The purpose of this study is to report on the author’s mountaineering activities for the past seven years and the changes in his physical preparation for mountaineering, taking running into account, in order to obtain hints for pre-training for mountaineering in the 3000 m class. The author was the only subject, and points were calculated based on the distance, speed, and climbed and descended distance measured by a wristwatch with GPS. The results showed that the daily climbing frequency was 1.4 times/month and climbed and descended distance was 850 m/month, which was considered insufficient to reach high mountains even when the points from running were added. On the other hand, during the preparatory period for alpine mountaineering, the climbing distance was 1294 m/month, which was insufficient, but when running points were added, 6129 points were reached in two months, which was the set point. In the subsequent traverse of a 3,000-meter-high mountain, they were able to traverse the mountain without trouble and with only minor fatigue. Based on the above, in the author’s case, it was thought that about two months of preparatory training activities with an awareness of point acquisition would be sufficient to physically prepare the author for a trip to the high mountains. In addition, it was thought that utilizing a point system proposal that combines mountain climbing and running would make it easier for those who are unable to climb a mountain sufficiently in advance due to geographical problems or difficulty in securing time to do so, to assess their own physical preparedness.

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This study aimed to clarify the characteristics of Japanese athletes by analyzing the techniques and tactics observed at the 18th All Japan Taekwondo Championships (East Japan Regional Competition) and the 18th All Japan Student Championships. The findings revealed that athletes tend to favor techniques that are relatively easy to execute and have high success rates, such as front kicks and side kicks. In contrast, although high-difficulty techniques are used less frequently, they have demonstrated significant scoring potential, indicating their strategic value in competitive settings. Defensive tactics were shown to be highly efficient for scoring, with counterattacking tactics also proving effective in specific scenarios. Moreover, athletes who achieved victory demonstrated superior continuity in their techniques, but a lack of striking power was highlighted as an area for improvement. It was also noted that mid-level techniques were frequently used but had a relatively low success rate. In contrast, highlevel techniques, particularly the downward heel kick, demonstrated notable scoring effectiveness, suggesting a potential tactical advantage. Based on these observations, this study suggests that enhancing the use of highdifficulty techniques and defensive tactics, along with improving technique continuity and striking power, should be emphasized in future training.

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This study examined the effects of squat training on throwing performance in collegiate track and field athletes. After one year of pre-designed squat training, using RIR (Repetitions in Reserve) to determine training load, squat one repetition maximum and throwing distance increased. Body weight also increased, while vertical jump height maintained. In result, training using RIR is potentially effective to increase squat one repetition maximum, which leads to improvement in throwing performance.

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The authors had the opportunity to conduct judo coaching for Pakistani judoka during Ramadan, and this report is intended to assist in future judo coaching. It was considered necessary for the coaches to pay attention to the loss of concentration due to Ramadan, and to improve the content of practice in relation to the normal practice period. Pakistan is considered a country where judo is still in its infancy, and due to a lack of on-site instructors, it was observed that basic judo instruction was not sufficiently provided, so instruction in etiquette and ukemi was provided from the background of judo. In addition, the lack of tatami mats and other judo equipment meant that the practice took place in an environment with a high risk of trauma. Therefore, I provided safety instruction to prevent trauma. During the technical instruction, participants asked many questions about kumite and technique skills, showing their willingness to incorporate Japanese techniques. We conclude our report with the hope that the environment will be improved and that Pakistani judo will be promoted with an eagerness to learn techniques.

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The purpose of this study was to clarify the characteristics of sprint kinematics of the support leg for a wide range of participants, from novices to athletes, by reviewing previous articles analyzing sprint kinematics of the support leg in sprint events. Using three domestic and international search engines, we collected Japanese and English articles analyzing the sprint kinematics of the support leg during the maximal velocity phase of sprint events for both novices and athletes, and summarized the mean values of hip and knee angles and the results of intergroup comparisons. The main results are as follows. The hip angle at touchdown tended to be larger for athlete groups than for novice groups. The minimum knee joint angle of the support leg was larger in novices with higher sprint velocity, and novice groups with high sprint velocity showed values similar to that of athlete groups with low sprint velocity. The knee joint angle at takeoff was larger in novice groups with higher sprint velocity, and smaller in athlete groups with higher sprint velocity. The knee flexion angular displacement in the first half of the support leg was similar to that of world-class athletes for novices with high sprint velocity.

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This study explored the frequency and tendencies of tactical behaviors exhibited during judo matches in order to contribute to the improvement of sports performance in judo. All matches from the All Japan Weight Breaking Championship 2024 were analyzed. Based on previous studies and discussions with co-researchers, nine behaviors in two phases were set as the analytical framework. The results showed that “engaging” was the most frequent behavior with 278 occurrences (31.4%) when the athletes were not grappling. After grappling, “breaking /releasing grip” was the most frequent with 394 occurrences (41.6%). When analyzed by gender, “repelling,” “shifting sleeve,” and “breaking /releasing grip” were significantly more frequent in males, while “engaging,” “avoiding,” and “pushing/holding” were significantly more frequent in females. Comparisons between weight classes revealed that lighter weight classes exhibited more behaviors aimed at maintaining distance from the opponent, while heavier weight classes exhibited more behaviors aimed at gaining a superior position after grappling. Through this study, we were able to clarify the characteristics of tactical behaviors during matches. Additionally, we were able to identify the similarities and differences in performance structures between genders and weight classes.

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Currently， there are several high school dance clubs in Kagoshima Prefecture that are engaged in creative dance，and many schools are seen incorporating elements of classical　ballet， contemporary dance， and modern dance into their works． However， in the prefecture as a whole， due to factors such as the fact that many students have only a few years of dance experience，few students have mastered the basic physical techniques incorporates more advanced movements， including the physical skills of classical ballet， contemporary dance， and modern dance． Therefore，we thought that it was necessary to improve the basic techniques to perform creative dance for high school dance clubs in Kagoshima． The author created six combinations of five types and put them into practice in one high school dance club in Kagoshima． After two weeks of continuous practice， there was some improvement in movement in each combination，but many issues remain before the students could fully achieve the goals we had set．Judging from results of the survey about those combinations and practice，we reexamined the content of each combination and improved them into five combinations of five types． As a next step，we would like to examine the results and challenges of the combinations created in this research more scientifically by using objective indicators and conducting long-term follow-up observations， and consider better practice methods．

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It may be because of the influence of the mentor-apprentice system that information has never been widely disclosed nor any actual survey has been conducted on modern and contemporary dance studios. This study aims to collect such information using an Internet search site, which is a highly disclosed tool accessible to learners, to show the fact of modern and contemporary dance studios, the characteristics of their dance instructors and recognition of qualifications. A total of 403 people were surveyed using mail and Internet surveys, yielding data from 87 respondents (21.6% response rate). As a result, Dance studios established in the 1980s and 1990s accounted for 22–25% of the total number of studios, with an average of 59.63 students per class, ranging from 2-86 years old. The age of the instructors was 52.45 ± 15.88 years old. That were diverse in the names of the classes they taught, the dance genres in which they had experience, and the qualifications they held, which were not limited to modern dance. As for their careers, 65.33% of instructors had experience of being affiliated with a dance company and 51.81% had experience of being affiliated with a dance school. However, the instructors themselves were not certain whether they could evaluate their teaching skills based on these statistics. Still, currently, Students in a dance studio may be evaluating instructors based on information like company affiliation experience, so, the need to clarify the relationship between which careers are associated with which dance teaching skills was confirmed. It was found that they skeptical about the requirement to hold qualifications.

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The purpose of this study was to use stats to statistically examine which team has the “unique tactical style” and which team has the “flexible ability to change tactics based on the characteristics of their opponents” during a season in the W-League as well as which style is more effective, based on the team’s competitive performance. Subjects were the 14 teams that were in the W-League during the 2022-23 season. The game stats used were the seven items referred to as the “Four Factors”. Since the seven items were obtained for offense (own team) and defense (opposing team), a total of 14 items were eventually used. Correspondence analysis was performed on the mean-stats matrix of each team by the game to visually identify the characteristics of the teams. The characteristics of each team’s configuration were operationally defined in terms of “Uniqueness” and “Prominence.” Then, through the interpreted names of its axes, the changes in each team’s game-by-game were examined in terms of the positional relationships of the two-dimensional configuration. As a result, the following findings were obtained: The offensive team types were characterized by “3Ps,” “2Ps,” “Passive offense,” and “Aggressive offense,” while the defensive ones were characterized by “3Ps,” “2Ps,” “Successful defense,” and “Get a free throw.”In league games, which are played by analyzing opponents in advance and with adequate preparation, the superiority of the playing style according to the opponent was demonstrated.

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The purpose of the study was to examine the relationship between performance in the tackle situation in rugby union and the factors that make a play successful, and to gain useful insights for non-top-level through a comparison of the world top level and the university level in Japan. The main results of this study were as follows; 1）Tackling the upper body is highly effective. 2）For the non-top level, improving tackle ratios to the upper body is important, but improving accuracy in tackling the upper and lower body is a challenge. 3）The tackle assist is highly effective. 4）The ratio of tackle assists occurring at the university level in Japan is higher than at the world top level. 5）For the non-top level, improving the accuracy of tackle assists is a challenge. 6）It is important to aim for tackles to the lower body while generating as much tackle assist as possible. 7）The rush defence is highly effective. 8）For the non-top level, creating the enough time to rebuild of defence line is a challenge.

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The present study investigated the factors influencing the success or failure of reception attacks from the left side in volleyball games played in the Women’s V-League, with a focus on categorizing offensive situations into In-System (hereafter called IS) and Out-of-System (hereafter called OoS) scenarios. The results revealed that, in both IS and OoS conditions, the intensity of the attack was the most significant factor influencing the outcome. Additionally, in IS situations, the number of blockers was found to be a critical factor, whereas in OoS situations, the type of set and the attack location were identified as key contributors to the success of reception attacks. A detailed analysis of category-specific contributions, as indicated by category scores, showed that in both IS and OoS conditions, soft attacks had negative values (IS: -1.951, OoS: -1.192), suggesting that in any offensive situation, the goal should be to execute a strong attack. However, even when a strong attack is challenging, it is crucial to return the ball in a way that hinders the opposing team’s offensive capabilities and allows one’s own team to maintain an advantageous position in the subsequent rally. Furthermore, in IS conditions, reducing the number of blockers contributed to successful outcomes, while in OoS conditions, using overhand sets and attacking from slots 1 and 2 were significant factors in determining the success of the play.

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The present study aimed to examine the positional relationship and verbal communication between two baseball outfielders for deciding who will catch a ball hit between players. The participants were eight collegiate baseball players (4 center fielders and 4 right fielders). The present study was conducted in an actual baseball field, a knocker hit a grounder or fly ball between the center and the right fielders, and the participants were asked to judge which player (center or right fielder) should catch the ball and then one of them actually caught the ball. As results, when the distance from the bat-ball impact point to the catching position was long (2 meters or more in this study), the decisions about which player was responsible for catching the ball depended on the positional relationship of the players and the direction of the ball. Mainly, the player who had the shorter distance from the position at the bat-ball impact to the catching position caught the ball. Additionally, to communicate, the players will call to each other. Especially, it was frequently observed that after one player declared his intention to catch the ball, the nonball catcher gave instructions to the other player. Furthermore, the timing of the call was changed according to the player’s positional relationship and the direction of the ball. In particular, the call was made at a later timing when the ball was nearly in the middle of the two players.

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To effectively promote training, it is first necessary to explicitly define the structure of the target sports performance, namely, a structural model as a blueprint (JSPO, 2019). The performance in measurable events such as jumping events and sprinting in the track and field can be relatively structured owing to clear indicators such as jump distances and running times. However, in ball sports, it is necessary to capture the performance structure in a hierarchical manner, including tactics, techniques, and physical fitness, and to explain performance using more abstract concepts. In this paper, the author, who holds a higher-level certified sports instructor qualification, attempts to structure game performance in tennis and presents it as an idea. The abstract elements, such as the purpose and structure of tennis, and specific game techniques, such as strategies and tactics, as well as the detailed techniques to achieve those strategies and tactics–in other words, the technical structure of each shot– were outlined, along with their connections and elements. The visualized game performance structure of tennis created by the author could become an important tool for deepening the mutual understanding between players and coaches.

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The aim of this study was to investigate the effects of EPA intake over 6 months on EPA concentration, EPA/AA ratio and 5000 m running performance. The results of 58 male collegiate long-distance runners (5000 m: 14 min 30.6 s. ± 30.0 s.) showed that the group that were administered EPA had higher EPA concentration and EPA/AA ratio than the group that were not administered EPA. In addition, EPA concentration, EPA/AA ratio, and 5000m running performance of the administered EPA group improved from pre to post intake and a case analysis of the athletes who were administered EPA demonstrated that EPA concentration, EPA/AA ratio, and 5000 m running performance improved after EPA intake. These results suggest that EPA intake can increase EPA concentration, EPA/AA ratio, and can be predicted to be safe and good for training, and as a result, improve running performance.

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This study aimed to determine whether a drill alternating between uphill and horizontal running reduced knee flexion on ground contact during running on level ground in long-distance runners. Seven long-distance runners ran on a treadmill at 12 km/h, alternating four times between a 6% incline and a level surface. Before and after this intervention, running videos were captured in the sagittal plane to calculate the coordinates of the hip, knee, and ankle joints, and to determine the knee joint angle. Knee collapse was represented by the amount of knee flexion from ground contact to the position of maximum flexion. As a result, knee collapse was significantly reduced from 21.6 ± 6.0 degrees before the intervention to 18.5 ± 4.6 degrees after the intervention. Additionally, the degree of knee collapse before the intervention was significantly correlated with the relative change after the drill (r = 0.82, p < 0.05) . These findings suggest that alternating between uphill and level running reduces knee joint flexion during level running, with the greatest improvement observed in runners who exhibited greater joint flexion during level running before the drill.

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This study aimed to clarify the differences in walking techniques between skilled and unskilled mountaineers through a speed-controlled stair walking experiment and gain useful knowledge for understanding and mastering walking techniques in mountaineering. The subjects were 2 males: an experienced mountaineer with instructional skills and the other was an unskilled mountaineer with little experience. In the experiment, subjects carried a backpack with 20% of their body weight and were instructed to walk up 11 steps of stairs at an ascent speed of 300 m/h, and their whole-body motions were recorded by a high-speed video camera （60fps） from the side. Kinematic data were calculated using data recorded with a motion capture system. The results are summarized below: 1) The skilled subject had a greater hip extension range compared to the unskilled. In addition, it was confirmed that the skilled one may have efficiently raised the center of gravity by using stretch-shortening cycle movement（SSC） . 2） The skilled subject had a stopping phase that suppressed the body’s center of gravity velocity after the foot of the forward-stepping leg touched the ground. It is considered that the accumulation of fatigue is suppressed, and the subject moves more efficiently by adding a phase of muscle relaxation during walking. 3） The skilled subject showed less plantar flexion of the ankle joint during the foot release of the back support leg. This may suppress the kicking motion that leads to falls in mountaineering and realize a highly stable walking motion. These results suggest that skilled mountaineers may achieve more efficient and stable walking movements than unskilled mountaineers, even when walking up stairs at the same height and speed.

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In order for Japan’s volleyball to develop tactically, it is important to analyze teams on a worldwide level, though it is also vital to look domestically. ‘Attacks’ are considered to have a significant impact on the outcome of a match. Using the V-League (2019-2020 season), which is the top league within Japan, as the subject, I have analyzed the correlation between ‘attacks’ and the outcome of a game. The purpose of this study was to obtain guidelines to create better teams, etc. by subdividing the attack (apart from the situational aspect) and analyzing each data set. The results showed that using the Middle on a good pass, its kill percentage and error percentage, as well as the right-side player, known as the Opposite, has a significant impact on the result of a game. The team that uses their middle effectively on a good pass and has an opposite that can put the ball away even on a broken play wins. This study was very meaningful as it clarified the structure of volleyball within Japan. Most of the foreign athletes within the V-League are Opposites, and it is reasonable to state that the foreign athlete’s ability determines the outcome of a team. Based on this research, it is necessary to come up with a structure that not only wins games domestically, but on an international level as well.

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This study aimed to examine the impact of icing the forearm muscle groups of judo athletes on their grip time if holding onto their opponent’s judogi during kumite (grappling). The participants were seven female university judo athletes (age: 20.0 ± 1.2 years, competitive experience: 12.3 ± 2.5 years). They performed an exercise to induce forearm muscle fatigue, followed by a simulated judo match with rules for visually impaired athletes and a 5-min rest period in between. The study compared the gripping time from “hajime” (start) to “mate” (halt) if a hikite (sleeve grip) was broken and the number of times a hikite was broken between two conditions: immersing the forearm muscles in an ice bath during the rest period and resting exclusively in a seated position. The results showed that judogi gripping time was significantly longer in the icing condition than in the resting condition (icing: 18.8 ± 6.2 sec, resting: 13.9 ± 3.9 sec), with fewer grip breaks (icing: 11.0 ± 2.6 times, resting: 16.0 ± 5.4 times). These findings suggest that icing the forearm muscles during rest may improve recovery from fatigue and prevent decreased grip endurance during matches.

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Many of the research findings and instructional books on artistic gymnastics turning techniques are already more than 30 years old. The rules and techniques are very different today than they were 30 years ago, and the techniques and how to do it have changed accordingly. Therefore，this study aimed to clarify the practical knowledge about kinesthesia of the 3 turns in tuck stand on one leg on balance beam for skilled player. The subject was an athlete representing Japan in the 2021 Tokyo Olympics, and two interviewers conducted the interview survey. The results of the interview revealed the structure of the subject’s sense of movement in this turn, and it was inferred that the swinging arm movement determines the success or failure of the technique. It was found that the subject swung his arms less than maximum to keep the axis intact and compensated for the creation of rotational force by swinging his floating legs.

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