The purpose of this study was to clarify the effects of inactivity caused by the novel coronavirus on athletic performance of participants in the Hyogo Junior Sports Academy (HJSA), a sports talent search program in Hyogo Prefecture. The subjects were 6th graders who were selected by the selection committee and participated in the physical development and training program. Three years (2016, 2017, and 2018) were considered pre-coronal, and two years (2020 and 2022) were considered under coronal influence. In 2016, 13 boys and 14 girls; in 2017, 13 boys and 15 girls; in 2018, 8 boys and 13 girls; in 2020, 10 boys and 11 girls; and in 2022, 13 boys and 11 girls. The measurement item performs two items of height and weight about a build. Motor ability was defined as 20-m run, T- run, 4-way reaction (4RE), 10-second stepping (ST), vertical jump, continuous rebound jump (RJ index), and drop jump (DJ index). The results showed no significant differences in height and weight between the pre- and post-Corona periods for either sex. A significant decrease in motor ability was observed in both men and women in the T-run. In addition, significant reductions were observed in 4RE in boys and in 20 m running in girls, indicating that the novel coronavirus disaster had an effect on motor ability.

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There is nothing wrong with a sports organization like a sport club aiming to win. However, in recent years, burnout and many other psychological issues have started happening more frequently in the world of sports due to a too strong emphasis on winning and the pressure it creates. This study aimed to investigate the psychological challenges of a rugby team at University using Diagnostic Inventory of Psychological Competitive Ability for Athletes (DIPCA.3). In this study, DIPCA.3 was used on 68 members of a rugby club at university A to clarify psychological issues among the athletes. Furthermore, I also discussed improvement measures. A multivariate analysis of variance (MANOVA) using grade and squad as independent variables revealed significant differences in the multiple comparison test between these factors. Subsequent univariate analysis of variance (ANOVA) indicated that a significant difference was observed solely in the main effect of grade concerning confidence. Multiple comparisons found that significant difference was observed between years 1 and 3, with the score decreasing each year. Moreover, the results of an exploratory factor analysis led to name the first factor as the “decisive factor” and the second as the “mental power factor.” Furthermore, the results of a two-factor ANOVA using factor score as the dependent variable revealed a significant tendency in the main effects of squad for the “decisive factor,” with the top team having a higher score. A potentially effective improvement plan would be to increase the number of games for the bottom team, which comprised more than half of the third-year students with low confidence scores, with the aim of allowing them to accumulate more experience of success. Moreover, this study also discussed the possibility of improving the decisive factor through games.

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When attempting to acquire sports skills, temporary performance declines or difficulties in learning may arise. This study aimed to investigate, from both biomechanical and psychological perspectives, the effectiveness of learning the short serve in volleyball through the application of “Comparative Practice”, specifically by alternating short and long serves, conducted four times with two university volleyball players (A and B). The biomechanical aspect focused on movement adjustments, with A working on “twisting (right rotation of the trunk relative to the pelvis)” and B on “leaning back (extension of the trunk relative to the pelvis)” before and after the experiment (1 week later) and during retention (3 weeks later). Results showed noticeable changes in movement from before the experiment to after and during retention. From a psychological perspective, there was an improvement in the “evaluation and reflection” aspect of the sports version of the self-regulated learning scale. Insights from reflective comments revealed that incorporating “Comparative Practice” enhanced distinctions in hitting locations and force adjustments. Furthermore, considering reflective comments anticipating real game scenarios, “Comparative Practice” suggests potential applications as a learning method tailored for practical scenarios.

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This study interviewed a college women’s volleyball coach (the author), who excelled at block out of the sideline to score a point. The interview was based on the research question, “How do left players make situational judgments and choose to block out in the period between preparing to receive and spiking the ball?” The aim was to partially elucidate the subject’s movement-based practical knowledge. The results are as follows. When preparing to receive the ball, the subject tended to selectively pay attention to subjective elements including the game situation up to that point and the tendencies of the opposing blocker. Meanwhile, when checking the quality of a toss, the subject tended to selectively pay attention to objective elements like “herself and the opposing team,” “herself and her own team,” and “herself, the net, and the position of the ball.” The information collected while reviewing the quality of the toss was an important factor in deciding whether to block out. Particularly, she would determine whether the toss reached the vicinity of the antenna and whether the ball was between the net and herself before deciding whether to block out.

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In scenes of coaching practices, a variety of coaching terms are used by coaches and performers. The key word of the current study “waiting” and the words which involve “waiting” are often employed as coaching terminologies. On the other hand, it is considered that there are occasions where the actual meaning of these words is not truly shared or effectively communicated between speakers and listeners. The current study is a case study of phenomenon “waiting” and analyzed the meaning and fact of this phenomenon from phenomenological movement theory point of view. When a particular movement occurs too early, there are occasions where the timing could not be fixed by “waiting” or “holding”. For example, there are situations where “waiting” itself is technically not possible. Moreover, there are situations where “waiting” is not technically difficult but performing such technique at correct timing is difficult and could lead to a dangerous failure. In the current study, it is found that occurrence of knack is essential to perform “waiting” at the correct position and timing to solve such problems.

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In competitive sports, measurements and evaluations are conducted to quantify and standardize the physical abilities and aptitudes of players and events that occur in various situations. Based on these evaluations, the entire team and individual athletes strengthened. This study aimed to apply an evaluation of daily awareness and behavior toward competition to team analysis, problem-solving, and coaching using the “Condition Management Model” for self-conditioning of athletes. In this study, we used a matrix sheet created based on the average values of three subindices (reinforcement, recovery, and self-analysis) to evaluate condition management and classified the responses into four categories. As a result, issues, problems, and targets of guidance for the entire team that had previously been latent became clear in the case studies, and the quantification of these issues made it possible to reevaluate them and confirm their usefulness for team guidance regarding daily awareness and behavior toward competition.

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The purpose of this study was to investigate the relationships between CHU-Test performance and the number of high-intensity accelerations or decelerations performed during soccer matches. The participants consisted of 16 male university soccer players, who were 19.3 ± 0.9 years, attaching GPS devices during both CHU-Test and soccer matches. The number of high-intensity accelerations ( ≥ 3 m/s²) and decelerations ( ≤ -3 m/s²) was determined from GPS data during both CHU-Test and soccer matches. The CHU-Test performance was 17.9 ± 3.1 times. The number of high-intensity accelerations during soccer matches was 51.6 ± 16.0 times, while the number of high-intensity decelerations was 41.0 ± 12.0 times. Significant correlations were observed between CHU-Test performance and the number of high-intensity accelerations during full-time soccer matches (r=0.83) as well as the number of high-intensity decelerations (r=0.65) (p<0.05). Furthermore, CHU-Test performance showed significant correlations with the number of high-intensity accelerations (r=0.74) and decelerations (r=0.52) during the peak 5-minute period and with the number of high-intensity accelerations during the last 15-minute period of matches (r=0.82) (p<0.05). These results indicate that CHU-Test performance reflects the number of high-intensity accelerations and decelerations performed during soccer matches.

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This study aimed to comparatively assess baseball players and sprinters in terms of the movements of the torso and the characteristics of step variables and pelvic elevation while running on a treadmill. Ten college baseball players and ten sprinters ran at 8.0 m/s in a motorized treadmill. Three-dimensional motion analysis was performed to compare the height of center of mass, step variables, and torso segment kinematics. The height of center of mass during the swing phase was significantly lower, and the step frequency was significantly higher in baseball players, suggesting that the baseball players have greater advantage for the change of direction with deceleration and acceleration. However, the stance time was significantly longer, and the torso rotation angle at initial ground contact and the displacement of torso rotation were significantly greater in baseball players than in sprinters. These factors may not allow baseball players to achieve running speed compared to the sprinters and lead to the development of training methods for baseball players to improve running speed.

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This study examined the effectiveness of tactical training and its coaching in soccer as a case study. In soccer, players are required to employ precise technique while making accurate judgments in changeable situations within the limitations of time and space, particularly in the interplay between defense and offense. Despite the significance of these abilities, limited research has been conducted in this area. We implemented defense training based on a team concept for three months. Our hypothesis posited that team performance could be improved when each member understands and accomplishes shared team tactics. The defense training in this study utilized mutually built keywords to enhance a common understanding within the team and checked levels of understanding to confirm individual comprehension. Subsequently, the effectiveness was examined through game analysis and comprehension test results. The game analysis suggested the effectiveness of defense tactics as part of the team concept. Furthermore, the timing of increased points won in games coincided with the timing of comprehension test confirmation, indicating that the improvement in the team’s understanding of defense stemmed from a deepened grasp of individual team tactics and improved situational judgment.

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This study aimed to establish a methodology for recording and analyzing routine compositions in rhythmic gymnastics group exercise. We developed a recording sheet based on previous research. In collaboration with two international judges, we documented the routine composition of a performance that achieved first place in both difficulty and artistic score in the Hoop5 event of the 39th FIG Rhythmic Gymnastics World Championships. We visualized the recorded content and confirmed a 96．8% agreement among the three judges. Furthermore, triangulation was conducted with two additional recorders, excluding the author, that validated the reliability and applicability of the method for recording and analyzing routine compositions by international judges.

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This study aimed to examine the variation of environmental temperature in a gymnasium without air conditioning from July to September 2023, and heat stroke by college female basketball in a gymnasium without air conditioning from June to September 2023. Monthly temperatures and WBGT showed no change at high levels from late July to mid-August and began to decline in late August. Conversely, humidity increased from late July to mid-September and decreased in late September. In addition, it is considered that gymnasiums without airconditioning equipment are environments with a high risk of heat stroke because maximum temperatures from late July to mid-September exceeded the level for exercise stops. The number of Heat Stroke cases by position was 17 for guards, 11 for forwards, and 2 in centers, and it was suggested that position may be related to the occurrence of heat stroke. Basketball is a sport with a high risk of heat stroke, and there is a limit to preventing heat stroke by fluid intake because there is no timing for fluid intake during the game. Therefore, in environments where airconditioning equipment is not available, it is necessary to design practice plans flexibly and strictly prepare for the heat.

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In baseball hitting, it is very important to catch the ball accurately with the sweet spot of the bat, but training methods to improve hitting accuracy are unknown. The purpose of this study was to clarify the effect of hitting practice with a bat painted at the sweet spot on the accuracy of baseball hitting. Male college baseball players were divided into 8 training group (Tr) and 8 control group (Con). The Tr used bats with painted at the sweet spot, and the Con used bats without painted at the sweet spot. Both groups trained three times a week for a total of 12 sessions of 20 balls × 2 sets over a 4-week period. Hitting measurements were taken before and after training using an optical 3D motion analysis system. From the data obtained, the impact position (accuracy of hitting), swing velocity, and exit velocity were analyzed. The results showed that the Tr significantly improved in hitting accuracy and swing velocity. On the other hand, only exit velocity was significantly improved in the Con. These results suggest that hitting practice with a bat painted at the sweet spot improves hitting accuracy and swing velocity more than hitting practice using a normal bat.

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Goalball is considered to possess values and characteristics that can foster awareness of new bodily knowledge. However, there is inadequate investigation into whether this new bodily awareness is reflected in actual performance changes. Also, for novices, mastering goalball throwing skills is challenging, requiring progressive exercises and corresponding instructional materials. This research concentrates on the throwing skills in goalball and aspires to propose teaching materials that can facilitate the awareness of new bodily knowledge during class lessons and improve throwing proficiency. The process entails（ 1） an exploratory pilot study by the authors, and（2） trial implementation with a few participants, on the basis of which the final teaching materials are proposed. The study also aims to present findings obtained from the pilot study and trial implementation that contribute to the enhancement of goalball throwing skills. The results indicated that the developed teaching materials could be adequately utilized with the intent of fostering awareness of new bodily knowledge and enhancing goalball throwing skills. We were also able to identify three cues in bodily knowledge that serve as references for targeting the ball directly ahead. Additionally, we managed to propose refined teaching materials for easier utilization in classes and similar settings. Future directions include the exploration of usage methods for these materials in class settings and research on their practical implementation.

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This study aimed to summarize change in the 400 m record from 2013 years to 2021 years with relation to training strategies for SATO Kentaro who was a member of national men’s 4x400 m relay at the World Championships and the Olympic. He has specialized in the 400 m race since high school, and is the type of sprinter who maintains his running velocity throughout the entire 400 m race. After entering college, the team actively gained running velocity from the first half of the race and focused on efforts to maintain running velocity through the second half, setting a new record of 45.58 s in 2015. After that, he began to compete in the World Championships as a member of the Japanese national team, and although he began to gain more aggressive running velocity in the first half of the race, he lost a lot of velocity in the second half, and his record remained low. Therefore, in 2021, the 400 m race was changed to a race development with an image of rest while obtaining and maintaining high running velocity in the first half of the 400 m race. As a result, signs of record-breaking were seen, and the team was able to participate in the Tokyo Olympics. In this study, we sought to find clues for future record-breaking by summarizing the relationship between efforts and records up to fiscal year 2021.

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This study examines the effects of training using the throwing practice gear FLECHA on throwing performance for a university baseball player who experienced the yips during high school. The training involved performing 20 throws of FLECHA per day, at least 4 times a week, over a period of 3 months. In order to maximize the training effects, the use of regulation balls for throwing was prohibited throughout the 3-month training period. As a result of the training, improvements in the trajectory of the throwing arm, the acquisition of “flexing” movements involving the trunk and upper body, and the resolution of “bending” movements in the stepping leg led to significant improvements in both ball speed (from an average of 98.2 ± 3.0 km/h before training to 119.2± 2.2 km/h after training) and ball spin rate (from an average of 1216.8 ± 80.3 rpm before training to 1484.2 ± 93.6 rpm after training). On the other hand, accuracy decreased temporarily after 3 months of non-throwing balls, but returned to normal soon after returning to normal activities. These results suggest that that the training using FLECHA may improve the throwing performance of college baseball players who experienced the yips in high school.

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This study aimed to investigate the influences of vocalization, specifically “shout”, on the throwing distance with a softball in collegiate male athletes. Ten collegiate male subjects had played baseball and/or softball in the competition level for more than 5 years. To verify the effects of different shouting conditions on throwing distance, participants were instructed to throw a size 3 softball ball under various vocalization conditions, including shouting (using a familiar shout and different vowel sounds: a, i, u, e, o) and no vocalization. All participants completed two throws under each condition in random order. Although no significant differences were observed between vowel sounds and no vocalization, the throwing distance was significantly increased when participants utilized their familiar shout in comparison to conditions with no vocalization and vowel sounds “u” and “e”. All participants experienced the shouting effect, while a few decrease the throwing distance with vowel sounds because they were distracted to shout. These results suggest that voluntary shouting during the throw improved the throwing distance compared to conditions without vocalization. However, when participants were required to shout with a specified vowel sound during the throw, the effects of the shout on throwing distance might not be observed because their attention would be directed toward the vocalization itself.

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The purpose of this study is to describe in detailed examples of the practice process leading up to the implementation of “Cassina” in a competition and exploring effective consciousness. The subject is an athlete who won a silver medal in the gymnastics team final at the Tokyo 2020 Olympic Games. It became clear that practicing with an awareness of the giant in the preparation phase is important to catch the bar in “Cassina”. Especially, in the acceleration phase, it is important to maintain straight body and the toes go through as far as possible. In the preflight phase, it is crucial to arch outwards.

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This study aimed to clarify the characteristics of throwing motion to second base of the professional baseball catcher who has been selected for the Japan national team and has previously recorded the highest stolen base prevention rate in a season. Although the player’s long throw distance （arm strength） was not outstanding as a professional baseball player, his quick movements had been described as leading to a high base-stealing prevention rate. We compared the throwing motion of this catcher to three other professional baseball catchers. An optical three-dimensional motion analysis system and a force plate were used to measure the throwing to second base. The throwing motions were divided into three phases. Duration of each phase, ball speed, and kinematics were then analyzed. The results showed that the catcher selected for the national team took the shortest time from the catching phase to the release phase. In particular, the time required from the time of catching the ball to the time when the pivot foot contacted the ground was shorter than those of the other three catchers. In addition, the catcher selected for the national team showed the highest value of velocity of center of gravity（ CoG） at the time of catching. These results suggest that the catcher selected for the Japan national team shortened the time from the time of catching the ball to the time when their pivot foot contacted the ground by increasing the velocity of CoG even before catching the ball, and that they made a quicker throwing motion to second base by shortening the motion time.

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The present study examined the effects of rotational box jump training on the movement time of the Judo Technique “uchimata” in male university judo players（ n = 18） . The participants were classified into three groups: a rotational box jump training group（ RBJ group, n = 6） , a box jump training group（ BJ group, n = 6） , and a notraining group（ CON group, n = 6） . The RBJ group was instructed to rotate their hips in the same direction when getting on the box as they did when performing the Judo Technique “Uchimura” workout they performed in normal practice, and when descending from the box to the tatami, they were instructed to return using the same direction. For example, if the participants got on the box by rotating their hips to the left, they were instructed to rotate their hips to the right when they got off the box. The training was conducted three days a week three sets of ten times for four weeks, for a total of 12 sessions. As a result, the training of the RBJ group shortened the movement time from the “Kuzushi” to “Tsukuri” phase. Moreover, the rebound jump index was significantly improved. These results suggest that rotational box jump training improved the ability of Stretch-Shortening Cycle （SSC） and shortened the movement time of the Judo Technique “uchimata” in university judo players.

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In this study, I grasped problems of the enforcement that left the horizontal bar distantly targeting at the university student gymnasts that dismounts of the horizontal bar in men’s gymnastics was unripe and was intended that I showed the correction example that solved the problem. The target person was four university student gymnasts whom the writer instructed and performed the enforcement that left it distantly from a horizontal bar. As a result of having let you carry out the exercise method that the writer devised, four target people were able to perform the enforcement that they revised in the game not the enforcement that left it distantly from a horizontal bar. And I was able to show a flow of the correction instruction to become the cause when I instructed it and the point that you should warn in future.

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At present, studies on guides to blind runners（ BR） have reported that their motives for participation are extrinsic, such as recommendations and requests from others. In terms of activities, there are many clubs to which BR and companions belong, and practice sessions are held regularly. We have examined issues in matching with the guides and the BR from the BR side（ Hirai, et.al, 2020）. Therefore, the purpose of this study was to clarify the same problem from the guide side. The research method was to conduct a semi-structured interview with five guides belonging to the A guide runners club, and analyze the obtained audio data by a modified grounded theory approach. As a result, the following four points were clarified. （1） The problem with communication between the guide and the BR was to increase the guide’s efforts and the quantitative aspect. In the previous studies analyzed from the BR side, the qualitative aspect of communication was regarded as a larger problem, and there was a difference from this study. （2） Both sides were required to develop the ability to find a suitable partner, and for that purpose, it was necessary to expand their personal connections. （3） Depend on the matching methods, the challenge was to find a partner with the same running purpose. However, both sides say that it is possible to run together even if the purpose is slightly different. （4） It was important for both sides to stay in touch actively and on a daily basis regarding matching in daily practice. This was a common perception between the guide and the BR.

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This study aimed to examine the psychological characteristics of competitive swimmers during long-term activity restrictions due to coronavirus disease 2019 (COVID-19) and difference in psychological skills between men and women at different competition levels. Participants were selected from 118 competitive swimmers who trained daily before the long period of restraint from activities due to the COVID-19 pandemic. The participants responded to basic attributes, psychological performance self-esteem (SE), diagnostic inventory of psychological competitive ability for athletes (DIPCA.3), and self-trust scale for athletes, and comparisons were made by gender and competitive level. The responses were tabulated and subjected to t-tests and one-way analysis of variance. Results showed that men scored higher in relaxation ability and confidence than women. Entries were classified into three groups: international, national, and local competitions. A comparison between international and local competitions showed significant differences in self-control ability SE, including strategic ability SE and mental stability and concentration, both of which were higher in the international competition group. These results suggest that psychological skills tend to differ between men and women and at different competition levels in terms of sport activity limitation due to COVID-19.

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This study investigated the reliability of measuring the trunk rotation range of motion using an additional installed smartphone application (Angle Meter) and its relationship to thoracolumbar flexibility. Trunk rotation is vital for various activities such as swinging bats or rackets and throwing because it influences the movement of the trunk and upper extremities. The participants were 60 healthy male college students, measuring the active range of trunk rotation in a sitting posture using the Angle Meter to measure the angle of left-right rotation. To evaluate reliability, they looked for significant differences, calculated intraclass correlation coefficients, and assessed systematic errors. Additionally, they used the Angle Meter to measure thoracolumbar lateral flexion on both the sides, as well as flexion and extension in the sit and reach test and prone trunk extension test, respectively. The results indicate that there were no significant differences in the repeated measurements of trunk rotation in the sitting position. The intraclass correlation coefficient was impressive at 0.881, indicating high reliability. No additive or proportional errors were found. Thus, the Angle Meter proves to be a useful tool for measuring the active trunk rotation range in the sitting position. However, the trunk rotation range in the sitting position showed a weak correlation with thoracolumbar flexion and no correlation with lateral flexion or extension. In conclusion, the Angle Meter trunk range of motion test is beneficial; however, it has limited relevance to thoracolumbar flexibility.

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This study compared the joint angles measured during the execution of uchimata (inner thigh throw) among judokas with varying skill levels. It also derived practical insights for technical instruction. The study participants included 20 male judokas belonging to a university judo club, 10 of whom had participated in national tournaments (hereafter referred to as “skilled”) and 10 of whom had not participated in national tournaments (hereafter referred to as “unskilled”) . Movements were recorded using Mac3D (frequency 250 Hz) , an optical 3D movement analysis system. Ground reaction forces acting on the judoka’s feet during the movements were measured using a force plate (frequency 1000 Hz) . The results showed that the skilled group had a greater maximum trunk tilt angle than the unskilled group, and this maximum angle occurred significantly earlier. Additionally, there was a tendency for the maximum value of Tsurite to be smaller, whereas the maximum value of Hikite was larger. This led to skilled judokas effectively pulling the opponent forward and possibly using the principles of leverage for the throw. Therefore, it was suggested that to enhance the uchimata technique, using both Tsurite and Hikite to collapse the uke during the Turning phase would stabilize the posture of the tori during the Throwing phase, even when standing on only one pivot foot, and would enable the tori to quickly lift the opponent.

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The purpose of this study was to clarify the problems of regional collegiate women’s doubles tennis by focusing on the point acquisition and the last shot of a rally. Total number of the subjected matches were thirty and categorized as the world tour, the national collegiate tournament, and the regional collegiate tournament. All the matches were held in hard court and 3-tiebreak sets. We tagged all the matches by SPLYZA Teams (SPLYZA Inc.). We calculated point winning rate by server (receiver), the frequencies of rally numbers, the ratio of the last shot, and the last shot player ratio when the rally finished by net play. As a result, the point winning rate showed high on the 1st serve. Especially, the last shot ratio of the return showed high on the world tour category. The last shot ratio of net play showed low on the regional collegiate tournament. When the rally finished by net play, the ratio of the partner of the server or the receiver showed high on the last shot player ratio. Those results insisted the problems of regional collegiate women’s doubles tennis were the techniques of serve or return and the net-play for the positional role of the partner of doubles team.

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