The purpose of this study is to grasp the actual situation of troubles that threaten the integrity of sports in Japan by investigating the frequency of these troubles and their predictive experiences among athletes and coaches, and by analyzing the differences in position and gender. The results will be used to identify problems that should be addressed on a priority basis. Based on these findings, we will clarify the priority issues and their targets and discuss how to address them from a coaching perspective to maintain sports integrity.

　A questionnaire survey was conducted using an application targeting athletes and their coaches who are designated as Olympic-level or above. The survey included questions about the frequency of occurrences within the past two years and the frequency of two types of predictive experiences. The distribution of responses from athletes and coaches was analyzed by cross-tabulation.

　The results showed that 14 (13.7%) of the athletes had experienced “power harassment (damage)” and 15 (14.7%) had been troubled by it, which was significantly high. Similarly, 22 (15.4%) of the coaches had experienced power harassment (victimization) and 22 (15.4%) had been troubled by it, indicating that the number of respondents who had experienced power harassment (victimization) was significantly high.

　Next, the analysis of positional and gender differences in power harassment (damage) revealed that 10 (33.3%) of the female coaches had experienced power harassment and 10 (33.3%) had been troubled by it, significantly more than the male and female athletes and male coaches.

　Previous surveys on power harassment have only focused on direct experiences to understand the actual situation. However, considering the high frequency of predictive experiences prior to the occurrence of problems, power harassment may be a more serious issue than previously known. Based on the results of the comparison of occurrence frequencies among different problems, it can be said that power harassment (damage) should be given priority when dealing with top athletes in Japan. Additionally, by including coaches as subjects, it was revealed that even coaches experience power harassment, indicating a different reality from what has been pointed out in the past.

　The aim of this study was to present a case study of an expert pitching coach in collegiate baseball, highlighting practical knowledge for enhancing pitching skills. Data on the expert pitching coach were collected by recording coaching behaviors using a video camera and capturing verbal interactions with an IC recorder. The total duration of data collection was 755 minutes, including 396 minutes devoted to coaching the first team and 359 minutes spent with the second and third teams. The collected video and audio data were analyzed in detail using quantitative methods. The findings revealed that the expert pitching coach adjusted their coaching strategies based on the skill level of the players. Furthermore, notable differences were identified in the methods of communication and language used depending on the target group. Specifically, the study yielded the following insights: 1. For less-skilled players, the expert pitching coach employed nonverbal communication strategies such as “demonstration of ideal movements” and “manual guidance through physical contact” to facilitate the players' ability to imitate optimal movements and create an environment conducive to visualizing improvements. 2. For highly skilled players, the coach encouraged reflective thinking through the use of “open-ended questioning” and emphasized the term “personal sensation” to elicit the players’ tacit knowledge and experiential understanding.

　The purpose of this study was to gain knowledge into the technical factors that maintain the mechanical effectiveness in the second half of the men's 20-km walking race. Video data in the first and second halves of the race were collected by two high speed cameras. 58 subjects were analysed, and the kinematic and energetic variables were calculated using the three-dimensional DLT method. The differences between the first and second halves of the race about these variables were calculated. Based on amount of change in the walking speed index and the effectiveness index (EI), the subjects were classified into three groups by cluster analysis. Differences in the amount of change between the groups and the trunk movement within the groups were examined. The results showed that among the athletes who maintained the walking speed index, those who lowered their EI had significantly greater trunk forward leaning during the entire support phase in the second half of the race. In addition, the amount of change in the velocity of center of gravity during the deceleration phase in the support phase was increased. Furthermore, the torsion angle of the trunk joints increased significantly, and the mechanical energy transfer decreased. These results suggest that it is important to control changes in trunk forward leaning and trunk joint torsion to maintain mechanical effectiveness under the fatiguing conditions of the latter half of a men's 20-km walking race.

　The present study aimed to determine the relationship between ground contact time during sprinting and long jumping, and during jumping tests such as the RJ and RDJ. The main findings of this study are as follows:

(1) Significant positive correlations were found between ground contact times in RJ and RDJ for all jumping tests, for both double- and single-leg conditions.

(2) No significant correlations were observed between ground contact time during sprinting and during any of the jumping tests. Similarly, no significant correlations were found between ground contact time in the long jump and in any of the jumping tests.

　These results suggest that the relationship between ground contact time in jumping tests such as RJ and RDJ, and in actual performances such as sprinting and the long jump, is weak. They also suggest that, while intra-individual ground contact time characteristics may be similar between simple jumping exercises, they are not between sprinting and jumping events and jump tests.

　This study is about the “Face to face type” of boxout used as a means of obtaining defensive rebounds in basketball. The author classified the boxout into “Behind type,” “half type,” and “Face to face type. Although the “Face to face type” is considered effective against strong rebounders such as big men, few teams choose this type. In this study, the “Face to face type” boxout against strong rebounders was taught to a college women's basketball team, and its effectiveness in games was verified. As a result, no difference was observed in the defensive rebound acquisition rate depending on the type of boxout. However, the “Face to face type” boxout reduced the rebound acquisition rate of strong rebounders. This may indicate that “Face to face type” boxout, which allows the player to focus only on the strong rebounder, is more effective than other types.

　This study presented a case study of coaching a female high school kendoist to acquire her signature techniques. It provided practical insights for improving technical and tactical coaching at the developmental stage. An interview was conducted with a coach who trained a female kendoist in high school. This athlete later went on to compete at the international level. The coach's narrative was analyzed qualitatively.

　The findings were as follows:

(1) The coach identified the athlete's strength in executing an excellent “Men” strike, but also recognized her weakness in being countered by opponents' “Do” techniques. To address this weakness, the coach helped the athlete master the “Kote from below” strike as an opposing technique.

(2) Simultaneously, the coach focused on enhancing the athlete's proficiency in “Men.” As a result, opponents increasingly reacted to her “Men” strikes, creating more opportunities for executing “Kote” attacks. As a result, the “Kote from below” technique surpassed the athlete's excellent “Men” as her signature Waza.

(3) During actual training, the coach engaged in “one-on-one practice” with the athlete, confronting her directly. Through immediate assessment of her weaknesses, the coach created simulated situations to facilitate the acquisition of techniques.

(4) Beyond technical instruction, the coach encouraged the athlete to think independently about what actions to take in daily life, regular training, practice matches, and official competitions. This approach aimed to cultivate her “awareness ability.”