One of the issues for sport coaching research in Japan is lacking of the research on coaches' interpersonal knowledge, especially their knowledge of athlete leadership. The purpose of this study was to identify the determinants of leadership and the reality of shared leadership on each team for college student-athletes in ball games team sports. This study was conducted between December 2021 and January 2022 with 217 athletes from extracurricular ball games team sports at one domestic college (eight teams in total). The questionnaire was administered to individually rate the leadership of all teammates on the four Leadership Roles (Fransen et al., 2014) of Task, Motivational, Social and External in each team. The results of t-tests and one-way ANOVAs revealed that athletes with higher grades, hold positions and more opportunities to play in games tended to show stronger leadership. The results of the QAP test using Social Network Analysis also elucidated that different Leadership Networks were established for each leadership role in each team, indicating that Shared Leadership was being demonstrated. It was suggested that understanding the leadership characteristics of athletes and team-specific Leadership Networks will enable more effective coaching and team management.

　Many coaching theories from overseas have come into Japan and whether it is appropriate to be used in a Japanese context is rather questionable. The 4C's is a well-accepted coaching outcome of performance (competence) and psychosocial outcomes (confidence, connection, and character) in evaluating coaching outcomes and effectiveness.

　The purpose of this study was to develop what kind of outcome the winning high school kendo coaches were trying to achieve for their athletes. Semi-structured interviews were conducted on 10 experienced high-school kendo coaches and qualitative analysis was performed using SCAT. The results obtained with SCAT were inductively categorized using the KJ method and deductively categorized with 4C'S as the framework. However it was difficult to apply the results of this study to 4C's. Also, Kendo has the philosophy of “Character building”, and all the subjects talked about the approach related to it. In this case, it is conceivable that the clarification of kendo's philosophy influenced the coaching philosophy of the subjects. In order to conduct better coaching, it was considered effective to set achievable outcomes for athletes, with additional consideration towards each individual's unique culture and background.

　In this study, we aimed to develop a new endurance evaluation method specialized for judo and devised a new evaluation protocol (new protocol) applying battle rope training. The purpose of this study was to examine the physiological response of judo athletes who performing the new protocol, and to compare with other athletes. Twenty-one healthy male college students (11 judo group and 10 soccer group) participated in this study. The new protocol consists of resting for 1 minute and then swinging the battle rope alternately to the left and right for 3 minutes, three times in a row. Also, the tempo of swinging the battle rope was increased with each trial. During the new protocol, breath gas analysis and heart rate measurement were performed continuously, and blood lactate levels were measured while resting. As a result, it was clear that physiological responses during the new protocol were similar for those during judo competition, confirming maximum physiological effort in the judo group. In addition, each physiological index in the judo group showed a significant increase with each stage. It was also confirmed that judo players performed the new protocol with lower energy costs than soccer players. In conclusion, it was suggested that the new protocol could be used as a new endurance evaluation protocol for judo athletes.

　Softball is a game similar to baseball, albeit with certain different characteristics, such as the pitching style of the pitcher. In baseball, various analyses have been conducted so far on the qualities of pitches thrown by pitchers, and they have been confirmed to affect the hitting results. However, in softball, the qualities of pitches thrown by pitchers and their relationship with the hitting results have not yet been appropriately evaluated. This study aimed to identify the pitch qualities of pitchers in softball and their effect on the hitting results. First, the pitch quality of 16 softball pitchers was evaluated based on bullpen pitching. Subsequently, the hitting results, either fly ball or grounder, were analyzed in terms of the games. The results indicated individual differences in the direction of the fastball's axis of rotation in softball. In addition, although the ball velocity was not related to the hitting results, the number of effective revolutions in the direction of topspin was found to be related to the percentage of ground balls hit. Pitches with high effective rotation rates in the direction of topspin were concluded to be the cause for ground ball hitting because the downward change in the pitch exceeded that predicted by the batter. These results suggest that in softball, pitchers may possibly control the batters' hitting outcomes by adjusting their pitch quality.

　This study reports the author's coaching experience focusing on the interaction with a beginner speed skater (athlete A) who had a problem with her unstable movement in ice contact. Also, this provides useful insights for coaching beginner speed skaters by reflecting on the author's coaching experiences. Through instruction using three practice methods of 1) one leg jump, 1)' band bending, and 2) side jump. Based on the dialogue between Athlete A and the author, practices were set according to the awareness of both and the purpose of the next stage, the author intended to have her acquire “a stable movement of the supporting leg during ice contact.” As a result, the athlete A was able to clarify her goal of a stable ice contact movement by placing a band on her body part that had been a problem and being aware of it, additionally mastering the knack of keeping her toes, knees, and head in a straight line. Therefore, it was found that understanding the sports experiences of both coaches and athletes and recognizing the complementary roles may allow them to figure out knacks and generate new ways of movement. And for instructing beginners to acquire the ice landing movement at the beginning of the gliding phase, as well as making them aware of the feeling of “being able to drive”, dividing the gliding ice contact movements, and focusing attention on body parts with problems will help them concrete the movements to acquire a stable ice contact movement and become aware of the movements between the phases.

　This study aims to analyse the effects and impacts of the newly introduced 50:22 rule and goal line dropout (GLDO) rule in 2022, to obtain learnings to adapt to the new rule implementations. A total of Sixty-nine world's top-level games pre and post rule changes were used for analysis. Results showed that 1) kicking frequency increased and passing plays and contact decreased after the rule implementation. 2) The frequency and percentage of zero-pass attacks 5m out from the goal line increased and the percentage of two-passes attacks decreased before and after the rule revision. GLDO increased in-play time by 60 seconds compared to the old 5m scrum rule. 3) Although 50:22 occurs in only 30% of the analysed matches, there were changes in the aspect of kicking play by area and position, suggesting that kicking is a more important skill. 4) The defending team at 50:22 lineout and kicking team in GLDO conceded more points and took more time to escape from their own territory.