著者

夏原 隆之 中山 雅雄 加藤 貴昭 永野 智久 吉田 拓矢 佐々木 亮太 浅井 武

出版者

一般社団法人 日本体育学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

vol.60, no.1, pp.71-85, 2015 (Released:2015-06-13)

参考文献数

31

被引用文献数

4 3

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Some of the mechanisms underlying superior performance in sports may be clarified by investigating the role of visual information in the execution of particular responses by expert athletes. The aim of this study was to examine how soccer players process visual information when executing a tactical pass in a 4 vs. 4 attacking play scenario. To identify the cognitive processes operating during task execution, we measured eye movement and correlated it with verbal reports from players. The subjects comprised 30 soccer players with differing proficiencies (15 “experts” and 15 “sub-experts”). 2 tests were carried out: a test to evaluate the level of passing skill, and a decision-making test to evaluate the reproducibility of tactical passing and the accuracy of passes aimed to specific locations. Eye movements were measured during the decision-making test. Furthermore, in each trial of the decision-making test, verbal reports were collected. These related to how and why participants decided to pass the ball to any particular player among the 4 attackers on screen and, in order to determine their best judgment, how they captured the play situation and what they paid attention to. The results revealed that for execution of the pass, the experts were significantly more proficient at passing accurately to the aimed location, and their passing judgment was more reproducible in comparison to the sub-experts, although both groups had a uniform level of passing skill in terms of pass execution. In addition, eye movement data obtained during pass execution confirmed that in the play observation phase, while experts maintained their line of sight on other objects, they also maintained a longer gaze on defensive players to identify gaps between them. Also in the ball approach phase, the experts maintained a longer gaze on the player who was judged to be the best choice for receiving an accurate pass. These observations suggest that the superior passing performance of expert soccer players is attributable to accurate and efficient extraction of visual information and utilizing it in the context of their accumulated knowledge base.

著者

太田 和希 吉田 拓矢 小野 響也 前村 公彦 谷川 聡

出版者

一般社団法人 日本体育・スポーツ・健康学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

vol.67, pp.793-808, 2022 (Released:2022-09-29)

参考文献数

38

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This study investigated the relationships between pelvic behavior and impulse of ground reaction force as well as leg backward swing velocity during the acceleration phase and full speed phase of sprint running. Eleven male sprinters performed 30-m and 60-m sprints from a crouching start at maximal effort. Threedimensional motion analysis was performed to investigate the relationships between pelvic behavior and impulse of ground reaction force as well as leg backward swing velocity during the acceleration phase and full speed phase of sprinting running. The angular displacement of the pelvic free leg side lateral flexion in the frontal plane showed a significant positive correlation with the propulsion and vertical impulse during the acceleration phase. Also, the lumbosacral free leg side lateral flexion angular impulse showed a significant positive correlation with the propulsion and vertical impulse during the acceleration phase. Additionally, the lumbosacral free leg side torsion angular impulse showed a significant positive correlation with the peak value of the free leg backward swing velocity during the full speed phase. Therefore, the results obtained during the acceleration phase suggest that the pelvic free leg side lateral flexion was able to increase the propulsion and vertical impulse, whereas during the full speed phase, the pelvic free leg side rotation contributed to increasing the free leg backward swing velocity.

著者

吉田 拓矢

出版者

日本時間学会

雑誌

時間学研究 (ISSN:18820093)

巻号頁・発行日

vol.11, pp.19-34, 2020 (Released:2021-06-14)

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古代日本においては、日蝕を忌避することに昼夜は関係しない、という時間観念があった。日没のため実際に観測できない場合であっても、日蝕とみなされて朝廷政務は止められたのである。つまり、日蝕記事のなかに日本から観測可能であったものが少ないのは、暦官らが誤算を犯したからではなく、はじめから観測できることを想定していないものまで「夜蝕」として予報していたからであった。 このことを踏まえて記事を分析していくと、10世紀までの日蝕予報と暦官らの技能は、次のようにまとめられる。8世紀から9世紀中葉にかけては、予報に誤算がみられないことから、ときの暦官らは的確に計算を進められるだけの技能を有していたことがわかる。しかし宣明暦施行後は、日本に伝えられた暦本に漏れがあったことも影響し、的中率が大幅に低下した。このときに予報精度をしばらく改善することができなかったのは、唐から伝えられた暦術をひたすら墨守しようとする、彼らの姿勢の表れであろう。

著者

吉田 拓矢 川原 布紗子 福田 有紗 白井 蒼 佐久間 彩 図子 あまね 淺井 武 谷川 聡 平嶋 裕輔

出版者

一般社団法人 日本体育・スポーツ・健康学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

pp.20110, (Released:2021-05-12)

被引用文献数

1

著者

川原 布紗子 吉田 拓矢 野中 愛里 谷川 聡

出版者

一般社団法人 日本体育・スポーツ・健康学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

vol.66, pp.77-90, 2021 (Released:2021-02-13)

参考文献数

35

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The purpose of this study was to examine the effect of decision making under a light stimulus on movement during a change of direction (COD). Twelve male soccer players performed 2 types of lightbased backward agility test (BAT): normal condition and pre-planned condition (BAT-PP). Their motions were videotaped using 2 high-speed cameras operating at 300 Hz for three-dimensional motion analysis. The time, step parameter, and each kinematic variable were compared to determine the differences between the BAT and BATPP. The results showed that the times for 5–13 m and 0–13 m in the BAT were slower than those in the BAT-PP. The velocity of the center of gravity at the lowest point of the velocity in the BAT was lower than that in the BATPP. During the pre-COD phase, the body inward lean angle, shoulder rotation angle, and pelvis rotation angle were all smaller in the BAT than in the BAT-PP. At the COD foot contact, foot placement in the left-right direction was shorter and knee flexion was greater in the BAT than in the BAT-PP. Furthermore, hip flexion during the deceleration phase, and shoulder and pelvis rotation during the acceleration phase were larger in the BAT than in the BAT-PP. Overall, these results may indicate that players who performed the BAT were required to maintain a posture that allowed them to turn to the left or right until the presentation of the light stimulus; therefore, their bodies were upright, and their trunks were facing the direction of approach before COD. Moreover, the knee joint flexed with a short distance to the left of the COD foot placement, the velocity of the center of gravity decreased with hip flexion, and the trunk rotated significantly to a new direction in the BAT.

著者

林 陵平 苅山 靖 吉田 拓矢 図子 浩二

出版者

一般社団法人 日本体育・スポーツ・健康学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

vol.61, no.2, pp.575-587, 2016 (Released:2016-12-14)

参考文献数

26

被引用文献数

3

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The purpose of this study was to identify the ground reaction force and joint kinetics in the lower extremity during the catch phase of the clean exercise through comparison with the pull phase. Eleven male track and field athletes performed the power clean from the floor with loads of 30%, 60%, and 90% of 1RM (One Repetition Maximum). Kinetic data were collected from data recorded using a Vicon motion system (250 Hz) and force platforms (1,000 Hz). The results of the analyses were as follows:  1) In the catch phase, force development was similar to that of the pull phase because the peak ground reaction force was not significant during the 2 phases.  2) The joint kinetics in the ankle and knee joints were larger during the catch phase than during the pull phase.  3) During the power clean, force development was achieved mainly by concentric muscle contraction during the pull phase and by eccentric muscle contraction during the catch phase.  4) The ground reaction force and joint kinetics were significantly different during the catch phase.  These results show the differences in load characteristics in the lower extremity between the pull and catch phases during clean exercise. Therefore, not only the pull phase but also the catch phase should be considered when performing the clean exercise in weight training.

著者

高橋 和孝 篠原 秀典 吉田 拓矢 浅井 武

出版者

一般社団法人 日本体育・スポーツ・健康学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

pp.20076, (Released:2021-04-06)

著者

吉田 拓矢 松島 一司 林 陵平 図子 あまね 苅山 靖

出版者

一般社団法人 日本体育学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

pp.17129, (Released:2018-08-06)

参考文献数

37

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The purpose of this study was to evaluate the multistep drop jump (DJ) test in elite jumpers according to changes in test performance, ground reaction force, and lower limb joint kinetics with changes in drop height. Male jumpers (n=10) performed a DJ from 4 drop heights (0.3, 0.6, 0.9, and 1.2 m). The DJ-index was calculated by dividing the jump height by the contact time. The rate of change of the DJ-index (a/b) was the slope/intercept of the regression line (Y = aX+ b) derived from 4 values of the DJ-index for each subject. Jump motions in the sagittal plane and ground reaction force data were recorded using a high-speed camera and force platform, respectively. The DJ-index was lower at 1.2 m than at other drop heights. The contact time increased along with the drop height. There was no significant difference in jump height between the drop heights. The amount of negative work by 3 lower extremity joints increased with increasing drop height. The jump events performance (IAAF Score) and DJ-index at each drop height only showed a significant correlation at 1.2 m. The correlation between IAAF score and a/b was significant between these variables. According to individual characteristics, increased drop heights were associated with different patterns of change in the DJ index. Therefore, subjects were grouped according to characteristics using a/b as an index. Sub.A, who had the highest jump-event performance in the study, had participated in international meetings, and had won a medal at the World Junior Championships. The DJ-index for this subject at 0.3 m was close to the mean value, but at 1.2 m was highest among all the subjects. In contrast, the DJ-index for Sub.C at 0.3 m was highest among the subjects. However, the DJ-index decreased greatly with an increase from 0.3 m to 1.2 m. Therefore, to evaluate the performance of jumpers, it is important to use a varied range of heights, including a higher drop height (approximately 1.2 m), focusing on the rate of change with increasing drop height.

著者

苅山 靖 林 陵平 吉田 拓矢 図子 あまね 図子 浩太佑 図子 浩二

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.67, no.2, pp.187-197, 2018-04-01 (Released:2018-03-16)

参考文献数

44

被引用文献数

1

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Movement control and muscle function for pelvic movement in the frontal plane (pelvic elevation) are important for various single-leg sports activities. We aimed to clarify mechanical characteristics of pelvic squat (P-Sq: single-leg squat exercise with emphasis on pelvic elevation, developed by our research group) compared with the double-leg squat (D-Sq) and single-leg squat (S-Sq). Twelve male track and field athletes performed D-Sq, S-Sq, and P-Sq exercises at various loads (90%, 75%, and 60% of 1-repetition maximum [1RM]), using maximum effort. Kinematic and kinetic data were calculated using data recorded with a motion capture system and force platforms. We observed the highest values with P-Sq, followed by S-Sq and D-Sq under all load conditions as follows: peak vertical ground reaction force and rate of force development (RFD), range of pelvic elevation, peak pelvic elevation velocity, peak powers associated with hip abduction torque and trunk lateral flexion torque. In P-Sq, RFD at 90% 1RM was smaller than under the other load conditions, whereas peak vertical ground reaction force at 90% 1RM was larger than under the other load conditions. There were no differences among load conditions with regard to hip abduction and trunk lateral flexion torques and powers. Therefore, characteristics of P-Sq compared to those of D-Sq and S-Sq are 1) larger and faster pelvic elevation, using related muscles (hip abductors and trunk lateral flexors) under all load conditions, 2) larger peak ground reaction force with pelvic elevation under large load conditions, and larger RFD in pelvic elevation under low load conditions.

著者

林 陵平 苅山 靖 吉田 拓矢 図子 浩二

出版者

一般社団法人 日本体育学会

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

pp.15101, (Released:2016-08-19)

参考文献数

26

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The purpose of this study was to identify the ground reaction force and joint kinetics in the lower extremity during the catch phase of the clean exercise through comparison with the pull phase. Eleven male track and field athletes performed the power clean from the floor with loads of 30%, 60%, and 90% of 1RM (One Repetition Maximum). Kinetic data were collected from data recorded using a Vicon motion system (250 Hz) and force platforms (1,000 Hz). The results of the analyses were as follows:  1) In the catch phase, force development was similar to that of the pull phase because the peak ground reaction force was not significant during the two phases.  2) The joint kinetics in the ankle and knee joints were larger during the catch phase than during the pull phase.  3) During the power clean, force development was achieved mainly by concentric muscle contraction during the pull phase and by eccentric muscle contraction during the catch phase.  4) The ground reaction force and joint kinetics were significantly different during the catch phase.  These results show the differences in load characteristics in the lower extremity between the pull and catch phases during clean exercise. Therefore, not only the pull phase but also the catch phase should be considered when performing the clean exercise in weight training.

著者

栗原 哲彦 吉田 拓矢 榎本 太一 甲賀 覚

出版者

一般社団法人 セメント協会

雑誌

セメント・コンクリート論文集 (ISSN:09163182)

巻号頁・発行日

vol.73, no.1, pp.340-347, 2020-03-31 (Released:2020-03-31)

参考文献数

11

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化学目粗し法により打ち継いだ付着部は母材で破壊が生じるほどの付着強度を発揮し、NEXCO「構造物施工管理要領」の規定値1.5N/mm2を上回ることが分かった。また、母材が普通コンクリートであれば、ブラスト処理面より化学的目粗した粗面のせん断強度の方が大きくなった。これより従来工法であるブラスト処理と同程度の付着特性を発揮することが分かった。付着面の付着強度ならびにせん断強度と表面粗さとの関係については、RzJISとともにSpcも評価指標に加えて用いる方がより的確な評価が可能になることが分かった。

著者

太田 和希 九鬼 靖太 奥平 柾道 吉田 拓矢 前村 公彦 谷川 聡

出版者

The Japan Journal of Coaching Studies

雑誌

コーチング学研究 (ISSN:21851646)

巻号頁・発行日

vol.33, no.2, pp.145-159, 2020-03-20 (Released:2020-06-11)

参考文献数

38

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This study aimed to clarify the step variables and three-dimensional joint kinematics of the pelvis while increasing running speed on a treadmill. Sixteen male track and field athletes ran on an instrumented treadmill at three different running speeds: 4.0, 6.0, and 8.0 m/s. The step variables, such as step frequency, step length, contact time, and flight time, and the kinematic data of each running speed were recorded using a high-speed video camera (300 fps) and a Vicon T20 system (250 Hz). In addition, the pelvic angular displacement (Δ) was calculated by subtracting the minimum from the maximum values of the pelvic angle in the stance phase. The results were as follows: (1) Stride length and step frequency were significantly greater at higher running speeds. Although contact time was significantly shorter at the faster speeds, flight time was significantly shorter when transitioning from 6.0 to 8.0 m/s and from 4.0 to 8.0 m/s. (2) The pelvis of the swing leg side elevated from toe off to early half of swing phase with increasing running speeds. In addition, the pelvis of the stance leg side rotated to the swing leg side from mid stance phase to toe off with increasing running speeds. (3) Δelevation showed a significant negative correlation with step frequency but a significant positive correlation with stride length for each running speed. In addition, Δrotation showed a significant positive correlation with step frequency but a significant negative correlation with stride length at 8.0 m/s.     Therefore, increased pelvic elevation improves the stride when transitioning from a low to high speed, and increased pelvic rotation leads to a higher step frequency during the stance phase when running at 8.0 m/s. In addition, it was suggested that it is necessary to run at minimum 8.0 m/s for the pelvis to behave differently compared with running at slower speeds to learn the high speed running movement.

著者

苅山 靖 林 陵平 吉田 拓矢 図子 あまね 図子 浩太佑 図子 浩二

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.67, no.2, pp.187-197, 2018

被引用文献数

1

---

<p>Movement control and muscle function for pelvic movement in the frontal plane (pelvic elevation) are important for various single-leg sports activities. We aimed to clarify mechanical characteristics of pelvic squat (P-Sq: single-leg squat exercise with emphasis on pelvic elevation, developed by our research group) compared with the double-leg squat (D-Sq) and single-leg squat (S-Sq). Twelve male track and field athletes performed D-Sq, S-Sq, and P-Sq exercises at various loads (90%, 75%, and 60% of 1-repetition maximum [1RM]), using maximum effort. Kinematic and kinetic data were calculated using data recorded with a motion capture system and force platforms. We observed the highest values with P-Sq, followed by S-Sq and D-Sq under all load conditions as follows: peak vertical ground reaction force and rate of force development (RFD), range of pelvic elevation, peak pelvic elevation velocity, peak powers associated with hip abduction torque and trunk lateral flexion torque. In P-Sq, RFD at 90% 1RM was smaller than under the other load conditions, whereas peak vertical ground reaction force at 90% 1RM was larger than under the other load conditions. There were no differences among load conditions with regard to hip abduction and trunk lateral flexion torques and powers. Therefore, characteristics of P-Sq compared to those of D-Sq and S-Sq are 1) larger and faster pelvic elevation, using related muscles (hip abductors and trunk lateral flexors) under all load conditions, 2) larger peak ground reaction force with pelvic elevation under large load conditions, and larger RFD in pelvic elevation under low load conditions.</p>

著者

川原 布紗子 吉田 拓矢 野中 愛里 谷川 聡

出版者

一般社団法人 日本体育学会

雑誌

日本体育学会大会予稿集

巻号頁・発行日

vol.70, pp.253_3, 2019

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<p> 本研究は、状況判断の有無による方向転換動作への影響を明らかにすることを目的とした。男子大学サッカー選手12名を対象とし、状況判断を伴った方向転換走 (RAT) およびRATと同様の走路における状況判断を伴わない方向転換走(CODT) を実施し、タイムおよび方向転換前後1歩ずつにおけるキネマティクスを検討した。タイムは方向転換を含む5-13m区間において、CODTがRATよりも有意に早かった。身体重心速度は、身体重心速度最下時点においてCODTが有意に高かった。身体傾斜角度においては、矢状面で差が認められなかった一方で、前額面においてCODTは方向転換前に有意に内傾していた。これらの結果は、CODTは前後方向にはRATと同様の傾きを保持しながら、方向転換前に内傾することで高い速度を維持した減速が可能であったと考えられる。また、股関節では、身体重心速度最下時点においてCODTが有意に伸展位であった。加えて、方向転換足接地時点から身体重心速度最下時点までの股関節角度の変位量においてCODTでは伸展量が大きかった一方で、RATでは屈曲量が大きい結果となった。これらの結果は、状況判断を伴うことで減速における下肢関節の働きが異なる可能性が示唆された。</p>