The present study aimed to examine the effects of uchikomi movement (a throwing drill) in seoi-nage (shoulder throw) training on the strength and thickness of the quadriceps femoris (QF) in elementary judo players. The subjects were seven boys and one girl aged 10 12 years. They had a control period of 12 weeks, and then participated in uchikomi movement in seoi-nage training (100 repetitions / day, 3 days / week, 12 weeks). Before and after the period of control and training, the isometric knee extension torque per body mass (KET / BM) during maximal voluntary contraction and the thickness of the QF were determined. The KET / BM and the thickness of the QF increased significantly after training intervention. Moreover, relative changes of the KET / BM were negatively correlated to the absolute values before the intervention. Thus, the results indicate that, the uchikomi movement in seoi-nage training can be an exercise modality for improving the force-generating capability of the QF in elementary judo players. However, the magnitude of the improvement is influenced by the force-generating capability before the intervention.

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The purpose of this study is to clarify the process of acceptance regarding the characteristics of Japanese swords in Ji-Xiao-Xin-Shu. Ji-Xiao-Xin-Shu is a Chinese book on martial arts that was written in the 16th century. There were two editions of this book, one was published around 1560-1566 (the earlier edition), and the other was published in 1584 (the later edition).
In this paper, we focused on the yao-dao and the chang-dao in those two editions of the book. The conclusions of our study are :
1. The yao-dao in the earlier edition has some special features that were adopted from the Japanese sword such as a single edge, a long thin edge, and an edge that is longer than the hilt, and a slightly curved edge. The yao-dao was used with a shield made of cane in the earlier edition of Ji-Xiao-Xin-Shu. In the traditional Chinese military idea, a sword was used with a wooden shield, and both the sword and shield were very heavy. The yao-dao and a shield made from cane were lighter than the traditional Chinese swords and shields, therefore, these new weapons replaced the old ones. Through this process, some features of the Japanese sword were accepted in the earlier edition of Ji-Xiao-Xin-Shu.
2. In the later edition of Ji-Xiao-Xin-Shu, the yao-dao and the chang-dao were described. There was an explanation about how to make the yao-dao, and some special features that came from the Japanese sword were described in the explanations. While both the yao-dao and the chang-dao have special features that come from Japanese sword, they are distinguished from each other by the total length of the sword with the chang-dao being longer than the yao-dao. The yao-dao was used with a shield made from cane, and the chang-dao was used with a rifle in the later edition of Ji-Xiao-Xin-Shu. In the earlier edition of Ji-Xiao-Xin-Shu, the chang-dao and rifle were also described, however, there were no explanations in detail. In addition, there was no guidance given on how to use the chang-dao with a rifle. In the later edition of Ji-Xiao-Xin-Shu, the special features of the Japanese sword were accepted through the military idea such as using the chang-dao with a rifle.

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The aim of this study was to clarify the effects of the expansion of the dohyo (the ring in which sumo bouts are performed) on the winning percentage for a lighter wrestler, the number of kimarite (the winning techniques in a sumo bout) and the competitive time. Forty-four pairs of collegiate sumo wrestlers, 21 pairs with a large weight difference (above 10 %) and 23 pairs with a small weight difference (below 10 %), performed 10 bouts of sumo in both a standard dohyo (diameter: 4.55 m) and an expanded dohyo (diameter: 4.85 m). We evaluated the winning number for a lighter wrestler, the number of kimarite and the competitive time in the 10 bouts.
The following results were obtained.
1) The winning number for a lighter wrestler was 4.67 ± 1.35 (average ± SD) bouts in the standard dohyo and 5.52 ± 1.33 bouts in the expanded dohyo (significant difference, P < 0.01) among the pairs with a large weight difference. On the other hand, the winning number was 4.91 ± 1.70 bouts in the standard dohyo and 5.30 ± 1.72 bouts in the expanded dohyo (NS: no significant difference) among the pairs with a small weight difference.
2) The number of kimarite was 4.90 ± 1.14 te in the standard dohyo and 4.95 ± 1.28 te in the expanded dohyo (NS) among the pairs with a large weight difference. The number was 4.00 ± 1.04 te in the standard dohyo and 4.61 ± 1.56 te in the expanded dohyo (NS) among the pairs with a small weight difference.
3) The competitive time was 8.67 ± 3.95 s in the standard dohyo and 8.80 ± 3.09 s in the expanded dohyo (NS) among the pairs with a large weight difference. The time was 8.47 ± 3.28 s in the standard dohyo and 8.92 ± 3.06 s in the expanded dohyo (NS) among the pairs with a small weight difference.
These results suggest that the expansion of the dohyo (from 4.55 m to 4.85 m of the diameter) increases the winning percentage for a lighter wrestler when the weight difference of a pair is above 10 %, but there is little affect when the weight difference of a pair is below 10 %.

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Throughout the course of the popularization of judo, Jigoro Kano refined kitoryu-no-kata (a technique in judo having a profound theory) and developed it as koshiki-no-kata. The purpose of this study is to clarify: (1) the details of kitoryu-no-kata, (2) the development from kitoryu-no-kata to koshiki-no-kata, and (3) Kano’s strategies on the popularization of kata as to which parts of kitoryu-no-kata he valued the most, the methods of the development of kitoryu-no-kata, its meaning and the development from kitoryu-no-kata to koshiki-no-kata. The results are shown below:
(1) Kitoryu is based on a state of unity between the imperturbable mind and body, which is called hontai. According to the Kitoryu jujutsu code, hontai places a strong empathies on spiritual training and harmonizing the mind and body with the universe’s energy source — ki, without being distracted by the moves of the kata or the opponent’s moves. In establishing Kodokan judo, Kano adopted kitoryu-no-kata (grappling techniques in armor which was used in times of war), as a kata with noble principles. In the kitoryu-no-kata style, Kano valued a steady posture (hontai), an imperturbable mind and techniques that disturb the opponent’s posture.
(2) Kano changed the name from kitoryu-no-kata to koshiki-no-kata sometime after 1901. When comparing the two kata, it can be seen that there are five waza (techniques) that acquired a different name and two waza (techniques) that have a reverse order. In the Kitoryu style, a 14-technique session begins and ends with a courtesy greeting. In the Kitoryu style, 14 techniques and seven mudan techniques have been recognized as different forms of kata. Although there is a movement that disturbs the opponent’s posture by grasping and holding his neck in the kitoryu-no-kata style, Kano changed it to pressing against the opponent’s chest instead— from the point of view of safety and elegance.
(3) Ever since the very founding of Kodokan, judoka have been neglecting kata. Kano tried a variety of ways to popularize kata because he felt that students should learn the principles of correct throwing techniques through kata.

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Purpose
The purpose of this research is to examine the effects of implementing a physical education class using The Instructional Book for Teaching Judo in Schools (2010) on the students’ motivation for learning.
Methods
To evaluate the change in students’ motivation to learn, the Achievement Motivation in Physical Education Test (AMPET) was used. The AMPET was developed by Nishida (1989) for the purpose of objectively verifying the effectiveness of instructions which are believed to increase students’ motivation to learn.
In order to view a broader range of the students’ changes in motivation to learn, the Original Objective Test was created by the researcher. A team of five members participated in the creation of this test, including two PE teachers who have more than fifteen years of teaching experience, a university faculty member who is an expert in this subject area, and two part-time teachers. The AMPET and the newly created test were conducted before and after teaching each unit.
Results
A significant difference was seen on the four lower rank measures of the seven subscales (each consisting of eight items) of the AMPET. These were “learning strategy”, “overcoming obstacles”, “diligence and seriousness”, and “value of learning.” A significant difference was also seen in the newly created subjective evaluation in the category of “interest in judo” and “interest in movement associated with body contact.”
Conclusion
It has become clear through the results of the AMPET and the Original Objective Test that students’ motivation for learning increased by implementing a PE class using The Instructional Book for Teaching Judo in Schools (2010).

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This study analyzes how the revised IJF competition rules effective January 1, 2009 have influenced judo competition to understand the latest trends in world judo, and to reconsider amendments to the IJF competition rules. We compared details of 476 bouts in video recordings of the France International 2008 and the Grand Slam Paris International 2009. We created specific items for analyzing competitions in an analysis sheet created in 2009.
The number of jubun (sufficient), techniques applied while both tsurite and hikite are held during kumite, was increased at a significance level of 0.1%. Also, because directly grabbing pants became a violation, the frequency of holding the ashi (leg) was significantly reduced for both the attacking competitor and the opponent. With respect to postures assumed for particular techniques, the number of techniques executed from a forward lean was reduced at a significance level of 5%.
A comparison of scoring techniques and kumite tactics before and after the revision revealed a desirable trend towards choosing techniques while holding the eri and sode and not depending on tactics holding the ashi.
This issue tended to be an improvement and the revisions of the rules were thought to have affected tactics like kataguruma and such techniques found in ashi are dependent on a technique that has yet to exist. Therefore, we presumed that this led to further revisions of the IJF competitions rules in 2010.

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