the hikite and hip were greater and the angles of pulling and hitting were smaller in the elite judo athletes than the student judo athletes. The comparison of the effects of the velocity and angles of pulling and hitting on the generation of the angular momentum of uke implied that these variables could be indices for coaches to evaluate the effectiveness of the seoi-nage

COMPARISON OF KINETICS OF THE LEG JOINTS IN SEOI-NAGE BETWEEN ELITE AND COLLEGE JUDO ATHLETES

The purpose of the present study was to identify biomechanical factors that could be used for the evaluation of seoi-nage technique by comparing the techniques of elite and college-level judo athletes. The motion data of the seoi-nage were collected on three male elite judo athletes and nine male student judo athletes using a three-dimensional motion analysis technique and qualitatively compared. This study found that the peaks of the knee flexion torque, knee negative power, hip extension torque and hip positive/negative power on the swing leg of elite athletes was much greater than those of the college athletes. These indicated that the knee and hip joint contributed to the mechanical energy absorption of the tori’s body in the early phase and generated the positive power in the throwing phase

COMPARISON OF KINETICS AND KINEMATICS IN SEOI-NAGE BETWEEN JUDO ATHLETES WITH DIFFERENT SKILL LEVELS

The purpose of the present study was to compare the biomechanics parameters of seoi-nage between a skilled group and an unskilled group. The motion data of the seoi-nage were collected on three male elite judo athletes and sixteen male student judo athletes using a three-dimensional motion analysis technique and groups based on skill level were compared. This study found that the anterior-posterior component of the centre of mass velocity of the tori and average anterior-posterior component of the hip velocity of the swing leg in the knee extension phase were significantly larger in the skilled group than those in the unskilled group. The information suggests that it may be more important for judo athletes to maintain the linear velocity towards an opponent than body position of the tori relative to the uke for better seoi-nage performance

KINEMATICS OF JUDO BREAKFALL FOR OSOTO-GARI

The purpose of this study was to identify kinematic parameters of breakfall for osoto-gari that can be distinguished between the experienced and the novice judokas. Eight experienced and four novice judukas volunteered to participate in the study. The motion data of the breakfall for osoto-gari were collected with a three-dimensional motion analysis technique. Our result demonstrated that there are significant differences in the hip movement pattern between the experienced and the novice judokas (

THREE-DIMENTIONAL NECK KINEMATICS DURING BREAKFALL FOR OSOTO-GARI AND ITS ASSOCIATION WITH NECK FLEXION STRENGTH IN NOVICE JUDOKAS

The objective of this study was to demonstrate three-dimensional neck kinematics during breakfall motion for osoto-gari and to elucidate its association between neck strength in novice judokas. Twenty-one novice judokas volunteered to participate in this study. The Motion data was collected using a three-dimensional motion analysis technique. We found the neck motion occurs multidirectionally during the breakfall motion. In addition, the present result showed that the peak neck angular momentum the in frontal and horizontal plane accounted for approximately 30% of the peak neck extension momentum. Finally, there was no linear relationship between the peak resultant neck angular momentum and neck flexion strength, suggesting that neck strength in the single motion plane alone may not be associated with the risk of head injuries during judo

FEAR-IN DUCED CHANGES IN BREAKFALL Kl N EMATlCS FOR OSOTO-GARI IN NOVICE JUDOKAS

Awareness of the risk and incidence of injury during the breakfall movement may lead to a perceived fear, which could be detrimental to breakfall kinematics and may even increase the risk of judo-related head injuries. Therefore, our aim was to investigate the association between the perceived fear of the breakfall movement and breakfall kinematics for osoto-gari in novice judokas. Eight experienced and 10 novice judokas volunteered to participate in this study. Motion data of the breakfall for osoto-garl was collected using a three-dimensional motion analysis technique. We found a similar trend in the joint angle curve and peak neck extension momentum for novice judokas who perceived fear of the breakfall and for those who did not. The results indicate that perceived fear of the breakfall movement may not be associated with a novice judoka's breakfall motion skill for osoto-gari

COMPARISON OF SEOI-NAGE TECHNIQUE FOR JUDO ATHLETES OF DIFFERENT SKILL LEVELS

The purpose of the present study was to compare the biomechanics parameters of seoi-nage in judo between highly skilled judo athletes and skilled ones. The motion data of the seoi-nage were collected on three male elite judo athletes and sixteen male student judo athletes using a three-dimensional motion analysis technique. This study found that the anterior-posterior component of the ankle and hip peak velocity of the tori in turning phase were significantly larger in the highly skilled group than the skilled group. In addition, the peak velocities of the ankle and hip were significantly correlated to the peak angular momentum of the tori. The results suggested that it would be useful for judo coaches to pay a greater attention to linear velocity of the lower extremities to evaluate the seoi-nage skill than the knee extension

COMPARISON OF ANGULAR FACTORS TO DETERMINE QUICKNESS IN SEOI-NAGE BETWEEN ELITE AND COLLEGE JUDO ATHLETES

The purpose of this study was to identify factors to determine the quickness of a Seoi-nage by comparing the kinematic parameters during the Kuzushi and Tsukuri phases between elite and college Judo athletes. Three-dimensional data were collected on seoi-nage performed by three male elite judo athletes and seven male local college athletes using a three-dimensional motion analysis technique. This study found that the angular velocity of the upper limb of elite judo athletes was much faster than that of the college athletes. The elite athletes performed Seoi-nage with a technique in which they rotated lower body first, and then upper body so that the rotation of the upper limb was minimized in the early part of the turning phase. This finding can help teaching of a quick seoi-nage

TRUNK BIOMECHANICS DURING BREAKFALL FOR OSOTO-GARI AND ITS ASSOCIATION WITH JUDO-RELATED HEAD INJURY RISK IN NOVICE JUDOKAS

The incidence of head injuries in novice judo practitioners is of increasing public concern in Japan. This study investigated the correlation between trunk biomechanics and judo-related head injury risk in novice judokas with the aim of developing effective injury prevention strategies. Thirty-one novice judokas were volunteered to participate the study. Three-dimensional motion analysis of the osoto-gari breakfall was performed. A multiple regression analysis was usedto test the correlation between trunk biomechanics and possible head injury risk. We found a significant correlation between the trunk COM velocity and the peak neck angular momentum (F= 13.29, df= 3, P\u3c 0.001, r= 0.77). The result suggests that controlling the trunk COM angular velocity may play an important role in judo-related head injury prevention for novice judokas

KINEMATIC COMPARISON OF THE SEOI-NAGE TECHNIQUE BETWEEN ELITE AND COLLEGE JUDO ATHLETES

The purposes of the present study were to compare the biomechanics parameters of seoi-nage between elite and college judo athletes and to produce the standard motion models of elite and college judo athletes. The motion data of the seoi-nage were collected on three male elite judo athletes and nine male student judo athletes using a three-dimensional motion analysis technique and compared. The results demonstrated that the elite judo athletes flexed the knee of the pivot leg and showed less shoulder rotation angle during the latter half of seoi-nage than the college judo athletes. The present study also revealed that the standard motion model seemed to be valid to represent the characteristics of groups’ motions