著者

Kenta Karakida Hironobu Tsuchiya

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202217, (Released:2023-06-15)

参考文献数

35

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Previous studies have shown that self-consciousness traits are closely related to choking under pressure (Baumeister, 1984; Wang et al., 2004). However, it has not be distinguished between private and public self-consciousness. This study investigated the influence of private and public self-consciousness of athletes on the factors of choking under pressure. 281 subjects were asked to respond to a questionnaire on choking factors (Murayama and Sekiya, 2012) and a self-consciousness scale (Tsuji, 1993), and data from 253 subjects were analyzed. The results showed that higher private and public self-consciousness had more choking experience. Furthermore, we examined the influence of private and public self-consciousness on the factors of choking and found that private self-consciousness showed significant positive effects to be associated with changes in motor control, vicious circles, abnormal physical sensations, and conscious processing (attention to movement). In contrast, public self-consciousness showed significant positive effects on changes in motor control and vicious circles, perceptual and cognitive confusion, feelings of physical heaviness and weakness, passivity, and safety-oriented strategies. The results indicate that private and public self-consciousness affect different factors of choking under pressure.

著者

Rei AMEMIYA

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202053, (Released:2023-02-17)

参考文献数

32

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This study investigates the relationship between the individual characteristics of athletes and the perceived impact of COVID-19 on their daily lives and athletic activities. Participants were 476 Japanese athletes (250 males and 226 females; mean age = 28.39 ± 6.53 years) registered as respondents at an Internet research company and who met the athletic-related inclusion criteria. The investigation took place from the 6th–13th April 2020, just before the Japanese government declared a state of emergency due to the COVID-19 pandemic. Participants answered questions related to socio-demographic variables, the impact of COVID-19 on daily life and athletic activities and completed the Kessler Psychological Distress Scale. The results showed that the emergency declaration area, marital status, and gender were directly related to annual income, and that they indirectly influenced the impact of COVID-19 on athletes’ daily lives and athletic activities through annual income. Additionally, although a state of emergency being declared in the region impacted the daily lives of all participants and their athletic activities, unmarried and female athletes with low incomes were among the most affected by COVID-19-related measures.

著者

Midori Kondo Hironobu Tsuchiya Takayuki Sugo

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.20, pp.193-207, 2022 (Released:2022-12-15)

参考文献数

55

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Pride is an emotion that may influence a competitive athlete's sports performance and mastery. The purpose of this study was to develop a scale to measure the pride traits in sports (Trait Pride Scale for Athletes: TPSA) and examine the characteristics. University student-athletes completed the TPSA, focusing on subjective emotional episodes and other scales of important personality constructs including self-esteem, resilience, authenticity, and narcissism (Study 1), and grit (Study 2). The factor analysis of the TPSA items indicated a four-factor structure: (a) Relationship, (b) Endurance/Diligence, (c) Athletic Self-Identity, and (d) Superiority. There were no gender differences in overall TPSA scores. Internal consistency by Cronbach’s alpha and the retest reliability were verified acceptable. The TPSA scores were positively correlated with all of the other psychological scales, confirming convergent validity. Findings provide initial insight into the structure of pride in sports contexts. Specifically, these findings suggest that the athletes’ proneness of pride is a multidimensional construct that involves not only intrapersonal factors but also interpersonal factors.

著者

Jun Mizushima Joanne Kyra Loo Shermain Lou Clifford J. Mallett

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202218, (Released:2022-11-24)

参考文献数

22

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Sport coaches develop their coaching knowledge and identity as coaches through their life experiences over time. However, limited knowledge exists for what motivates youth coaches in Asia to coach, how they learn their craft, and how they develop as coaches. Therefore, the purpose of this study was to investigate the developmental pathways of youth sport coaches in Singapore. Eleven youth sport coaches in Singapore (10 males, 1 female) from a range of sports were selected to take part in semi-structured interviews consisting of three sections: coaches' profile, valued learning experience, and motivation. Qualitative thematic analysis was implemented to understand the key aspects of coach development in their coaching careers. Data yielded six main categories about valued learning experiences: (1) interaction with other coaches, (2) learning from overseas practice, (3) athletic experience, (4) on-the-job experience, (5) mentoring, and (6) coach education program. Two main categories about coach motivation were identified. These were: (1) initial motivation to be a coach—sense of purpose and (2) motivation to continue coaching—enjoyment, satisfaction, and passion.

著者

Ryohei Yamakata Hiroki Uwagawa Takeshi Ogawa

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202109, (Released:2022-03-25)

参考文献数

28

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This study aimed to investigate whether four weeks of jump and running drill training with a mini-trampoline affects sprint running, standing long jump, and drop jump performance. Fifteen healthy male students were assigned to either the trampoline training (T; n=8) or ground training (G; n=7) group. All participants performed jump and running drill training using either a mini-trampoline or over ground two times per week for 4 weeks. Before and after the training period, the participants performed a 50 m sprint run, a standing long jump, a drop-jump, and a ground reaction force evaluation test during a 20 m sprint. The pre- and post-training results were compared. The 50 m sprint record improved in both groups (P<0.01). The jump height of the drop-jump test decreased in the T group (P<0.05). The standing long jump distance did not change after the training period in either group. There was no significant change in impulse in either direction before and after the training period during the 20 m sprint run. Our results suggest that jump and running drill training using a mini-trampoline did not have any specific effect compared to jump and running drill training on the ground.

著者

Kotomi Shiota

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.15, pp.96-103, 2017 (Released:2018-02-15)

参考文献数

24

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Objective: To analyze the effects of intradialytic resistance training on physical function in 8 hemodialysis patients aged ≥60 years. Method: Physical function, blood pressure, heart rate, and biochemical data were analyzed before and after 3 and 12 months of exercise therapy. Focusing on muscle strengthening of the trunk and legs while on bed rest, the exercise load of the intervention was individualized for each patient. Results: Significant differences were observed in ankle plantar flexor strength, the Timed Up and Go test, and maximum walking speed between before and after 3 months of intervention. However, no significant differences were observed from 3 to 12 months, indicating that there was no long-term improvement upon low-to-medium resistance training during hemodialysis. Conclusion: Further studies with increased sample sizes are required to elucidate the appropriate intensity, frequency, and duration for an effective resistance training program in this population.

著者

Midori Kondo Hironobu Tsuchiya Takayuki Sugo

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202112, (Released:2022-08-05)

参考文献数

53

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Pride is an emotion that may influence a competitive athlete’s sports performance and mastery. The purpose of this study was to develop a scale to measure the pride traits in sports (Trait Pride Scale for Athletes: TPSA) and examine the characteristics. University student-athletes (N = 463) completed the TPSA, focusing on subjective emotional episodes and other scales of important personality constructs including self-esteem, resilience, authenticity, and narcissism. The exploratory factor analysis of the TPSA items indicated a four-factor structure: (a) Relationship, (b) Athletic Self-Identity, (c) Endurance/Diligence, and (d) Superiority. Regarding the gender differences in the TPSA subscale scores, female athletes experienced significantly more pride in Endurance/Diligence. Internal consistency was verified by Cronbach’s alpha and supported the reliability. The TPSA scores were positively correlated with all of the other personality scales, confirming convergent validity. In addition, partial correlation coefficients by controlling for other personality variables indicated that Relationship, Athletic Self-Identity, and Endurance/Diligence had a positive correlation with authenticity and resilience, whereas Superiority correlated with self-esteem and narcissism. Findings provide initial insight into the structure of pride in sports contexts. Specifically, these findings suggest that the athletes’ proneness of pride is a multidimensional construct that involves not only intrapersonal factors but also interpersonal factors.

著者

Erlacher Daniel Masato Fujii Shunichi Tazuke Tetsuji Sugiyama Ganzert Florian Stumbrys Tadas Schredl Michael

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.20, pp.117-122, 2022 (Released:2022-07-01)

参考文献数

29

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In a previous questionnaire study with German professional athletes, we showed that the prevalence of lucid dreaming in athletes is 57% and that about 5% of athletes use their lucid dreams to practice sport skills while asleep. The present study applied a Japanese translation of the same questionnaire to a Japanese sample of college athletes to explore cultural differences. We found that about 41% of Japanese athletes stated that they experienced a lucid dream at least once in their lives, 18% experienced them once a month or more frequently, while 3.6% of athletes used lucid dreams for their sport practice. The frequency of lucid dreams in Japanese athletes was lower than in the German athletes, indicating potential cultural differences. Yet lucid dream practice does appear to have a cross-cultural applicability.

著者

Shigeharu Akimoto

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.20, pp.A1-A10, 2022 (Released:2022-06-28)

参考文献数

13

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The Paralympic Games are currently in the public spotlight not only as a sporting spectacle but also as a vehicle for empowering individuals with disabilities in society. However, previous research indicates that the Paralympic Games currently cater for a limited variety of impairments, which perhaps reflects a limitation of the Games in this respect. The aim of this study was to determine whether this premise is valid by considering the empowerment of individuals in society via the Paralympic Games, focusing on groups including both mobility and hearing impairment. Quantitative data were recovered from a questionnaire survey disseminated to lower secondary departments of special needs education schools for the physically challenged (n=44, collection rate: 80.0%), lower secondary departments of special needs education schools for the deaf (n=119, collection rate: 85.6%) and a regular lower secondary school (n=145, collection rate: 83.8%) used as a control group in prefecture “A” via postal mail. Results were generated using an analysis of variance approach and χ2 test. The data indicated that the Paralympic Games as a vehicle of empowerment is only valid for those with mobility impairment, and not for those with hearing impairment. This suggests that empowerment through the Paralympic Games may only be effective for individuals with impairments that qualify them for entry into the Paralympic Games, while excluding those with impairments that do not. Ancillary findings of this study suggest that the majority of those with disabilities were uncertain about hearing impairment and the eligibility criteria of the Paralympic Games. It is also suggested that the Olympic Games have some positive effects in terms of empowering individuals with disabilities in society.

著者

Ryuichi Ajisaka

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.4, no.Special_Issue_2_2006, pp.360-369, 2006 (Released:2008-01-25)

参考文献数

23

被引用文献数

1 1

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In order to exercise safely, proper exercise prescription based on each individual's physical fitness and health status is needed. An intensity equivalent to the ventilatory threshold level has been recommended in terms of safety of aerobic exercise, and we confirmed its safety in very elderly subjects (older than 75 years) if they had no contraindications to exercise. More than 20% of the subjects with sedentary lifestyles and lower physical fitness had deleterious symptoms such as excessive blood pressure elevation, dangerous arrhythmias, and myocardial ischemia during exercise testing. Therefore, evaluation of physical fitness level enables optimal exercise prescription for aerobic exercise in the elderly, and low-level intensity (40% of VO2max) is recommended for those subjects. Excessive blood pressure elevation was frequent in greater than 60% of 1RM lower-leg resistance exercise in the elderly subjects. Therefore, 40% of 1RM intensity is recommended in terms of safety in very elderly-aged people or those with hypertension. Proper breathing technique avoiding the Valsalva effect is effective to minimize blood pressure rise during resistance exercise. Aerobic exercise training could have a lowering effect on blood pressure rise during resistance exercise in the elderly subjects. It is noteworthy that the frequency of deleterious symptoms during exercise could not decrease after short-term aerobic exercise training in the elderly.

著者

Ryo Ogaki Miki Nariai Gento Otake Ayane Ogura Taiki Murakami Masahiro Takemura

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202117, (Released:2022-04-15)

参考文献数

18

被引用文献数

2

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A high risk of ankle injury is associated with rugby; however, current epidemiological data on rugby-related ankle injuries are limited to specific age and competition levels. This study aimed to clarify the epidemiological characteristics of ankle sprains by longitudinally investigating their incidence, severity, and burden in men's collegiate rugby. Ankle sprains that occurred during rugby matches and training in 128 male collegiate rugby players were investigated across three seasons (2017 – 2019). The incidence of ankle sprain was 1.21 injuries/1000 player-hours (PHs). The risk of occurrence during matches (18.18 injuries/1000 PHs) was 25.6 times higher than that during training (0.71 injuries/1000 PHs). The mean severity of ankle sprain was 24.7 days. The injury burden tended to be higher in the match season than in the training season. The main injury mechanisms were thought to be related to contact play and stepping (non-contact play). In addition, a high rate of initial sprains was observed in this study. Ankle sprain prevention is important in collegiate rugby players.

著者

Yuto Yasuda

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.20, pp.19-25, 2022 (Released:2022-04-02)

参考文献数

48

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Different cultures have different societal structures and different communication style. Additionally, how sports are organized varies from country to country in terms of structure. These factors make athletes across the world demonstrate different psychological characteristics. Despite these differences, these cultural impacts have been paid little attention to, and psychological universality has been explored in the field of sport psychology even though the importance of cultural differences is remained. This review article explores the consideration of cultural psychology within the domain of sport psychology. Specifically, this article compares East Asian culture and North American culture from an achievement motivation perspective. Self-construal, regulatory focus theory, self-determination theory, and achievement goal theory are investigated in order to compare the two cultures. It is recommended that future researchers in the domain of sport psychology refer to both cultural differences as well as psychological universality to deepen insight into the sport psychology field. Practitioners in sport psychology such as mental performance consultants and coaches, are also suggested to consider cultural differences in order to effectively communicate with players and implement more effective interventions.

著者

Yuiko Matsuura Satoshi Iizuka Keisuke Koizumi Keisuke Okuno Koji Kaneoka

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.201820, (Released:2019-01-31)

参考文献数

13

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Trunk stabilization exercises improve injury prevention and performance, but the effect of deep trunk muscle training for underwater competitive performance and posture has not been clarified. If trunk stability can be obtained immediately after trunk stabilization exercises, such exercises may lead to performance improvements during underwater swimming and improve lumbar lordosis alignment during swim motions. The purpose of this study was to clarify the immediate effects of deep trunk muscle training on lumbar lordosis angle and swimming speed in underwater motion. The trial examined underwater motion before and after two different types and intensities of trunk stabilization exercises (low-intensity and high-intensity). Underwater motion was observed with an underwater high-speed camera placed 7.5 m from the pool wall, while lumbar lordosis angle was measured from the angle formed by markers affixed to the Th12, L3, and S1. During the glide swim, dolphin kick, and flutter kick trials, the maximum lumbar lordosis angle was calculated. Lumbar lordosis angle and swimming speed were calculated before and after two different intensities of trunk exercise interventions. There were significant differences in lumbar lordosis angle after both exercises during all three underwater motions. The high-intensity intervention elicited a significantly lower lumbar lordosis angle during glide swim, dolphin kick, and flutter kick, while swimming velocity was also improved during glide swim and flutter kick (P<0.05). Performing trunk exercise before practice or competition may help improve competition performance by reducing underwater resistance.

著者

Yuto Yasuda

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.202123, (Released:2022-03-03)

参考文献数

48

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Different cultures have different societal structures and different communication style. Additionally, how sports are organized vary from country to country in terms of structure. These factors make athletes across the world demonstrate different psychological characteristics. Despite these differences, these cultural impacts have been paid little attention to, and psychological universality has been explored in the field of sport psychology even though the importance of cultural differences is remained. This review article explores the consideration of cultural psychology within the domain of sport psychology. Specifically, this article compares East Asian culture and North American culture from an achievement motivation perspective. Self-construal, regulatory focus theory, self-determination theory, and achievement goal theory are investigated in order to compare the two cultures. It is recommended that future researchers in the domain of sport psychology refer to both cultural differences as well as psychological universality to deepen insight into the sport psychology field. Practitioners in sport psychology such as mental performance consultants and coaches, are also suggested to consider cultural differences in order to effectively communicate with players and implement more effective interventions.

著者

Noriko Otsuka

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.4, no.Special_Issue_2006, pp.198-207, 2006 (Released:2008-01-25)

参考文献数

9

被引用文献数

1 1

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Falconry is one of the most traditional co-hunting styles of Japan. Public patronage began in the 4th century; it was the exclusive preserve of nobles and feudal lords until the 19th Century. The culture especially flourished in the 17th to 19th centuries under the family of the Tokugawa shogun. Some 1,600 km2 of Edo (presently Tokyo) served as a falconry preserve (Otakaba). Because all hunting of animals was prohibited inside of it, Otakaba also served the role of game preserve. After the Meiji Restoration, the Otakaba system lapsed and falconers lost their jobs. As the Edo area developed, new foreign customs changed the Japanese life style. The Imperial Household Ministry (presently Imperial Household Agency) preserved falconry as a time-honored art on the wishes of the Emperor Meiji. Falconers trained hawks and falcons, and worked at duck netting preserves (Kamoba). But following World War II, all this traditional hunting has ceased. On the other hand, private falconry activity is opening up. After his retirement from the Imperial Household Agency, Mr. Kaoru Hanami was invited by his pupils to become the president of The Japanese Falconers Association. He taught them to carry on the art of falconry that had been handed down to him, the Suwa hawking school, which is one of the most traditional styles. In his school, the hawk was considered to be an avatar that should be respected, but modern people did not understand or think that way. Because of his concern about the tendency of the people to look down on hawks as pets or mere hunting tools, he propounded a coined expression, “Jinyoh-Ittai” (man and hawk as one) to build a relationship of equality. There are other schools and dedicated groups that are trying to do sports falconry, and many clubs organized by pet owners in Japan. Also, in recent years, development of telemetry systems promises to make falconry more efficient.

著者

Mizuho Takemura

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

vol.16, pp.A25-A36, 2018 (Released:2018-03-15)

参考文献数

39

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Medical technology has made remarkable advances in recent years. On the one hand, these advances have the benefit of contributing to the happiness of humankind; on the other hand, they can raise various ethical and social issues, precisely because they are applied to individual humans. One such issue is enhancement technology, which can be used not only for the purpose of treating disease, but also for improving or enhancing the body or mind; humans themselves can become subject to alterations without any medical purpose. Body enhancement used to improve athletic performance is of particular concern in competitive sports. In this study, body enhancement was considered to be an act of pursuing a better-performing body, and examined the issues related to “better-ness” in this context from an ethical viewpoint. Specifically, I (1) elucidate the meaning of the word “better-ness” within the phrase “better performing” and (2) examine whether the act of pursuing a body that is “better” is an act of overall human betterment by engaging in an ethical discussion of its pros and cons. I use the principle of act described in Kant's practical philosophy as a framework for discussion. With regard to (1), I conclude that the meaning of “better” in the context of body enhancement in competitive sports is defined by theoretical (logical) judgment, and not by moral judgment. With regard to (2), I describe what an unacceptable act is according to Kant's Formula of the End in Itself. I also present the limits of this study, and point out the need to clarify in future studies the concept of what comprises human nature.

著者

Kosuke Takeuchi Masatoshi Nakamura Hironobu Kakihana Fumiko Tsukuda

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.201829, (Released:2019-04-24)

参考文献数

37

被引用文献数

2 15

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[Purpose] The purpose of the present study was to investigate static stretching and dynamic stretching protocol.[Methods] 138 coaches of 21 different sports completed a self-reporting questionnaire. The questionnaire was split into four sections and contained fixed-response questions. Section One identified participant demographics. The second and third sections required the participants to detail the static and dynamic stretching they used. The fourth section of the questionnaire identified how participants learned about stretching.[Results] There were 126 coaches using static or dynamic stretching, while 12 coaches did not. Thirty-nine coaches used only static stretching, 10 coaches used only dynamic stretching, and 77 coaches used both types of stretching. The purposes of static stretching were to increase flexibility and to prevent injuries. The purposes of dynamic stretching were improvement of performance and prevention of injuries. The duration of one bout of static and dynamic stretching in a warm-up were 21.8 ± 13.2 and 22.1 ± 16.2 seconds, respectively. A common way to learn about stretching was participation in training sessions.[Discussion] Coaches should use SS for a greater length of time to achieve their purposes. The results of the present study showed gaps between evidence and practice.

著者

Kentaro Chuman Yoshihiro Hoshikawa Tomomi Iida Takahiko Nishijima

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.1110030079, (Released:2011-10-07)

参考文献数

18

被引用文献数

5 6

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The study investigated the Yo-Yo intermittent recovery level 1 and level 2 tests (YYIR1 and YYIR2) performed by soccer players at puberty (U-13) and post-puberty (U-17) and related the YYIR1 and YYIR2 results to anaerobic and aerobic fitness. The subjects were sixteen male pubescent players aged 13.3(0.2) yrs (U-13) and fifteen male post-pubescent players aged 17.0(0.6) yrs (U-17). The subjects performed YYIR1 and YYIR2 on artificial turf and were also measured for fat-free mass (FFM), Wingate anaerobic test and VO2max during treadmill running in a laboratory. The results in YYIR1 and YYIR2 (2365 and 843 m) for the U-17 were significantly higher than the U-13 (1963 and 550 m). Results from YYIR1 and YYIR2 in the U-17 correlated significantly with VO2max (r=0.76 and 0.53) but not with Wingate anaerobic test, whereas YYIR1 and YYIR2 results in the U-13 correlated significantly with Wingate anaerobic test (r=0.61 and 0.64) but not with VO2max even though they showed high VO2max levels. The correlation coefficient of VO2max with YYIR1 and YYIR2 in the U-17 was equivalent to those reported in adult players and indicated that VO2max determined YYIR1 and YYIR2 performances moderately and highly in post-pubescent players. However, neither of the YYIR1 and YYIR2 performances in the U-13 reflected aerobic fitness but did reflect anaerobic fitness.

著者

Kiuchi Atsushi Shimegi Satoshi Tanaka Ippei Izumo Nobuo Fukuyama Ryo Nakamuta Hiromichi Koida Masao

出版者

一般社団法人 日本体育学会

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

no.4, pp.10-18, 2006

被引用文献数

3

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The purpose of this study was to investigate the effects of different intensities of resistance exercise training on established bone loss in ovariectomized (ovx-ed) rats by densitometry and histomorphometry. Thirty Female Wistar rats were ovx-ed or sham-operated (SHM) at 3 months of age and maintained untreated for 5 months after surgery to establish osteopenia. When they reached 8 months, the ovx-ed rats were divided into four groups in accordance with varying weights applied to a squat-training device: The weight classifications were 1) kept sedentary (OVX); 2) lifted 0 g (LOW); 3) 750 g (MID); and 1500 g (HIGH). The rats in the three training groups performed weight-lifting of 10 reps, performing 2 sets per day, 3 days a week for a ten week period. The Femora and tibiae were removed from each rat and were used for analyses. Ovx induced a significant loss of total BMC in all the bones tested. The ovx-induced femoral BMC loss was observed at all locations tested on the bone (proximal, shaft, and distal), and exercise-intensity dependent restoration was found at the proximal and the distal sites, but not at the shaft. In the tibia, ovx-induced significant bone loss occurred only at the proximal metaphyseal site. The training increased the tibial BMC of all sites in an exercise-intensity dependently, irrespective of the degree of ovx effect. At the tibial shaft, the training increased the cortical bone mass significantly above sham level by the bone apposition at the periosteum. At the proximal tibial metaphysis, exercise had no effect on the cancellous bone volume after ovx-induced bone loss. This finding suggests that the exercise induced bone increase in the ovx-ed rats was from cortical bone, not from cancellous bone, at least in the proximal tibia. These findings indicate that the weight-lifting exercise in rats reversed the ovx-induced bone loss in an exercise-intensity dependent and site-specific manner, even in established osteopenic skeleton 5 mon after ovx.

著者

Keita Suzuki Satoshi Nagai Koichi Iwai Ryo Ogaki Takuo Furukawa Masahiro Takemura

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

International Journal of Sport and Health Science (ISSN:13481509)

巻号頁・発行日

pp.201925, (Released:2020-04-06)

参考文献数

31

被引用文献数

2

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The present study aimed to determine the mechanisms of mild cervical injuries caused by tackling in a rugby union. This study enrolled 137 male players from a Japanese collegiate rugby union club during the 2009–2013 seasons. Twenty-nine (53.7%) of 54 incidents leading to mild cervical injury were identified from match video records and injury data that were reported under the definition of medical attention. In addition, all tackles by players in the same match in which they sustained cervical injury were extracted as a control cohort. All tackles were coded according to eleven characteristics of three tackle phases. Twenty-one tackles were the main events leading to mild cervical injury. The likelihood of tackler-associated mild cervical injuries was significantly higher when tacklers had no time to face forward at the offside line before tackle situations, tackles with incorrect tackler head positions, and not using arms after initial contact. These results suggest that further investigation is needed to determine specific tackling characteristics considering the three tackle phases and their combined effects.