Taiikugaku kenkyu (Japan Journal of Physical Education, Health and Sport Sciences)
Online ISSN : 1881-7718
Print ISSN : 0484-6710
ISSN-L : 0484-6710
Volume 60 , Issue 2
Showing 1-29 articles out of 29 articles from the selected issue
Original investigations
  • Takuya Ueno, Hideaki Komiya
    2015 Volume 60 Issue 2 Pages 401-414
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 03, 2015
    JOURNALS FREE ACCESS
      In the present four-year longitudinal study we investigated lifestyle factors that would improve the physical fitness of children considered to have “inferior” physical fitness.
      The participants were 9,593 elementary school children. Personal data obtained annually were linked over four years. In the first year, we focused on the group considered to have inferior physical fitness (T-score <45). We calculated the degree of change in terms of differences in T-scores between the first and fourth years. On the basis of the change evident in the fourth year, we subdivided the “inferior” group into two groups: those showing a decrease or increase in physical fitness. We then analyzed the lifestyle changes in the two groups.
      In the group showing increased physical fitness, fitness had improved to the national average after three years. Improvement of exercise habits was show to enhance fitness, whereas deterioration of exercise habits reduced fitness. This difference between the groups was significant. In contrast, health habits and dietary habits showed no significant inter-group differences, and no association with physical fitness.
      These results suggest that improved exercise habits can help attain the national average or even increase the physical fitness of a child who has been previously evaluated to have inferior fitness.
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  • Rie Yamada
    2015 Volume 60 Issue 2 Pages 415-428
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: June 24, 2015
    JOURNALS FREE ACCESS
      The game of dakyugi (literally, “hitting-ball-game”), involving 3 components of play (hitting a ball, throwing a ball, and pushing of opponents), is a traditional stick game that has been passed down to the present in Kuwana City (Mie Prefecture).
      The purposes of this study were to examine the process of the game's revival and cultural features, and to clarify the significance of dakyugi as a traditional sport in regional development through sports. The materials used in this study were mainly collected through fieldwork at the Rikkyo Area Great Meeting and interviews with members of the preservation association, as well as investigation of historical sources.
      In the Meiji era, dakyugi had been played as a bravery game by boys in the Kuwana gijyuku, which inherited the idea of the Rikkyou-kan, a school in the fiefdom of Kuwana. Although dakyugi declined after World War II, it was revived to mark the 150th anniversary of Matsudaira Sadanobu's death in May 1978.
      Today, dakyugi is performed at the Kuwana Municipal Rikkyo Elementary School supported by the Dakyugi Preservation Association. Boys and girls of the school play the game at the athletic meeting held jointly by the school and Rikkyo area community. The game of dakyugi in Kuwana is noteworthy in promoting the behavior pattern and style of samurai culture that characterized the Edo era. In addition, dakyugi is considered to play an important role in the revitalization of provincial cities and in the establishment of local regional identity.
      The significance of traditional Japanese culture is emphasized in the present school education program. The current study indicates that traditional Japanese sport culture can play an important role in regional development in Japan.
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  • Keiko Itani
    2015 Volume 60 Issue 2 Pages 429-448
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: June 12, 2015
    JOURNALS FREE ACCESS
      In 2002, the Central Education Council published a report entitled “Improvement of children's physical fitness”. The report pointed out that changes in the social environment and lifestyles in recent years had influenced children's physical fitness and movement skills, and that a “comprehensive policy” addressing various aspects was essential for tackling this problem. On the basis of this report, the Ministry of Education and local boards of education are currently undertaking various projects; however, a number of gaps still remain between the findings of the report and what is actually being done to address this issue.
      The present paper examines the local political issues that have led to differences between the practices of local educational governments and the recommendations of the report by focusing on practices in the Tokyo Metropolitan area and Osaka Prefecture after publication of the report.
      This study revealed that the local governments had been strongly influenced by the results of physical fitness tests in comparison with other districts, counter to the comprehensive policy suggested by the report. This suggests that one of the reasons for the existing gap is the implicit demand for measurable results based on strong promotion of the evaluation system stipulated by the current educational policy. The results also show that most projects to improve children's physical fitness have been undertaken by schools, despite the fact that almost no budget has been allocated for this purpose, thus forcing schools to bear the burden and responsibility alone. Furthermore, it is also evident that competitive sports are frequently used to promote an active lifestyle, even in elementary and junior high schools.
      In view of the numerous practices aiming to improve performance through sports club activities and competitive sports events, such as long-distance relays for children and Olympic education, it appears that the government in fact has a hidden agenda to promote sports and to improve athletic performance behind the façade of children's fitness as a “social issue”.
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  • Yuta Ono, Hidenori Tomozoe
    2015 Volume 60 Issue 2 Pages 449-465
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 14, 2015
    JOURNALS FREE ACCESS
      The Young Men's Association (YMA) was an education institute that provided programs and further education for young men. It aimed to train both mind and body, and valued physical education.
      However, in preceding studies of the YMA, emphasis was placed on the national stance that physical education should be promoted, or the implementation status of physical education in the YMA in the local community. Insufficient consideration was given to the policy and process of local government liaison between the national aim and regional implementation. The aim of the present study was to clarify the process of development of the physical education promotion policy of the YMA, taking as an example the Tokyo Prefecture administration during the Taisho Era.
      The following points were clarified:
    1)  At the Local Governor Conference, no instruction was given regarding any specific method for development of physical education promotion by the YMA. Therefore, in each prefectural administration, policies needed to be formulated and implemented, taking into account the regional situation within each individual jurisdiction.
    2)  Prefectural Governor Tomoichi Inoue, who spearheaded the YMA policy in Tokyo Prefecture, had set as the main objective of the YMA, the implementation of civil education and labor education for working young men. He considered physical education to be “prerequisite for all” activities of the YMA. In so doing, the aim was to train “young men who contribute to labor” through physical education.
    3)  As a specialized institution reviewing physical education policies of the YMA in Tokyo Prefecture, Governor Inoue established the “Tokyo Prefecture Physical Education Council”. The council members consisted of not only Tokyo prefectural workers, but also external “education and physical education experts”.
    4)  The Physical Education Council raised as specific issues, “improvement of the physique and strength of young men” and “popularization methods for physical education”, and held repeated discussions with these aims in mind. In resolving the above issues, the Physical Education Council cooperated and collaborated with companies within Tokyo Prefecture, and further held “workshops” and “lectures” at the YMA at local level.
    5)  The Physical Education Council compiled the information obtained through discussions and through such “workshops” and “lectures”, and therefrom established and issued the “Tokyo Prefecture Regulations for Young Men's Physical Education”. Promotion of these regulations played an important role in the origin of YMA physical education in Tokyo Prefecture in the years that followed.
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  • Yasuo Susaki, Yoshio Sugiyama
    2015 Volume 60 Issue 2 Pages 467-478
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 09, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to examine relationships among adjustment to school, adjustment to physical education classes, and a self-regulated learning strategy in physical education classes. The participants were 420 university students (male=248, female=172, mean age=18.70 yr, SD=1.23 yr), who completed a questionnaire assessing their adjustment to school, adjustment to physical education classes, and a self-regulated learning strategy for physical education classes. The researchers implemented a hypothetical model by utilizing structural covariance analysis. The results were as follows: (1) The hypothetical model showed acceptable fit indices (GFI=.94, CFI=.95, RMSEA=.079); (2) a self-regulated strategy had a positive effect on intention of solidarity (β=.31, p<.01) and adjustment to physical education classes (β=.58, p<.01); (3) intention of solidarity had a positive effect on sense of comfort (β=.43, p<.01), existence of task and purpose (β=.29, p<.01), and absence of feelings of inferiority (β=.20, p<.01); (4) adjustment to physical education classes had a positive effect on sense of comfort (β=.34, p<.01), existence of task and purpose (β=.39, p<.01), feelings of acceptance and trust (β=.33, p<.01), and absence of feelings of inferiority (β=.15, p<.01). These results suggest that a self-regulated learning strategy is connected to adjustment to physical education classes, with the latter leading to enhanced adjustment to school.
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  • Terumi Tanaka, Yoshio Sugiyama
    2015 Volume 60 Issue 2 Pages 479-488
    Published: 2015
    Released: December 18, 2015
    JOURNALS FREE ACCESS
      In this study, we confirmed whether positive affect have improvement effect on the burnout tendency through problem-focused coping in university student athletes. The participants were 206 male members from university athletic clubs. Firstly, based on previous studies, we established a hypothetical model using positive affect as an independent variable, problem-focused coping as a mediator, and burnout tendency as a dependent variable. Positive affect was evaluated by the PANAS Japanese version, problem-focused coping was evaluated by the Situational version of the General Coping Questionnaire, and burnout tendency was evaluated by the Athletic Burnout Inventory scale. Secondly, we used covariance structure analysis to examine the validity of this hypothetical model. Finally, we estimated whether positive affect have improvement effect on the burnout tendency. Results showed that 1) each of the fitness indices in the hypothetical model showed higher values (GFI=.975, AGFI=.923, CFI=.984, RMSEA=.074) which satisfied the adoption standard, thus demonstrating the validity of the hypothetical model, and that 2) positive affect was confirmed to have improvement effect both directly and indirectly on the burnout tendency.
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  • Mitsuharu Omine
    2015 Volume 60 Issue 2 Pages 489-495
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 29, 2015
    JOURNALS FREE ACCESS
      This study investigated trash talk among soccer players, focusing on whether it actually disturbed playing performance and whether the ability to ignore such trash talk was an asset to the game. The “Laws of the Game” of soccer stipulate that any player who uses “offensive, insulting or abusive language and/or gestures” should be dismissed from the field. Therefore, any penalty imposed on players for such behavior can be interpreted as sanctions for prohibited act.
      Furthermore, any game in which offensive or insulting remark are used was considered by reference to Kawatani's opinion about excellence and “failed athletic contest”. When a referee penalizes a player appropriately for such behavior, it is suggested that the game has not “failed”. On the other hand, as such behavior is often difficult for a referee to notice, an appropriate penalty is sometimes not administered. Therefore, it is suggested that an offensive or insulting remark is an act that indirectly destroys the ethos of a game. I conclude that the ability to ignore trash talk is not an asset to the game in principle, but that such ability is practically necessary.
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  • Sakie Nobuoka, Takatoshi Higuchi, Hiroki Nakata, Tetsuya Ogawa, Kouki ...
    2015 Volume 60 Issue 2 Pages 497-510
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 11, 2015
    JOURNALS FREE ACCESS
      The aim of this study was to clarify the relationship between maximal running speed, step frequency, step frequency index, step length, step length index, foot contact time, and aerial time during sprinting in elementary school children. The participants were 335 girls and 352 boys (age: 6 to 12 years) who ran a 50-m sprint race as part of their school fitness test in 2013. Their maximal running speed, step frequency, and step length were calculated from images captured by video cameras (60 frames/second) located at the sides of the lanes. Contact time and aerial time over the distance from 20 m to 30 m were calculated from images captured by high-speed video cameras (300 frames/second) located at the side of the 25-m mark for the lanes. Two-way ANOVA with the Games-Howell procedure was used to test differences among all grades. Two-way ANCOVA was used to test interaction and the main effect of gender and grade on maximal running speed. The Pearson product-moment correlation coefficient (r) and partial correlation coefficient (pr) were calculated to analyze the relationship between maximal running speed, step frequency, stride length, foot contact time, and aerial time. Step length (which was strongly correlated with maximal running speed) showed a strong partial correlation (controlled for age) with maximal running speed. Therefore, it is suggested that step length contributes to not only the increase in running speed with growth, but also individual differences in running speed among the children at the same age. There were slight tendencies for step frequency and foot contact time to increase with growth. However, these factors showed a significant partial correlation (controlled for age) with running speed. Therefore, it was suggested that these factors contribute to individual differences in running speed. The absence of a negative impact of a shorter foot contact time on stride length suggests that the running performance of school children could be improved by decreasing their foot contact time. In order to establish effective methods for augmenting the development of running ability in children, it will be necessary to consider foot contact time and aerial time in addition to step frequency and step length.
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  • Satoshi Yoshino, Toshihiro Kato, Akane Shinoda, Takuma Saito, Shunsuke ...
    2015 Volume 60 Issue 2 Pages 511-525
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: September 29, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to examine the various categories of games and the similarities of behavior in each category, based on data analysis of university students' self-evaluation of selected games. Data were collected by questionnaire and interview. The questionnaire was administered to 239 (111 male and 128 female) students and asked about their overall evaluation of each selected game, whereas the interview was conducted with 17 (7 male and 10 female) students to ascertain the reasons why they thought they would be suited to the selected games. Cluster analysis was conducted on the questionnaire data to clarify the game classification quantitatively, and qualitative analysis was conducted on the interview data to clarify the similarities of behavior in each game category. The results reconfirmed that the invasion, net, and striking/fielding categories of games were classified similarly to those in several previous studies. In addition, several similarities of behavior in the game categories were revealed.
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  • Yoichi Ohta, Hiroki Nakamoto
    2015 Volume 60 Issue 2 Pages 527-537
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 11, 2015
    JOURNALS FREE ACCESS
      This study aimed to clarify the effects of changing to a short bat grip position from the long bat grip position on baseball bat swing timing, peak ground reaction force with the front leg, and activation of the upper and lower limb muscles.
      Nine male college baseball players participated in this study. By using a batting simulator, the coincident timing task was to swing the bat coincidentally with the arrival timing of a moving target by using the long or short bat grip position. The batter performed 10 sets of 4 swings for a total of 40 swings for the coincident timing task. During the four swings, the batter swung the bat by using the long grip position in the first, second, and fourth swings. Only in the third swing did the batter use the short grip position. The ground reaction force with the front leg was measured, and electromyograms of the upper and lower limb muscles were obtained during the coincident timing task.
      Our results indicated no significant differences in absolute and variable timing errors between the long and short bat grip positions. In contrast, the constant timing error was significantly increased with the short bat grip position. Moreover, the time to peak ground reaction force and time to peak muscle activation of both the upper and lower limb muscles were significantly delayed when the short bat grip position was employed. Significant positive relationships were observed between the constant timing error and time to peak ground reaction force, which showed differences between the second and third swings. No significant difference in swing time was observed between the long and short bat grip positions.
      These findings indicate that changing to the short bat grip position from the long bat grip position will not improve the batter's swing timing. Furthermore, changing to the short bat grip position could delay the batter's swing timing, probably because the change causes a delay in swing preparation.
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  • Kazushige Oshita, Goichi Hagiwara, Takafumi Monma, Tempei Tsuno, Kazus ...
    2015 Volume 60 Issue 2 Pages 539-550
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 25, 2015
    JOURNALS FREE ACCESS
      The aim of the present study was to investigate the effect of experience or inexperience with weight-training under appropriate supervision on knowledge of squatting exercises among university students. A questionnaire-based survey was conducted among university students who exercised regularly (30 or more min per day, 2 or more days per week, and maintaining this for more than 1 year) to clarify the relationships between their experience of weight-training under appropriate supervision, knowledge of squatting exercises, and the frequency with which they perform squatting exercises (n=309). More than half of the students who exercised regularly had never experienced weight-training under appropriate supervision. Approximately 50% of the participants performed squats periodically, even if they did not have any experience with weight-training under appropriate supervision. The participants who lacked experience with weight-training under supervision had made significantly fewer attempts to consciously train their gluteal and knee flexor muscles during squatting exercises than those who had experienced weight-training under supervision. In fact, approximately 50% of the former did not consciously train their gluteal muscles during squatting exercises at all. These results suggest that although the students performed squatting exercises periodically, those who had never experienced weight-training under supervision may not have properly understood the squatting method. Therefore, to enhance the benefits of training, people should be shown the correct method for performing training exercises and given appropriate supervision.
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  • Tomohisa Miyanishi, Naoki Sakurai, So Endo
    2015 Volume 60 Issue 2 Pages 551-564
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 13, 2015
    JOURNALS FREE ACCESS
      The purpose of the present study was to clarify kinematic differences in baseball throwing motions among various types of player positions—pitcher, catcher and infielder—based on kinematic data reported in previous studies. A total of 20 articles including 17 pitching studies, 2 catcher's delivery studies and 1 infielder's delivery study were investigated mainly with regard to trunk and throwing arm kinematics. Since there no kinematic data were available for the trunk and throwing arm of the catcher, only release parameters (i.e., ball speed, release angle, and height of release) and the durations of the 4 throwing phases (i.e., step, stride, arm cocking, and arm acceleration) were compared between the catcher and the players at other positions. The characteristic differences observed for each throwing motion were as follows: Ball speed was greater for the pitcher than for other positions. Although step phase was shorter for the catcher than for the infielder, stride phase was shorter in the latter. Both arm cocking and acceleration phases were shorter for the pitcher than for players at other positions. At the instant of stride foot contact, trunk backward twist and elbow extension angles were larger for the pitcher than for the infielder, and the pelvis backward rotation angle was smaller for the former. At the instant of ball release, the upper trunk forward tilt, upper trunk leftward tilt, and trunk forward twist angles were larger for the pitcher than for the infielder. Maximum elbow flexion and shoulder horizontal abduction angles were larger for the pitcher than for the infielder, whereas the maximum shoulder external rotation angle was smaller for the former. Although there were no marked differences in the maximum upper trunk and pelvis forward rotation angular velocities between the pitcher and the infielder, their times of occurrence arose in the early phase of throwing in the pitcher in comparison with the infielder. These results provide evidence of possible ways in which the throwing performance of players in various positions can be improved.
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  • Yuki Murai, Lee Chanwoo
    2015 Volume 60 Issue 2 Pages 565-575
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 26, 2015
    JOURNALS FREE ACCESS
      The aim of this study was to clarify the background and features of implementation of the Nationwide Swimming Training for Conscription Candidates (NSTCC). The tasks of the study were to elucidate the 1) background, 2) preparation, 3) contents, and 4) results of NSTCC implementation.
      The results of this study were as follows:
      1)  After the outbreak of the Sino-Japanese war, the problem of a lack of swimming ability was observed among soldiers, so municipal governments and the Ministry of Health and Welfare turned to the STCC as the solution.
      2)  As the Sino-Japanese war was prolonged, the Ministry of Health and Welfare integrated the STCC, which had previously been conducted as a separate program, into one implementation throughout the whole country.
      3)  After the outbreak of the Pacific War, the situation was worsening, and the lack of swimming ability in ground forces became obvious. To resolve this problem, the Ministry of Health and Welfare decided on a comprehensive implementation program, which was planned at the beginning of 1943, through the NSTCC.
      4)  The NSTCC was supported by the Imperial Rule Assistance Association and its neighborhood associations. Since swimming training on a nationwide scale was not compulsory for all conscription candidates, the Imperial Rule Assistance Association mobilized conscription candidates to participate in training through different propagandas.
      5)  The National Physical Training Association trained coaches for each prefecture and each implementation district. Most coaches in each implemental district were school teachers.
      6)  In was recommended that the NSTCC be conducted using swimming pools, but a number of implementation districts did so in seas, rivers, or lakes.
      7)  The first half of the NSTCC was intended to cultivate the ability to float, on the assumption that this ability was basic training in order for beginners to master swimming.
      8)  During the second half of the NSTCC, attaining the technique of sidestroke or breaststroke was preferred. Each implementation district was able to choose a stroke (sidestroke or breaststroke).
      9)  Disciplinary training was highly regarded in the NSTCC.
      10)  As 95% of all participants were able to swim for more than 10 meters upon completing training, the NSTCC was judged to have been effective in eliminating a lack of swimming ability.
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  • Takahiko Sato, Toshimasa Yanai
    2015 Volume 60 Issue 2 Pages 577-588
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: October 02, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to determine how runners sprinting along a curved path could rotate their whole-body about the vertical axis to keep facing towards ever-changing movement direction. 10 healthy men were asked to run at 5 m/s along a straight path (RS) and a curved path with a 5-m radius (RC). The running direction in RC was counterclockwise (CCW) as viewed from above. A motion capture system with 8 cameras was used to record the three-dimensional coordinates of reflective markers attached to each subject with the sampling frequency set at 240 Hz. The angular momentum of each body segment about the vertical axis passing through the center of mass of the entire body was determined for 1 complete stride cycle with the method described by Dapena (1978). The average value for the angular momentum of the entire body about the vertical axis was determined for each contact phase and each flight phase. Two-way ANOVA (2 movements×4 phases) was used to test the significance of the main and interaction effects. In addition, the angular momentum was categorized into head and trunk, right leg, left leg, right arm, left arm, both arms and both legs, and the pattern of change in each category during the normalized stride cycle was compared between 2 movements. Two-way ANOVA demonstrated a significant main effect for both factors with no interaction. In all phases, the average angular momentum in RC was directed more toward CCW as viewed from above than that in RS. Whereas the angular momentum of the head and trunk in RS changed periodically from positive to negative values, that in RC maintained positive values throughout the stride cycle. The angular momentum of the right leg in RC changed periodically in the same phase as in RS, but that of the left leg changed in the reverse phase. The left leg not only moved back and forth in RC, but also moved from side to side, allowing it to undergo circular motion in a direction opposite to the body's rotation in the horizontal plane. Presumably, this circular motion generated reaction effects on the adjacent segments, causing the head and trunk to gain sufficient angular momentum to keep facing toward the running direction.
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  • Koji Akashi, Mamoru Tanaka, Hiroaki Tanaka, Yasuki Higaki
    2015 Volume 60 Issue 2 Pages 589-601
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: September 05, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to examine the effects of strength output during recovery on intermittent exercise performance, and to evaluate the relationship between physical ability and intermittent exercise performance, including strength output. Test I consisted of a 20-m shuttle sprint followed by throwing a 4-kg medicine ball backwards during the 30-s recovery period; this was repeated 8 times. For test II, participants carried a 30-kg training bag a distance of 5 meters during each test I recovery period. Nineteen male university handball players performed test I and test II. Our results revealed the following:
    1.  Test II resulted in greater decreases in both anaerobic running power and anaerobic throwing power than test I.
    2.  There was a positive correlation between relative aerobic power and the retention rate of anaerobic running power during the 4th, 5th and 8th sets of test II.
    3.  There was a positive correlation between the strength index and retention rate of anaerobic throwing power during the 8th set of test II, and a positive correlation between body weight and the retention rate of anaerobic throwing power during the 6th and 7th sets of test II.
    These results indicate that with strength output during recovery, a high relative aerobic power is necessary to maintain intermittent anaerobic running power, and that muscle strength is important for maintaining intermittent anaerobic throwing power.
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  • Goro Moriki, Takashi Kurokawa, Kenta Nishiyama, Keita Akashi, Dohta Oh ...
    2015 Volume 60 Issue 2 Pages 603-616
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: October 15, 2015
    JOURNALS FREE ACCESS
      Changes in the physiological index and skill index resulting from long-duration baseball fielding practice were examined to obtain useful suggestions for training.
      Seven collegiate baseball players participated in fielding practice in the shortstop position. One set fielding practice lasted for 5 minutes at intervals of 17 seconds, and 12 sets were repeated. A rest period of 1 minute was allowed between the sets. As a physiological index, the heart rate (HR) was measured continuously every 5 seconds from 30 seconds prior to the start of the first set to the end of the final 12th set. The ratings of perceived exertion (RPE) and the blood lactate concentration (Lab) were measured at preinitiation (Pre) of the first set and after the end of each set. As a skill index, the catching score and the throwing score were measured at every trial.
      The peak HR in each set changed from 173±10 bpm in the third set to 163±10 bpm in the 12th set. The minimum HR during the rest period fluctuated between 110 and 120 bpm. The mean Lab increased rapidly from Pre until the peak value in the third set (5.7±4.1 mmol/l), and then decreased gradually to the 12th set (2.2±0.8 mmol/l) (p<.05). The mean RPE increased rapidly from Pre until the first set (12±2) (p<.05), and then increased gradually until the peak value in the 8th set (17±1) (p<.05), decreasing gradually thereafter until the 12th set (15±1). In the catching score, the number of attempts at 3 points decreased significantly and the number of attempts at 2 points increased significantly in sets 6-12 in comparison with sets 1-4 (p<.05, respectively). In the throwing score, the number of attempts at every point did not change significantly.
      The above results suggest that if fielding practice is continued at the frequency of every 17 seconds for a long duration, high performance can be effectively maintained when 1) fielding practice is divided into sets of several minutes with a short rest period between the sets, 2) a long rest period is interposed between several sets, and 3) carbohydrate is taken between several sets.
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  • Masaaki Kubo
    2015 Volume 60 Issue 2 Pages 617-633
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: November 02, 2015
    JOURNALS FREE ACCESS
      This study was conducted to examine the structure of “semantic generation” that occurs through experience of sports movements. First, by examining the body theory of Yuasa, we considered how, during the practice of sports movements, the body schema synchronizes with the body movements of others, the materials employed, and one's own body movements. Second, we analyzed the special experience of sports movements based on the model of triple cybernetics, arguing that synchronization of the body schema gives rise to the special experience. Finally, we discussed how this synchronization of the body schema during the practice of sports movements changes the relationship between one's self and the world.
    The results of our study were as follows:
    1)  Yuasa argues that the relationship between mind and body has a double structure, i.e. a surface structure and a basal structure, the former belonging to the area of consciousness, and the latter to the area of unconsciousness. He points out that a sort of body schema exists in the basal structure, and argues that subliminal action through the body schema occurs prior to consciousness.
    2)  In the practice of sports movements, the body schema synchronizes with the body movements of others. When batting in baseball, the batter synchronizes with the movement of the pitcher. When dancing in a pair, one dancer synchronizes with the movement of the other. Similarly, the body schema synchronizes with materials such as a ball, a bat, and so on. In tennis, the player synchronizes with the ball in order to hit it. And the body schema synchronizes with the individual's own body. When performing floor exercises, the gymnast synchronizes the body schema with the objective and physiological body.
    3)  Based on the model of triple cybernetics, the special experience of sports movements allows transcendence from the social system to the eco-system. The world consists of personal, social and eco (nature) systems. In the practice of sports movements, synchronization of the body schema arises at this level of the personal system so that it can lead into the eco-system.
    4)  This special experience in the practice of sports movements changes the relationship between one's self and the world. We are usually conscious of the existence of others as “Es” in the social system. However, in the eco-system individuals are conscious of the existence of others as “Du”. In this way, there is a change in the relationship between one's self and the world. This is “semantic generation” through experience of sports movements.
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  • Kazumichi Ae, Sekiya Koike, Takashi Kawamura
    2015 Volume 60 Issue 2 Pages 635-649
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: November 02, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to clarify the kinetic features of the trunk under different hitting-point height conditions (high, middle, and low) in baseball tee-batting. Twenty-three collegiate male baseball players (age: 19.8±1.3 yr, height: 1.74±0.04 m, whole-body mass: 74.1±6.2 kg, athletic career: 12.0±2.1 yr) participated. Three-dimensional coordinate data were captured using a VICON-MX system (12 cameras, 250 Hz), and kinetic data for the individual hands were collected using an instrumented bat equipped with 28 strain gauges (1000 Hz). Three kinds of tee-batting heights were set for each participant based on the upper and lower limits of the strike zone according to the baseball rule. The torso was modeled with the rigid upper and lower trunk segments connected by a torso joint with three axes: the ante/retro flexion, right/left lateral flexion, and right/left rotation axes. Kinetic variables, e.g. joint force and torque, mechanical power, and mechanical work, were obtained by inverse dynamic calculation. These data were expressed for a right-handed batter and normalized by the time of the forward swing from the swing start to the ball impact as 0-100%, and the time was divided into down-swing and level-swing phases in order to evaluate the mechanical work. From the last half of down-swing phase until ball impact, the retroflexion torque under the low condition was significantly larger than those under other conditions. The left rotation torque and positive torque power showed particularly large values in the level-swing phase regardless of the hitting-point height. The mechanical energy flow generated by the torso joint torque showed inflow from the lower trunk to the upper trunk, and outflow from the upper trunk to the individual upper arms regardless of the height condition over the forward swing. In addition, there were significant positive correlations between the positive mechanical work done by the joint torque about the right/left rotation axis and the maximum bat-head speed during the level-swing phase under the middle and low conditions. These results indicate that 1) the ante/retro flexion axis torque is needed to maintain the configuration of the upper trunk against the large centrifugal force exerted along the bat around the moment of ball impact, 2) the right/left rotation axis torque contributes to the generation of the large mechanical energy, the transfer of energy to the upper limbs, and the generation of the bat-head speed regardless of the height condition.
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Practical investigations
  • Kosuke Hiruma, Nobuaki Watanabe, Kenichi Mori, Mitsugi Ogata
    2015 Volume 60 Issue 2 Pages 651-665
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 15, 2015
    JOURNALS FREE ACCESS
      The purpose of the present study was to obtain basic data on sprint performance by students in physical education classes for 3 types of crouching start (CS)—bunch start (BS), medium start (MS), and elongated start (ES)— and standing start (SS), and to examine differences between males and females. The results are summarized as follows.
      1)  Over a 50-m running distance, the start method had no significant influence on performance among males in terms of most of the parameters analyzed. However, for BS, stride length in the first 1—2 steps was significantly shorter than for the other start methods.
      2)  Female's ES and SS were seen, and the running speed was seen compared with MS and BS and a high tendency was seen intentionally. For ES, the average stride and average start speed were intentionally greater than for MS and BS in males. The stride patterns during the distance and start phase were similar compared with other start methods before and behind ES and SS, and the possibility that CS (ES) was able to be accomplished in the condition similar to SS was thought.
      The above findings suggest that a graded learning method for CS in physical education classes would be beneficial for males, and that BS should be excluded in the initial stage of learning, whereas for females it is recommended that ES be employed to acquire a longer stride more easily in the introduction stage.
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  • Yasuo Shinohara, Masato Maeda
    2015 Volume 60 Issue 2 Pages 667-684
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: September 03, 2015
    JOURNALS FREE ACCESS
      Starting blocks are required for sprint starts in competitive races. Here, we examined the functional role of starting blocks at the start of a sprint. The participants were 9 sprinters (height: 174.8±3.7 cm; weight: 69.0±4.5 kg; personal best 100 m time: 10.89±0.34 s) who performed 2 kinds of sprint start: a crouch start with starting blocks (BS), and a crouch start without starting blocks (CS). Two force plates were placed under each block or under the participants' feet in the BS or CS, respectively, and were used to measure the force applied to the starting blocks or to the ground. Another 2 force plates were placed to measure the ground reaction force of the first and second steps after block clearance. The sampling frequency for these measurements was 1 kHz, and kinematic data were recorded using 4 high-speed cameras at 250 frames/s. Time from the start signal to take-off of the second step was significantly longer for CS than for BS, but there was no significant inter-group difference in the point of touchdown of the second step. The method of increasing the horizontal velocity of the center of gravity differed significantly by group and power in the horizontal direction during the block clearance phase, being significantly less for CS than for BS. Consequently, the horizontal impulse applied to the ground in CS was significantly less than that applied to the starting blocks in BS, and the duration of force application in CS was significantly longer. Furthermore, the horizontal impulse applied by the rear foot in CS was significantly less than that applied to the rear block in BS, and the horizontal impulse applied during the double stance phase in CS was significantly less than that in BS. These factors affect the extensional and rotational movements in the block clearance phase. Taken together, these results indicate that the crouch start can be effective when starting blocks are used. Therefore, starting blocks can be regarded as an essential tool for enhancing sprint start performance.
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Case study
  • Seiichiro Kihara, Kenji Kubo
    2015 Volume 60 Issue 2 Pages 685-699
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: August 25, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to confirm how many oral contributions and their type of content provide opportunities for participants to learn at a colloquium after a research lesson as school training at C Elementary School in B city, A prefecture on July 14th, 2014.
      The research was conducted by first dividing the conversation at the colloquium into the comments from different speakers. Then, each comment was divided into statements that made sense. Furthermore, each oral contribution was classified into 6 categories on the basis of “utterance classification category on the representation of practice”(Sakamoto, 2013): ① “Representation of the target class”, ② “Inference”, ③ “Representation of problems”, ④ “Assumption of possibilities”, ⑤ “Alternatives”, and ⑥ “Others”. Then, a comparison was made of the number of each of the 6 categories among the practitioner, observers, and advisers.
      Two results were obtained: First, oral contributions related to ② “Inference”, ③ “Representation of problems”, and ⑤ “Alternatives” were more numerous for observers and advisers than for the practitioner. These comments indicate problems and suggest countermeasures for a solution to the observed class to promote better practitioner teaching by providing valid information. Second, among the “utterance classification category on the representation of practice”, ③ “Representation of problems” and ⑤ “Alternatives” for the teachers who observed the research lesson were limited to the previously-provided 2 viewpoints. Meanwhile, ③ “Representation of problems” and ⑤ “Alternatives” for practitioner Teacher Z, an assistant principal and a principal as managerial staff, and a teachers' consultant and a faculty member as outside advisers included the contents other than the 2 viewpoints. In particular, ③ “Representation of problems” and ⑤ “Alternatives” of e. “The relationship between systematicness of the educational contents of the ball game and unit objectives” presented by the principal, the practitioner Teacher Z, the faculty member, and the assistant principal are considered to have provided the colloquium participants with an opportunity to review the material knowledge that the contents of the ball game consist of individual skills, tactics, and ideas for the rules.
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Materials
  • Atsurou Hougaku
    2015 Volume 60 Issue 2 Pages 701-714
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: June 16, 2015
    JOURNALS FREE ACCESS
      One of the characteristics of the German Democratic Republic's (GDR) sports policy was the large volume and variety of sports-related regulations. In this study, I investigated the time of creation, nature, content, and characteristics of the “Directive Regarding the Promotion of Physical Culture and Sports in the German Democratic Republic from 1956 to 1960” (“Direktive zur Entwicklung der Körperkultur und des Sports in der Deutschen Demokratischen Republik vom 1956 bis 1960”) —all of which have been unclear up until now— using DR5/561, a document maintained in the German Federal Archives. I considered the characteristics primarily through a comparison with earlier sports-related regulations.
      In summary, a number of points were clarified. First, there is a possibility that the directive was a top-secret document created sometime during or after September 1956. Furthermore, the State Committee for Physical Culture and Sport decided to forward the directive to the German Gymnastics and Sports Federation (DTSB) on February 4, 1957. Second, the directive comprised 7 sections (infant and youth sports; workers' popular sports; improvement of sports performance; science and the cultivation of experts; investment and construction work; sports instruments and materials/development; and financial affairs), the final 3 sections having been absent in previous regulations. Third, one of the characteristics of this directive was the establishment of mid- to long-term objectives, as in the GDR's Second Five-Year Economic Plan (1956—1960) with which it was issued in conjunction. Here, one can see the GDR's approach of trying to promote sports more systematically than in the past. Fourth, while the directive does not clearly specify the role of certain groups that had been leaders in the GDR sports world —such as the Free German Youth— it does specify the role of the DTSB, which was established in April of the following year. This suggests that the directive was a change in direction from a Soviet sports-system model. In other words, it was something created with the construction of a sports system unique to the GDR.
      It still cannot be determined whether the directive that is included in DR5/561 is the same as any of the documents found in GDR sports history books. This is because some points regarding the directive are still unclear, such as the exact time and date it was created, and which organizations other than the DTSB to which it was forwarded.
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  • Kyungjin Park, Yoshiko Murata, Akane Yamazaki
    2015 Volume 60 Issue 2 Pages 715-736
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 03, 2015
    JOURNALS FREE ACCESS
      This article is a continuation of a study conducted by Park and Murata (2013) in which they reviewed the large number of changes to theme-centered types of dance in the new physical education (PE) curriculum in Korea (2007 Revised Education Course) but which did not review the contents in detail. Based on their research, this article attempts to review the methods in which expression activities in Korea are actualized by examining published PE textbooks that were written in accordance with the 2007 revision of the curriculum. This article aims 1) to describe the actualization of the contents of expression activities in the new PE curriculum by reviewing the direction in which dance suggested in the national curriculum is treated in school classes, and 2) to suggest the future direction of dance education and PE in Japan and Korea by comparing the Korean results with the Japanese results, as reviewed in Park and Murata (2013).
      The types of activities suggested in Korean textbooks are almost the same as the optional activity examples suggested in the curriculum. Creative activity is treated as important. In every textbook, content is presented so that the student may understand the principles that exist in both dance and expressive sports. This is followed by a creative process which involves creating and presenting new dance works. In particular, the expressive sports that are suggested as expression activities are not suggested as competitions targeting the expressive activity, but instead are actualized to make creative activity possible. Also, expressive sports are actualized so that students can gain an understanding of the expression of esthetic appreciation. In comparison, the Japanese curriculum suggests detailed teachings of compulsory dance areas in grades 1 and 2 of middle school. It is expected that students will have more opportunity to experience dance, and the quality of education will be improved by giving teachers hints as to how they should teach. In contrast, in Korea, the expansion of opportunity for students is expected to enhance the experience of expressive and creative activities by broadening activity areas with various physical expression activities. The characteristics of, and differences between the two countries were also confirmed by reviewing the results of Park and Murata (2013) regarding the common terms and processing methods and development of learning shown in their respective dances. This article suggests that it will be necessary to check the existence of dance areas and to review the teaching content and methods for dance education in preparation for the change to theme-centered types of dance in Japan, in order to preserve dance education in the future. For Korea, it suggests investing in opportunities to experience the fun and attraction of dance in expression activity areas, to increase the identity of dance, and to reinforce the teaching and methods of improvisation and rhythm-type dances.
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  • Masahiro Kageyama, Chiharu Suzuki, Mineaki Iwamoto, Hajime Nakashima, ...
    2015 Volume 60 Issue 2 Pages 737-757
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 15, 2015
    JOURNALS FREE ACCESS
      The purpose of the present study was to clarify the profiles of the lower limb and trunk motion during baseball pitching in relation to their differences between the wind-up and the set positions, and to determine how the ball pitching velocity can be increased in the set position. The subjects were 12 high school baseball pitchers (age: 16.4±0.5 yr, height: 173.7±4.8 cm, weight: 64.8±8.1 kg). Pitching was assessed using a three-dimensional motion system and 2 multicomponent force plates. It was found that 1) the maximum and average pitched ball velocities were significantly lower in the set position than in the wind-up position, 2) the maximum ground-reaction force of the pivot and stride legs and the impulse of pivot during the stride phase (from the time of maximal stride knee height to the time of maximal anterior push-off force) were significantly lower in the set position than in the wind-up position, and 3) the maximum upper torso/trunk twist angular velocity and the pelvis/upper torso angular velocity at moment of the stride foot contact were significantly lower in the set position than in the wind-up position. These results indicate that 1) the ball pitching velocity in the set position is lower than in the wind-up position. In addition, the factors associated with this lower ball velocity are suggested to be 2) decreased momentum of the pivot leg and 3) decreased rotation motion of the trunk during the arm acceleration phase.
      Therefore, in order to increase ball pitching velocity in the set position, increasing the moment to the rear of the pivot leg during a short period and improvement of lower limb strength/power with the extension movement of the hip and knee joint may be important factors.
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  • Takumi Nakasuga, Shunsuke Sakata, Yoshio Sugiyama
    2015 Volume 60 Issue 2 Pages 759-772
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: July 16, 2015
    JOURNALS FREE ACCESS
      The purpose of this study was to examine the relationships among perceived motivational climates, goal orientations, and outcome expectations for physical education among junior high school students. Our basic study model was that the presence of 2 motivational climates in physical education classes would promote goal orientation, which in turn would increase students' outcome expectations. The sample comprised 813 junior high school students (mean age=13.7±0.9 years). The measures used included a questionnaire on motivational climates in physical education (performance climates with 3 subscales, teacher's promotion of performance orientation, class performance orientation, students' worries about mistakes and mastery climates comprising 4 subscales, teacher's promotion of mastery orientation, class mastery orientation, co-operation, fairness), a scale assessing goal orientations (students' ego orientation and students' task orientation), and a scale assessing outcome expectations (positive and negative outcome expectations). The validity of this model was verified using structural equation modeling. The model was demonstrated to be valid. Furthermore, the results of this study suggested the following processes: (1) Class performance orientation and students' worries about mistakes had a positive influence on students' ego orientation, which in turn had a positive influence on positive outcome expectation and negative outcome expectation. (2) Class performance orientation had a positive influence on positive outcome expectation, whereas students' worries about mistakes had a negative influence on positive outcome expectation. (3) The teacher's promotion of performance orientation and students' worries about mistakes had a positive influence on negative outcome expectation. (4) The teacher's promotion of mastery orientation, class mastery orientation and co-operation had a positive influence on students' task orientation, which in turn had a positive influence on positive outcome expectation, whereas it had a negative influence on negative outcome expectation. (5) Class mastery orientation and co-operation had a positive influence on positive outcome expectation. In conclusion, to enhance students' positive outcome expectation, it is important for teachers to cultivate a climate of both mastery and performance in physical education classes.
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  • Fuminori Takayama, Hisashi Mori, Mayuko Ando, Masayoshi Yamamoto
    2015 Volume 60 Issue 2 Pages 773-782
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: September 02, 2015
    JOURNALS FREE ACCESS
      The main purpose of this study was to investigate anthropometry and body composition in 26 male ultramountain runners who participated in Trans Japan Alps Race 2014, a multi-stage ultramountain running race over 415 km to be covered within 5-8 days. The second purpose was to investigate the changes in skinfold thickness during the race. Before the race, all participants were examined in terms of body weight, BMI, skinfold thickness at 8 sites and estimated percentage body fat. In addition, the finishers (n=14) were re-examined in the post-race period. The main findings are summarized below.
    1.  The participants had a mean (±SD) body weight of 62.3±5.1 kg, a BMI of 21.5±1.4 kg/m2, a sum of 8 skinfold thickness of 57.7±15.5 mm, and an estimated percentage body fat of 12.0±2.4%. There were no significant differences in any parameters between the finishers and the non-finishers.
    2.  The sum of 8 skinfold thickness in the finishers was significantly reduced by 11.3% after the race (Pre : 55.0±13.6 mm, Post : 48.8±12.1 mm), representing a dramatic response in comparison with a previous study that investigated ultramarathon runners in a 100-km ultramarathon race (0.9%).
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  • Kenryu Aoyagi, Kaori Ishii, Ai Shibata, Hirokazu Arai, Hanako Fukamach ...
    2015 Volume 60 Issue 2 Pages 783-792
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: October 02, 2015
    JOURNALS FREE ACCESS
      School-based extracurricular sports activities are beneficial for positive youth development. However, there is a shortage of appropriate in-school coaches, and therefore recruitment of external coaches has been considered as one solution to this. A previous study has reported 4 model strategies of organizational promotion to recruit external coaches. These 4 models included “compensational support”, “staff introduction”, “delivery of collegiate students”, and “cooperation with company”. In order to promote the further development and popularization of these organizational trials, user-side evaluation is necessary. Therefore, the purpose of the present study was to clarify the strengths and problems related to these 4 organizational promotion strategy models when recruiting external coaches for school-based extracurricular sports activities from the viewpoint of teachers. The participants were 12 teachers who worked in public junior high or high schools. All of them had experience of coaching school-based extracurricular sports activities. Face-to-face semi-structured interviews were conducted with the individual participants, and all interview data were transcribed. Then, similar meaning units were grouped into themes with respect to the 4 models, strengths and problems. As a result, many specific themes for each model emerged. For instance, with regard to “compensational support”, monetary support was regarded as a strength, although the early application period was a problem. With regard to “staff introduction”, adequacy for beginners was a strength, but lack of mediation organization was a problem. With regard to “delivery of collegiate students”, regular coaching was seen as a strength, but worry over not choosing a delivered external coach was a problem. With regard to “cooperation with company”, high coaching skill was a strength, but an expensive coaching fee was a problem. Additionally, comprehensive opinions about all the models were reported, such as lack of information about the system and the need for educational coaching. These similarities and differences in the results indicated the importance of mediation system design considering the regionality and situation of the school-based extracurricular sports activity. Effective publicity and re-examination of financial manager is also needed. In addition, mediation organization and teachers should arrange previous meetings with external coaches to understand their human qualities and educational attitude. Furthermore, it would be valuable to develop the quality of external coaches through previous training or workshops. Finally, changes in the application period for each mediation system are suggested.
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  • Shohei Takamatsu, Yasuo Yamaguchi
    2015 Volume 60 Issue 2 Pages 793-806
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: October 02, 2015
    JOURNALS FREE ACCESS
      This study was conducted to examine the competency of Kokoyakyu (Japanese high-school baseball) managers by developing and then applying a suitable measurement scale. First, we interviewed 6 Kokoyakyu managers, identifying 245 competency items. To categorize these items, one professor and 4 graduate students in sport sociology conducted a panel discussion. This yielded 48 competency items that were divided into 10 categories. Second, to appraise the reliability and validity of the resulting scale, we sent questionnaires to 1,000 managers, and received 421 replies. Item-total correlation analysis, exploratory factor analysis, and confirmatory factor analysis revealed 6 factors comprising 24 competency items: (1) trust relationship (6 items), (2) powers of observation (4 items), (3) educational guidance (3 items), (4) autonomy support (4 items), (5) relationship of supporters (3 items), and (6) skill and tactics instruction (4 items). The indices of model data fit were χ2/df=1.72, GFI=.87, CFI=.90, and RMSEA=.058. Assessment of construct validity comprised 3 components: convergent validity (Cronbach's alpha, average variance extracted, and construct reliability), discriminant validity, and content validity. The scale was observed to be reliable and valid. Comparison of the scale based on managers' profiles indicated significant differences based on team results, experience in developing players on the path to professional baseball, and years of experience.
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Secondary publication
  • Ryo Ogaki, Masahiro Takemura, Koichi Iwai, Shumpei Miyakawa
    2015 Volume 60 Issue 2 Pages 807-814
    Published: 2015
    Released: December 18, 2015
    [Advance publication] Released: June 16, 2015
    JOURNALS FREE ACCESS
      This prospective cohort study examined the associations of shoulder dislocations, instability or rotator cuff injuries in collegiate rugby union players with potential risk factors recognized in preseason medical screening examinations. The study subjects were 69 elite rugby players from one university rugby club. Basic demographics, injury experience and current physical findings were assessed, and shoulder injuries sustained during 2 playing seasons were recorded. Risk factors for shoulder injuries were determined using a logistic regression model. Fifteen players sustained shoulder injuries during the 2 seasons. A history of injury (OR, 6.56; 95%CI, 2.04—20.98; p=0.00), a positive result in the load and shift (LAS) test (OR, 2.55; 95%CI, 0.92—7.06; p=0.07) and the internal/external rotational (IR/ER) muscle strength ratio (OR, 1.39; 95%CI, 1.08—1.77; p=0.00) were associated with shoulder injuries. A history of injury, a positive LAS test result, and the IR/ER muscle strength ratio are important risk factors for injury in collegiate rugby players.
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