著者

Senshi Fukashiro Thor F. Besier Rod Barrett Jodie Cochrane Akinori Nagano David G. Lloyd

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.3, no.Special_Issue_2005, pp.272-279, 2005 (Released:2008-01-23)

参考文献数

29

被引用文献数

22 36

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The purpose of this study was to perform a detailed kinematic, kinetic, and electromyographic comparison of maximal effort horizontal and vertical jumping. It was of particular interest to identify factors responsible for the control of jump direction. Eight male subjects performed maximal horizontal jumps (HJ) and vertical jumps (VJ) from a standing posture with a counter movement. Three-dimensional motion of the trunk, pelvis, and bilateral thigh, shank, and foot segments were recorded together with bilateral ground reaction forces and electromyographic (EMG) activity from seven right leg muscles. Relative to the VJ, the trunk is displaced further forward at the beginning of the HJ, through greater ankle joint dorsiflexion and knee extension. The activity of the biarticular rectus femoris and hamstrings were adapted to jump direction and helped to tune the hip and knee joint torques to the requirements of the task. The primary difference in joint torques between the two jumps was for the knee joint, with the extension moment reduced in the HJ, consistent with differences in activation levels of the biarticular rectus femoris and hamstrings. Activity of the mono-articular knee extensors was adapted to jump direction in terms of timing rather than peak amplitude. Overall results of this study suggest that jump direction is controlled by a combination of trunk orientation at the beginning of the push-off and the relative activation levels of the biarticular rectus femoris and hamstring muscles during the push-off.

著者

Kenji Tauchi Toshinori Endo Mitsugi Ogata Akifumi Matsuo Shigeo Iso

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.6, pp.78-84, 2008 (Released:2008-08-09)

参考文献数

13

被引用文献数

10 18

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The purpose of this study was to clarify the characteristics of jump ability in elite adolescent male athletes for the purpose of comparing them to healthy coeval males by referring to the results reported by Endo, et al., (2007). One hundred and twenty elite male athletes (alpine skiers, fencers, soccer players, track and field sprinters and jumpers, and weight lifters) aged 18 to 24 yrs and 316 healthy males aged 19 and 20 yrs performed countermovement jumps (CMJ) and five- repeated rebound jumps (5RJ) on a mat switch system. CMJ and 5RJ abilities were evaluated by jump height and RJ-index (=jump height/ground contact time), respectively. Although the jump height in CMJ and the RJ-index in 5RJ developed from ages 6 to 18 yrs, these values reached a plateau between the ages of 18 and 20 yrs in healthy males, elite athletes further developed after age 18. When the values for the healthy males in the present study were added to the results obtained for 1137 boys by Endo, et al., (2007), the regression line and correlation coefficient between jump height in CMJ and the RJ-index in 5RJ changed only slightly. However, the values for elite adolescent athletes tended to appear in the upper right from the population ages of 6 to 20 yrs; moreover, the scattering exhibited wide variation. The results revealed that although jump ability in healthy adolescent males changed little after age 18, jump ability in elite coeval athletes were superior after age 18 and that individual differences increased according to the length of specific training in each sport.

著者

Yutaka Shimizu Michiyoshi Ae Norihisa Fujii Hiroyuki Koyama

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.201817, (Released:2018-10-25)

参考文献数

24

被引用文献数

3

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The purposes of this study were to classify jumping techniques in the preparatory and take-off phases of elite male long jumpers in official competitions by using a cluster analysis and to identify biomechanical characteristics of classified technique types. The preparatory and take-off motions of 29 elite male long jumpers in official competitions were collected three-dimensionally using two high-speed cameras. Their jumps were classified into four types of jumping technique by using the Ward’s method of cluster analysis with the take-off angle as a parameter. The four types were named the Horizontal (H-type), Semi-Horizontal (SH-type), Semi-Vertical (SV-type), and Vertical (V-type) types. There were no significant differences in jumping distance among the types. H-type jumpers were characterised by a forward lean of the trunk and a larger swing leg knee flexion during the preparatory phase. V-type jumpers flexed the knee joint of the support leg more during support phase in the last stride and showed a larger backward lean of the trunk at touchdown of the take-off foot. SH- and SV-types were located between H-type and V-type jumpers. This classification will help coaches and jumpers to select appropriate techniques.

著者

Yoichi Katsumata

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.201805, (Released:2018-10-18)

参考文献数

17

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This study examined the influence of the relative age effect (RAE) on the competitive level and playing position of male elementary school Japanese baseball players. The sample comprised the following: (1) 506 general male baseball players (BP) who were aged 11–12 (sixth grade) and who had not competed at the prefectural level and (2) 189 regionally selected players (SP) who were aged 11–12 (sixth grade) and who had been selected to compete at the prefectural level or a higher level. The subjects were divided into two groups based on their birth months (Semester 1 (S1): April–September and Semester 2 (S2): October–March). Prevalence ratio for each semester was calculated. Pearson’s chi-square test was employed to examine the RAE of each group and each playing position. Results of a chi-square test at each competitive level showed that the SP group was statistically significant (S1>S2) but the BP group was not. The chi-square test for the pitcher and the fielder (catcher, infielder, and outfielder) positions revealed statistical significance in the SP group (S1>S2), with only the pitcher position showing statistical significance in the BP group (S1>S2). The results indicated that the RAE was higher in more competitive level junior baseball players and that the RAE exerted a stronger influence on the pitcher position than on the fielder positions.

著者

Noriaki Usui Motoki Okumura Kazutoshi Kudo

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.19-26, 2018 (Released:2018-07-24)

参考文献数

18

被引用文献数

2

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To succeed in many sports, players must not only adjust their movements during execution in response to environmental changes, but also switch to different movements altogether. Previous studies have implicated executive functions in movement switching ability. We aimed to clarify expertise differences in movement adjustment and switching, and compared performance on three tasks of target striking between expert and intermediate kendo players as participants. Task 1 was a simple strike, whereby participants struck targets at one position; Task 2 was an adjusted strike, whereby participants struck targets at three positions in a random order. Task 3 was strike-defense switching, whereby participants struck targets as in Task 2 while were also required to switch to defense when an opponent made a counter-strike. That is, the participants were required accurate strike in Task 1 and 2 close to the kendo practices, and were required accurate strike and defense in Task 3 close to the real matches. We found no differences in strike movement time and accuracy in any of the tasks between groups. However, expert players were able to execute successful strike-defense switching in Task 3, whereas intermediate players were not. These results suggest that an expertise difference exists in executive functions, and that it is essential for players to practice focused on acquisition of switching skills in order to further improve their performance.

著者

Mitsumasa Miyashita

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.201733, (Released:2018-02-21)

参考文献数

13

被引用文献数

2

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The purpose of this article was to review the representative research findings on the effects of walking in water on health-related responses from multiple points of view to elucidate the beneficial effects of walking in water on health for older people. Research findings on positive effects of walking exercises in water were identified and discussed in terms of biomechanics, cardiorespiratory responses, body composition, and brain circulation compared with walking exercise on land in young and older adults. Collectively, it was suggested that walking exercise in water would be a recommended form of exercise for older adults, especially with the use of walking poles (i.e. aqua-pole walking).

著者

Natsuki Sado Shinsuke Yoshioka Senshi Fukashiro

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.111-119, 2017 (Released:2018-02-15)

参考文献数

21

被引用文献数

15

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We examine the advantages of a non-orthogonal joint coordinate system (JCS) in calculating each anatomical torque's power through comparison with a segment coordinate system (SCS) of the distal segment. To clarify the differences between coordinate systems, kinematic data were collected from 12 male participants swinging their legs laterally and anteriorly under two conditions: the toe facing forward and facing laterally. The mechanical power and work exerted by each hip anatomical torque in JCS and SCS were calculated. With the toe facing forward, there is no significant difference between the two methods. The largest energy generators were abduction torque for lateral swing and flexion torque for anterior swing. With the toe facing laterally, in JCS, these results were consistent for both lateral swing (abduction: 0.21±0.06 J/kg; flexion: 0.06±0.04 J/kg) and anterior swing (flexion: 0.35±0.09 J/kg; adduction: 0.01±0.01 J/kg). However, in SCS, the largest energy generator for lateral swing changed from abduction (0.08±0.07 J/kg) to flexion torque (0.22±0.12 J/kg). For anterior swing, the hip adduction torque generated as large energy (0.14±0.08 J/kg) as hip flexion torque (0.20±0.08 J/kg) in SCS. Therefore, although SCS resulted in an inconsistency between power generator and movement due to hip external rotation, JCS avoided it, regardless of leg position, allowing JCS to investigate the power generation/absorption of each anatomical torque, particularly during long axial rotation.

著者

Natsuki Sado Shinsuke Yoshioka Senshi Fukashiro

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.201712, (Released:2017-10-11)

参考文献数

21

被引用文献数

15

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We examine the advantages of a non-orthogonal joint coordinate system (JCS) in calculating each anatomical torque's power through comparison with a segment coordinate system (SCS) of the distal segment. To clarify the differences between coordinate systems, kinematic data were collected from 12 male participants swinging their legs laterally and anteriorly under two conditions: the toe facing forward and facing laterally. The mechanical power and work exerted by each hip anatomical torque in JCS and SCS were calculated. With the toe facing forward, there is no significant difference between the two methods. The largest energy generators were abduction torque for lateral swing and flexion torque for anterior swing. With the toe facing laterally, in JCS, these results were consistent for both lateral swing (abduction: 0.21 ± 0.06 J/kg; flexion: 0.06 ± 0.04 J/kg) and anterior swing (flexion: 0.35 ± 0.09 J/kg; adduction: 0.01 ± 0.01 J/kg). However, in SCS, the largest energy generator for lateral swing changed from abduction (0.08 ± 0.07 J/kg) to flexion torque (0.22 ± 0.12 J/kg). For anterior swing, the hip adduction torque generated as large energy (0.14 ± 0.08 J/kg) as hip flexion torque (0.20 ± 0.08 J/kg) in SCS. Therefore, although SCS resulted in an inconsistency between power generator and movement due to hip external rotation, JCS avoided it, regardless of leg position, allowing JCS to investigate the power generation/absorption of each anatomical torque, particularly during long axial rotation.

著者

Yoshikata Morimoto Koji Ito Takashi Kawamura Yukito Muraki

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.1, no.2, pp.238-246, 2003 (Released:2008-01-23)

参考文献数

19

被引用文献数

2 9

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The purpose of this study was to investigate the immediate effects of assisted and resisted training using different weight balls on ball speed and accuracy in baseball pitching. Eight male university baseball players were assigned as subjects. The experiment used a standard 145-gram baseball and two heavier or lighter balls with weights increased or decreased by 10% respectively. The subjects were required to pitch these balls and/or standard ball either six or eighteen times under different training trial conditions: 1) pitching the weighted ball only, 2) pitching the lightened ball only, 3) pitching the standard ball only, and 4) pitching three kinds of balls in order of the weighted, standard and lightened balls. Immediately after each training trial, the standard ball was pitched five times respectively (test trial). The ball speed of each trial was measured with a speed gun, and the distance from the center of target to the position of the ball pitched on the target was calculated using a video digitizing system. The results are summarized as follows: 1) In the training trials, the ball speed increased as the ball weight was decreased. 2) In the test trials, immediately after pitching the lightened ball both six (6Atest) and eighteen times (18Atest), and the three different kinds of balls eighteen times (18Ctest), the ball speeds were seen to be significantly higher than that of other test trials (p<0.01). 3) Although there were no significant differences in the ball speed in the above three test trials, a relatively higher ball speed was observed in 18Atest. 4) As for the distance from the center of target to the position of the ball pitched on the target, there were no significant differences among any trials.

著者

Naoki MURASE Gen HORIUCHI Katsuhiro SUMI Kenji HORIYAMA Sinji SAKURAI

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.201611, (Released:2017-05-12)

参考文献数

14

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The objectives of the present study were: to examine the relationship between kendo competition levels and men strike times in 20 university kendo club members; and to determine factors for shortening men strike times. LED lamps were attached to the men and the kote (the strike targets), and subjects struck in the direction of the lit LED lamp with maximal effort from a distance of 2.30 m. Phase times, movements, and ground reaction force on both feet were analyzed. The results were as follows. 1. Subjects of higher competition levels tended to demonstrate shorter men strike times. Reaction times, movement times, and shinai upswing phase time also tended to be shorter. 2. Factor for shortening men strike times in the upswing phase consisted of the following: lifting the right foot from the ground quickly, simultaneously pushing off the ground with great force with the left foot, quickly lifting the right thigh forward while moving the body forward, and to increase the range of upswing motion of the shinai with high velocity. In the downswing phase, the shinai should be swung at a higher velocity, and the left shoulder should be flexed more when striking.

著者

Yoshiyuki Saito Sunao Uchida Yoshiko Yabe Makoto Miyazaki

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.1-5, 2017 (Released:2017-04-18)

参考文献数

5

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Psychological studies have shown that when individuals move their gaze between two alternative objects, they tend to choose the object that holds their gaze for longer (the gaze-manipulation effect). This effect is especially evident when both alternatives appeal to the viewer. We hypothesized that if individuals have an interest in sports and/or fashion, and thus view varieties of sportswear favorably, then gaze manipulation would influence their choice. Japanese university students participated in our experiments. The participants made preference choices between two uniforms of European football teams, which were presented alternately across the left and right sides of a computer screen six times for different durations (900 ms vs. 300 ms). They were required to compare the uniforms with or without fixing their gaze directly on them. They also completed questionnaires designed to assess their interest in football and fashion. The results showed that the gaze-manipulation effect was not significant across all participants or across those participants who merely liked fashion, or who merely watched football or casually played it. However, the effect was significant in participants who had been members of football teams. Our results suggest that application of the gaze-manipulation technique would be more effective for visual advertisement of sports items if it was focused on sports players.

著者

Ryoji Toyoshima Shinji Sakurai

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.14, pp.41-50, 2016 (Released:2016-09-30)

参考文献数

26

被引用文献数

6

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The present study aimed to clarify kinematics among sprinters with similar step length but different step frequencies, and with similar step frequencies but different step lengths in sprinting. We collected kinematic data from 54 sprinters at approximately the 60 m point of a 100-m sprint using a high-speed camera. The sprinters within 0.5SD from the mean value of each of step frequency and length at top speed phase were included in the ‘SL-similar’ (n=22, step frequency: 3.99-5.19 Hz, step length: 2.07-2.15 m) and the ‘SF-similar’ (n=22, step frequency: 4.51-4.72 Hz, step length: 1.93-2.33 m) groups, respectively. In the SL-similar group, higher step frequency was correlated with shorter stance time (r=−0.899), and a more vertical thigh angle at take-off (r=0.623). In the SF-similar group, longer step length was correlated with greater distance of the hip during flight phase (r=0.847), and a larger vertical acceleration of the forward swinging leg relative to the hip (r=0.438). In conclusion, leg kinematics at touchdown and take-off are important for high step frequency in similar step length, and forward swinging leg kinematics are important for long step length in similar step frequency.

著者

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

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, pp.10-18, 2006 (Released:2008-01-25)

参考文献数

26

被引用文献数

1 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

Kazunori Nosaka Andrew Lavender Mike Newton Paul Sacco

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.1, no.1, pp.1-8, 2003 (Released:2008-01-23)

参考文献数

29

被引用文献数

8 32

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The objectives of this review are to delineate muscle damage induced in resistance training, discuss how muscle damage is associated with increases in strength and/or muscle cross-sectional area, and clarify whether “pain” is necessary for “gain” in muscle function and muscle volume in resistance training. Resistance training induces muscle damage, especially in the initial phase of training when unaccustomed eccentric actions are performed. Muscle damage is best indicated by loss of muscle strength and range of motion, and delayed onset muscle soreness does not necessarily reflect the magnitude of muscle damage. Resistance training employing eccentric biased exercises has potential for increasing not only eccentric strength but also isometric strength, and seems to be superior to exercise based solely on concentric actions. Since muscle damage and soreness are induced to a greater extent in eccentric muscle actions than with isometric or concentric actions, it is believed that muscle damage is necessary for size and strength gain. However, it appears that muscles become less susceptible to muscle damage as training progresses. We concluded that muscle damage and/or muscle soreness are not necessarily indispensable for exercise-induced muscle adaptation.

著者

Seshito Shimizu Kohei Shimamoto 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.201411, (Released:2015-02-24)

参考文献数

18

被引用文献数

3 6

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The purpose of this study was to investigate the relationships between life skills and post-graduation employment for top college student athletes. In March 2011, 24 Japanese top level male wrestlers (mean age=22.0±0.2) who had graduated from university in March 2011 answered to the Appraisal Scale of Required Life Skills for College Student Athletes (Shimamoto et al., 2013). This scale has following 10 subscales: stress management, setting goals, thinking carefully, appreciating others, communicating, maintaining etiquette and manners, always making one's best effort, taking responsibility for one's own behavior, being humble, and maintaining physical health and well-being. The relationships between life skills acquisition level assessed in March 2011 and employment situations (employed or unemployed) by March 2012 were examined with nine members who had not obtained employment by the time of graduation from university. The analysis results showed that the employment group (n=4) who had acquired employment within one year of graduation indicated a higher acquisition level compared to the unemployed group (n=5) with regard to setting goals (p<.05). Therefore, it was suggested that there is the positive relationship between setting goals and post-graduation employment for top college student wrestlers.

著者

Kenji Doma Glen Bede Deakin

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.11, pp.1-9, 2013 (Released:2013-03-28)

参考文献数

27

被引用文献数

2 13

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This study examined running economy (RE) during a two-stage incremental protocol that was combined into an endurance training session 6 hours following a strength training session. In addition, this study investigated running performance which consisted of a two-stage RE protocol and time to exhaustion (TTE) the day after strength and endurance training sessions undertaken on the same day. Twelve trained and moderately trained male runners performed strength and endurance training sessions 6 hours apart with running performance tests conducted the following day. Cost of running (CR) and rate of perceived exertion (RPE) were collected during the endurance training session whereas CR, RPE and TTE were collected during the running performance test. Maximal voluntary contraction (MVC) tests were conducted prior to and following the strength and endurance training sessions and the running performance tests. The results showed that CR significantly increased during the second stage of the endurance training session (p<0.05). During the running performance test, significant increases were found for CR during the first and second stages and for RPE during the second and third stages (p<0.05). The MVC was significantly reduced immediately following the strength training sessions, pre-post the endurance training session, and running performance test (p<0.05). The findings in the current study show that RE is impaired 6 hours following a strength training session. Furthermore, combined strength and endurance training on the same day appears to cause an accumulation effect of fatigue which impairs running performance the following day.

著者

Kazushige Goto Naokata Ishii Kaoru Takamatsu

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.2, pp.111-118, 2004 (Released:2008-01-23)

参考文献数

25

被引用文献数

3 4 6

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We had previously shown that performing a single set of resistance exercise at 50% of 1 repetition maximum (RM) added after a high-intensity, low-repetition exercise (strength-type regimen) greatly enhanced growth hormone (GH) secretion [Goto et al. (2003)]. The present study aimed to investigate the effect of an additional set at 50% to 20% of 1RM after a strength-type regimen on anabolic hormone secretion. Eight male subjects performed bilateral knee extension exercises using a strength-type regimen (5 sets at 90% of 1RM, with 3-min rests), and other 3 types of regimens, in which 1 set of exercise at either 50%, 30% or 20% of 1RM was added immediately after the strength-type regimen (defined as C50-type, C30-type and C20-type regimens, respectively). Concentrations of serum GH, testosterone and blood lactate were measured before and after exercises. The number of repetitions in the added set showed a significant dependence on the exercise intensity: 82.3 times in C20-type > 46.1 times in C30-type > 22.6 times in C50-type (p ≤ 0.05). Post-exercise GH concentrations were significantly (p ≤ 0.05) higher in C50- and C30-type regimens than in the strength-type regimen, whereas no significant difference was observed between C20- and strength-type regimens. Testosterone did not change in any types of regimen. These results indicated that performing a single set of exercise at low intensity added after a strength-type regimen caused a significant increase in GH concentration. However, such an effect might be diminished when the intensity of the additional exercise was extremely low (below 20% of 1RM).