Kanō Jigorō diligently studied “atemi-waza” (striking techniques). When he watched aikido founder Ueshiba Morihei’s martial arts demonstration in 1930, he praised that performance as the ideal of the martial arts. This study aims to analyze 689 of Ueshiba’s counter techniques against atemi-waza, as detailed in the martial arts notebooks Ken and Kon, written by the Japanese Imperial Navy Admiral Takeshita Isamu, Ueshiba’s pupil and patron in 1930, with reference to the explanations of Kanō Jigorō’s pursuit of judo as a martial art. The author will consider the similarities between Kanō’s ideal judo as a martial art and Ueshiba’s techniques. The main points are as follows: (1) From the beginning of the Kōdōkan, Kanō had taken measures to cope with atemi-waza, but he could not adopt the techniques into the randori system because of the risk of injury. Instead, he adopted atemi-waza into kata, although practitioners continued to emphasize randori despite Kanō’s repeated warnings. Kanō feared the practitioners’ bad posture. Kanō believed that an essential element in judo as a martial art was to dodge the opponent’s unpredictable atemi attacks by using nimble body movements. He therefore stressed the importance of a natural posture. Kanō thought that a natural posture was ideal because it could flexibly respond to any atemi attack. (2) The opponent’s atemi-waza in the 689 techniques highlighted by Takeshita included both short- and long-distance attacks. These techniques made the opponents’ atemi attacks, which included chops, punches, and kicks, ineffective through the use of nimble body movements and the skillful use of the hands in situations where the practitioner was either standing or sitting. Based on a natural posture and these defensive techniques, Ueshiba used dangerous atemi-waza or skilled throwing techniques that were influenced by Daitō-ryū Aiki-jūjutsu. It becomes clear that one of the features of Ueshiba’s skills, as praised as an ideal martial art by Kanō, was to cope with the opponent’s atemi attacks by using a natural posture and nimble body movements, both of which were essential elements in judo as a martial art according to Kanō.
This study aimed to discover new features of injuries during judo practice. The types of injury were reportedly different between age groups: in high school students, dislocation and fracture around the shoulder joint occurs frequently, while knee sprain was common in university students. On investigation, a high number of fractures and dislocations around the shoulder joint were observed in a group of adults. This suggests that the part of body or type of injury is different depending on the competition level of individuals. The majority of injuries were caused by being thrown, which can be a major risk factor for non-experienced individuals practicing judo. Therefore, teachers require a better understanding of the features of judo practice.