著者

那須 大毅 松尾 知之

出版者

バイオメカニズム学会

雑誌

バイオメカニズム (ISSN:13487116)

巻号頁・発行日

vol.22, pp.69-78, 2014 (Released:2017-02-15)

参考文献数

17

被引用文献数

1

---

本研究では, ダーツ投げ動作の鉛直面におけるリリース変数 (リリース時のダーツ位置, 投射速度, 投射角) に着目し, 1) 各リリース変数のばらつきの大きさ, 2) リリース変数間の相互補完構造の度合いに関して, 熟練者 (8名) と初心者 (8名) の違いについて検討した. 各被験者は60投のダーツ投げ動作を実施し, ダーツおよび人差し指の動作を7台の赤外線カメラ (480Hz) で撮影, 座標データを取得した. 分析の結果, パフォーマンス結果のばらつきが小さかった熟練者は初心者と比べて, 1) 全てのリリース変数のばらつきが小さく, 2) リリース変数間の相補構造の度合いも大きかった. ただし一部の熟練者は, 影響が最も強い投射角のばらつきを非常に小さくすることで, パフォーマンス結果のばらつきを小さくしていた.

著者

那須 大毅 松尾 知之

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.14047, (Released:2015-01-20)

参考文献数

12

---

The aim of the present study was to investigate the differences in kinematics between two types of motor strategy for expert dart throwing. We divided eight experts into two groups based on the motor strategies they had demonstrated in a previous study (Nasu et al., 2014): group A were experts who had a longer time window in which a release could result in hitting the bull's eye, and group B were experts who had a shorter time window but greatly reduced their timing error. Each subject performed 60 dart throws, aiming at the center of the dart board (bull's eye). The movement of the dart, index finger, and joint motion of the upper extremity were captured using a motion capture system with 7 cameras (480 Hz, Oqus300, Qualysis Inc.). We compared the shape of the hand trajectory and joint kinematics between the groups. We found that experts in group A demonstrated a smaller shoulder angle (lower elbow height) and a larger angle of elbow flexion through forward swing than those in group B. These differences affected the time window that led to a successful throw, i.e. the time for which the mutually complementary relationship among the release parameters (especially the relationship between velocity and direction of motion) was maintained. These results may be useful as basic data to help clarify how throwing accuracy can be improved in several sports.

著者

松尾 知之 平野 裕一 川村 卓

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.55, no.2, pp.343-362, 2010 (Released:2010-12-28)

参考文献数

43

被引用文献数

4 2

---

The purposes of this study were to elicit experiential knowledge from expert baseball pitchers and baseball coaches, to elucidate key coaching points related to movement in baseball pitching, to classify them into categories, and to investigate any commonality among them. Semi-structured interviews were conducted with four former Japanese professional baseball pitchers and seven expert high-performance (national level) Japanese baseball coaches. Each interviewee was requested to comment on the pitching of 25 amateur baseball pitchers (11 junior high school, 8 high school, and 6 collegiate baseball pitchers), which had been videotaped beforehand. The comments were recorded, dictated literally, and divided into segments on the basis of meaning unit. Based on the properties of the various meaning units, some were gathered and classified into categories. For this process, we conducted a member check and triangulation to improve reliability and validity. We extracted 3283 units and classified them into 14 general categories and 71 specific categories. The most frequent category was “trunk open and quick turn during the stride and arm cocking phases”. However, this accounted for only 5.5% of the total meaning units. The next most frequent categories were “weighting on the pivot foot in the balanced position and during the stride phase” (4.7%) and “the throwing arm movement during the stride phase” (4.6%). The contents of all categories covered various aspects of movement. Among the relatively frequent categories, a few elicited the same opinion among the interviewees, but some had different opinions even about the same pitcher. These results suggest that there is a diversity of coaching points among coaches, and that it is important to know the categories that are determinative and those that should be chosen selectively.

著者

那須 大毅 松尾 知之

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.303-313, 2015 (Released:2015-06-13)

参考文献数

12

---

The aim of the present study was to investigate the differences in kinematics between 2 types of motor strategy for expert dart throwing. We divided 8 experts into 2 groups based on the motor strategies they had demonstrated in a previous study (Nasu et al., 2014): group A were experts who had a longer time window in which a release could result in hitting the bull's eye, and group B were experts who had a shorter time window but greatly reduced their timing error. Each subject performed 60 dart throws, aiming at the center of the dart board (bull's eye). The movement of the dart, index finger, and joint motion of the upper extremity were captured using a motion capture system with 7 cameras (480 Hz, Oqus300, Qualysis Inc.). We compared the shape of the hand trajectory and joint kinematics between the groups. We found that experts in group A demonstrated a smaller shoulder angle (lower elbow height) and a larger angle of elbow flexion through forward swing than those in group B. These differences affected the time window that led to a successful throw, i.e. the time for which the mutually complementary relationship among the release parameters (especially the relationship between velocity and direction of motion) was maintained. These results may be useful as basic data to help clarify how throwing accuracy can be improved in several sports.

著者

松尾 知之

出版者

大阪大学

雑誌

挑戦的萌芽研究

巻号頁・発行日

2016-04-01

---

本研究では、これまで困難とされてきた投球動作中の肩甲骨の動きを計測することを可能とした。複数肢位のキャリブレーション姿勢において、肩甲骨体表部に半径3mm の小型反射マーカーを2.5cm間隔で8行7列貼付し、その凹凸や角度、高さ情報から重回帰分析によって数学モデルを生成した。従来型のマーカークラスター法(AMC法)と比較すると、AMC法ではリリース付近で明らかなノイズが出現したが、そのノイズは消失しており、投球全域に亘って計測可能なことが確認された。この肩甲骨可動モデルをつかって、キネマティクスの算出を試みた結果、肩関節のnet forceのピーク値は、むしろ増加したことが明らかとなった。

著者

斎藤 健治 松尾 知之 宮崎 光次

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.51, no.3, pp.351-365, 2006 (Released:2008-01-25)

参考文献数

26

被引用文献数

1

---

In order to investigate muscle activity during overhand baseball pitching, surface EMG analysis of muscles in the shoulder girdle and upper limb was performed. The subjects were two college baseball players. Surface EMG was recorded from 25 portions of 16 muscles: the long and short head of the biceps brachii, the coracobrachialis, the brachialis, the lateral, medial and long head of the triceps brachii, the anterior, middle and posterior deltoid, the sternocostalis of the pectoralis major, the latissimus dorsi, the upper, middle and lower trapezius, three portions of the serratus anterior, the pronator teres, the flexor carpi radialis, the flexor carpi ulnalis, the extensor carpi radialis, the extensor digitorum, the extensor carpi ulnalis, and the brachioradialis. After rectifying the surface EMGs, their linear envelopes were extracted with a digital low-pass filter. The duration, timing and similarity of these muscle activities before and after ball-release were analyzed quantitatively through auto-correlation and cross-correlation analysis of the envelopes. The biceps and the brachialis were activated in the cocking phase and follow-through phase, and played a role in preparing for acceleration and deceleration in each phase. The triceps was activated in the acceleration phase and elbow joint extension, and contributed to the increase of ball speed by minimizing the moment of inertia about the longitudinal axis of the upper limb. The coracobrachialis was activated from the cocking phase until ball-release, and contributed to the horizontal extension of the shoulder joint. The latissimus dorsi and the pectoralis major were activated in the acceleration phase, and the duration of their activity was shorter than that of the other muscles. The activities of the trapezius and the serratus anterior differed between the two subjects. These activities in one subject were simultaneous in the acceleration phase, and those in the other were separate in the cocking phase. These activities probably represent differences in the control of scapula motion during pitching. The peak activities of the forearm muscles were concentrated in the ball-release phase, and the duration of activity was longer in the extensor muscles than in the flexor muscles. This type of correlation analysis is useful for extracting information about muscle activity during baseball pitching.

著者

松尾 知之 平野 裕一 川村 卓

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.58, no.1, pp.195-210, 2013 (Released:2013-06-08)

参考文献数

18

---

Expert players and/or expert coaches have a large stock of experiential knowledge, including knowledge of movement-related causality. We attempted to extract experiential knowledge of movement-related causality in baseball pitching from expert players and coaches with sufficient creditability. Verbal data collected in a previous study (Matsuo et al. 2010) using semi-structured interviews with four former professional baseball pitchers and seven expert baseball coaches were used for this study. The data had been categorized on the basis of a wide variety of coaching points. A matrix of co-occurrence based on the verbal data was used to calculate the strength of association between pairs of categories. In the process of the calculation, we employed the matrix calculation utilized in the Dematel method to count indirect associations. The distances among categories, calculated on the basis of co-occurrence probability, were used to assess the creditability of the verbal data. The categories were mapped into three-dimensional space using the least squares method, based on the distances. The associations of categories were extracted as highly trustworthy when the root mean squared error between the original distances and the mapped distances was below 10%. Among the extracted associations, the direction of causality was added to the associations that expressed the causality explicitly among the verbal data. The major selected causalities were as follows:1)  Moving forward before placing weight on the pivot foot sufficiently opens the trunk earlier and leads to insufficient weight being placed on the stride foot.2)  An inadequate take-back action, especially excessive horizontal abduction and elbow extension, limits the flexible arm movement around throwing-side ear and leads to lower shoulder abduction. In addition, it makes the trunk open earlier.3)  Excessive lead elbow extension during the stride phase makes the trunk open earlier. How the lead-arm is pulled towards the trunk also affects trunk rotation.4)  Bending the neck at any point leads to inadequate trunk rotation.

著者

松尾 知之 松尾 知之

出版者

大阪大学

雑誌

基盤研究(C)

巻号頁・発行日

2006

---

新しいタイプの指導者支援システムを構築するための基礎資料を得ることを目的とし, 経験豊富な運動指導者の培った経験知を体系的に調査・抽出した. 特に, 本研究では野球の投球動作指導に焦点をあてた. 熟練指導者等への面接調査によって, 投球動作の指導内容について, 飽和状態に達したと考えられる段階まで知識を抽出できた. また, 心理実験やアンケート調査により, 指導者間で共通性のある項目と共通性に乏しい項目を明らかにするとともに選好度の高い投球動作をCGで表すことが可能となった.

著者

橋詰 謙 松尾 知之 門田 浩二

出版者

バイオメカニズム学会

雑誌

バイオメカニズム学術講演会予稿集

巻号頁・発行日

vol.23, pp.83-86, 2002-10-26