著者
蔭山 雅洋 鈴木 智晴 藤井 雅文 中本 浩揮 和田 智仁 前田 明
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.61, no.2, pp.517-535, 2016 (Released:2016-12-14)
参考文献数
37
被引用文献数
2 1

The purpose of this study was to clarify the profiles of lower limb and trunk motion during baseball pitching in relation to differences between the mound and the flat ground, and to determine the motion characteristics while pitching from the 2 locations.  The subjects were 12 baseball pitchers (age 18.6±2.5 yr, height 173.4±6.5 cm, weight 74.7±11.0 kg) who belonged to high school or university baseball teams. Three-dimensional positions of 36 reflective markers attached to each subject were tracked by an optical motion capture system (Mac3D System) with 12 cameras. The ground-reaction forces (GRF) of the pivot and stride legs during pitching were determined using 2 multicomponent force plates. Pitching motion was divided into two phases: phase 1 was defined as the period from when the knee of the stride leg reached maximal height (MKH: 0%time) until the point when the stride foot made contact with the ground (SFC: 100%time), while phase 2 was defined as the period from the SFC until the point when the ball was released (REL: 200%time). Ball velocity was measured using a radar gun.  The results were as follows: 1) The maximum and average ball velocities were significantly higher when pitching was performed from the mound than from the flat ground (p<0.05). 2) Hip/knee flexion angles and hip abduction/extension angular velocities on the pivot leg were significantly greater for mound pitching than for flat ground pitching, and the hip/knee extension angle and hip adduction/internal rotation/flexion angular velocities on the stride leg were significantly greater for the former (p<0.05). 3) The GRF of the stride leg was significantly greater for mound pitching than for flat ground pitching (p<0.01). 4) Upper torso and pelvis angle/angular velocities at SFC and the maximum pelvis, upper torso and trunk tilt angular velocities were significantly greater for mound pitching than for flat ground pitching (p<0.05).  The present results indicate that baseball pitchers show biomechanical differences in the kinematic and kinetic profiles of the trunk and lower limbs when pitching from the mound in comparison with the flat ground, and that high school or collegiate baseball pitchers can increase their pitched ball velocity by using the height of the mound.
著者
蔭山 雅洋 山本 雄平 田中 成典 柴田 翔平 鳴尾 丈司
出版者
日本知能情報ファジィ学会
雑誌
日本知能情報ファジィ学会 ファジィ システム シンポジウム 講演論文集 第34回ファジィシステムシンポジウム
巻号頁・発行日
pp.49-54, 2018 (Released:2019-01-09)

平成25年に文部科学省が報告した運動部活動での指導のガイドラインでは, 指導者が効果的な指導を行うには, 自身の経験に頼るだけでなく, スポーツ医・科学の研究の成果を積極的に習得し, 活用することが重要であるとされている. 近年では, センサ技術やIT技術の発展により, 計測装置の小型化が進み, バッティング直後に, スイングの結果を即時にフィードバックできる計測装置が開発されている. この計測装置では, 取得された計測データから打者のバットスイングの特徴を計測することが可能となる. しかしながら, アマチュア野球選手の指導現場では, 未だに, 科学的なデータに基づいた指導方法は, 確立されていない. その原因として, これまで我が国の野球において, 合理的な指導と非合理的な指導が混在していることに加えて, 算出された数値に対する解釈が難しいことが考えられる. そこで, 本研究では, これまで得られたデータに基づき作成した評価シートの提示が高校野球選手の打撃に関する理解および意欲に及ぼす効果を検討し, スイング計測装置を用いた打撃指導に役立てることを目的とする.
著者
蔭山 雅洋 鈴木 智晴 岩本 峰明 中島 一 前田 明
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.2, pp.737-757, 2015 (Released:2015-12-18)
参考文献数
39

The purpose of the present study was to clarify the profiles of the lower limb and trunk motion during baseball pitching in relation to their differences between the wind-up and the set positions, and to determine how the ball pitching velocity can be increased in the set position. The subjects were 12 high school baseball pitchers (age: 16.4±0.5 yr, height: 173.7±4.8 cm, weight: 64.8±8.1 kg). Pitching was assessed using a three-dimensional motion system and 2 multicomponent force plates. It was found that 1) the maximum and average pitched ball velocities were significantly lower in the set position than in the wind-up position, 2) the maximum ground-reaction force of the pivot and stride legs and the impulse of pivot during the stride phase (from the time of maximal stride knee height to the time of maximal anterior push-off force) were significantly lower in the set position than in the wind-up position, and 3) the maximum upper torso/trunk twist angular velocity and the pelvis/upper torso angular velocity at moment of the stride foot contact were significantly lower in the set position than in the wind-up position. These results indicate that 1) the ball pitching velocity in the set position is lower than in the wind-up position. In addition, the factors associated with this lower ball velocity are suggested to be 2) decreased momentum of the pivot leg and 3) decreased rotation motion of the trunk during the arm acceleration phase.   Therefore, in order to increase ball pitching velocity in the set position, increasing the moment to the rear of the pivot leg during a short period and improvement of lower limb strength/power with the extension movement of the hip and knee joint may be important factors.
著者
森 克己 山田 理恵 渡邉 修希 蔭山 雅洋
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.69, pp.276_1, 2018

<p> 高校野球は、日本固有の形態をもつスポーツ文化である。また、高校球児=丸刈りというイメージが広く国民全般に定着している。例えば、2016年3月に開催された選抜高等学校野球大会に21世紀枠で出場し選手宣誓した小豆島高校の主将が長髪であったことが大きな話題となったように、他の競技では選手の頭髪が自由であるのに対し、野球だけが選手の頭髪は丸刈りであることが当然視されている。このことは、高野連には高校球児の頭髪を丸刈りとする明文の規定がないにもかかわらず、高校の野球部員や指導者が高校球児=丸刈りという慣習法的なルールにとらわれてきた結果であると考えられる。また、その背景には、精神の鍛練がスポーツの重要な使命であることを説いた飛田穂洲の著作の中にみられる選手の頭髪についての記述のように、野球を単なるスポーツではなく精神修養を伴う「野球道」の思想等とも関連づける考え方の存在があると言える。以上のことを前提として、本研究では、高校球児の髪型=丸刈りという慣習法が成立した経緯やその慣習法の成立構造について、文献・資料及びアンケート調査結果に基づき考察する。</p>
著者
蔭山 雅洋 岩本 峰明 杉山 敬 水谷 未来 金久 博昭 前田 明
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.59, no.1, pp.189-201, 2014 (Released:2014-06-13)
参考文献数
31
被引用文献数
4

The present study measured isometric muscular strength and mean power elicited by trunk twisting and trunk rotation during pitching in 28 university baseball pitchers aged 18-22 years. Based on the correlations among these measurements, the purpose of the study was to clarify 1) the influence of ball velocity on isometric muscular strength, trunk power output during the stretch-shortening cycle (SSC) and trunk rotation during pitching and 2) the influence of augmentation which is an index of SSC elicited by trunk rotation on trunk rotation during pitching. We also determined mean power and augmentation during concentric (CT) and SSC rebound (RT) throws of medicine balls weighing 5 kg while twisting the trunk. Augmentation while throwing the medicine ball was positively correlated with ball velocity (r=0.619, p<0.01), and augmentation of the medicine ball was positively correlated with torso rotation velocity at 18-27% and at 46-75% (r=0.398-0.542, p<0.05), and trunk twist velocity at 60-66% (r=0.378-0.395, p<0.05) of the second phase (from stride foot contact to instant release of the ball) during the pitching motion. In addition, pitched ball velocity was positively correlated with the velocities of pelvic rotation at 37-78% (r=0.378-0.488, p<0.05), torso rotation at 46-87% (r=0.391-0.711, p<0.05) and trunk twist at 63-83% (r=0.375-0.499, p<0.05) during the second phase of the pitching motion. These results indicate that pitchers with a larger ball velocity can use SSC movement generated by twisting the trunk, which effectively increases trunk rotation from the first half to middle of the second phase, and they can also increase trunk rotation during the second phase.
著者
蔭山 雅洋 鈴木 智晴 杉山 敬 和田 智仁 前田 明
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.87-102, 2015 (Released:2015-06-13)
参考文献数
34
被引用文献数
4 1

The purpose of this study was to clarify the relationship between ball velocity and the mechanical power of the lower limbs during pitching motion in 30 collegiate baseball pitchers. 3-dimensional positions of 37 reflective markers attached to the subject were tracked by an optical motion capture system (Mac3D System) with 12 cameras. The ground-reaction forces (GRF) of the pivot and stride legs during pitching were determined using 2 multicomponent force plates. Pitching motion was assessed in terms of the joint torques, joint torque powers and work done by each of joint in the lower limbs using a three-dimensional motion system. The joint torques of the hip, knee, and ankle were calculated using inverse-dynamics computation of a musculoskeletal human model (nMotion musculous 1.51). Pitching motion was divided into 2 phases: phase 1 was defined as the time taken from the knee of the stride leg reaching maximal height (MKH, 0%time) to the stride foot making contact with the ground (SFC, 100%time), and phase 2 was defined as the time taken from SFC to the ball being released (REL, 200%time).  These studies revealed that the positive work resulting from hip abduction (r=0.401) and knee extension (r=0.355) of the pivot leg (Phase 1) was positively correlated with ball velocity (p<0.05). The positive work resulting from hip adduction (r=0.359) and knee extension (r=0.409) of the stride leg (Phase 2) was positively correlated with ball velocity (p<0.05). In addition, the pitched ball velocity was positively correlated with pivot hip abduction torque at 74–94%time, pivot hip internal rotation torque at 76–89%time, stride hip adduction torque at 96–114%time, stride hip adduction torque power at 108–114%time, stride knee extension torque at 101–131%time, stride knee extension angular velocities at 158–189%time, and stride knee extension torque power at 156–174%time (p<0.05).   These results indicate that a pitcher with high pitched ball velocity can generate hip abduction and knee extension power of the pivot leg, and that these are increased by hip abduction and hip internal rotation torque when moving the body forward before stride foot contact. In addition, it is suggested that high-ball-velocity pitchers can generate hip abduction and knee extension torque in order to stabilize the body just after stride foot contact, and that these are increased by the knee extension power for increasing trunk rotation and trunk twisting from the first half to the middle of the second phase.   Therefore, the present results indicate that pitchers with a higher ball velocity can generate greater mechanical power of the lower limbs for increasing the energy of trunk rotation and the arm.
著者
蔭山 雅洋 中本 浩揮
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.69, pp.209_2, 2018

<p> 本研究は、通常のボールとは大きさの異なるボール(質量は同じ)を投球することによる短期的な適応が、その後の通常ボールでの投球に及ぼす影響を明らかにすることを目的とした。被検者は、高校生の野球投手9名(年齢16.3±0.7歳、身長174.3±4.7cm、体重66.2±4.7kg、野球歴6.8±1.9yr、投手歴4.1±2.2yr)を対象とした。適応期間では、通常用いるボール(基準球)、基準球よりも-10%小さいボール、基準球よりも+10%大きいボール(+10%球)を使用し、各15球投球させた。なお、実験は、各条件の効果が互いに影響しないよう、3日に分けて実施した。適応の評価は、適応前後におけるボール速度およびコントロール誤差(捕手が構えた位置からキャッチした位置までの距離)とした。その結果、+10%球を用いた適応では、適応後のコントロール誤差は適応前よりも有意に減少した(P<0.05)。この結果より、+10%球を使用した短期的な投球適応は、投手のボールコントロールを即時的に向上させることが示唆された。そして、内省報告より、+10%球は回転数や回転軸などの球質を向上させる可能性が示唆された。</p>
著者
蔭山 雅洋 鈴木 智晴 杉山 敬 和田 智仁 前田 明
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.14061, (Released:2015-03-17)
参考文献数
35
被引用文献数
5 1

The purpose of this study was to clarify the relationship between ball velocity and the mechanical power of the lower limbs during pitching motion in 30 collegiate baseball pitchers. Three-dimensional positions of 37 reflective markers attached to the subject were tracked by an optical motion capture system (Mac3D System) with 12 cameras. The ground-reaction forces (GRF) of the pivot and stride legs during pitching were determined using two multicomponent force plates. Pitching motion was assessed in terms of the joint torques, joint torque powers and work done by each of joint in the lower limbs using a three-dimensional motion system. The joint torques of the hip, knee, and ankle were calculated using inverse-dynamics computation of a musculoskeletal human model (nMotion musculous 1.51). Pitching motion was divided into two phases: phase 1 was defined as the time taken from the knee of the stride leg reaching maximal height (MKH; 0%time) to the stride foot making contact with the ground (SFC; 100%time), and phase 2 was defined as the time taken from SFC to the ball being released (REL; 200%time).  These studies revealed that the positive work resulting from hip abduction (r=0.401) and knee extension (r=0.355) of the pivot leg (Phase 1) was positively correlated with ball velocity (p<0.05). The positive work resulting from hip adduction (r=0.359) and knee extension (r=0.409) of the stride leg (Phase 2) was positively correlated with ball velocity (p<0.05). In addition, the pitched ball velocity was positively correlated with pivot hip abduction torque at 74-94%time, pivot hip internal rotation torque at 76-89%time, stride hip adduction torque at 96-114%time, stride hip adduction torque power at 108-114%time, stride knee extension torque at 101-131%time, stride knee extension angular velocities at 158-189%time, and stride knee extension torque power at 156-174%time (p<0.05).  These results indicate that a pitcher with high pitched ball velocity can generate hip abduction and knee extension power of the pivot leg, and that these are increased by hip abduction and hip internal rotation torque when moving the body forward before stride foot contact. In addition, it is suggested that high-ball-velocity pitchers can generate hip abduction and knee extension torque in order to stabilize the body just after stride foot contact, and that these are increased by the knee extension power for increasing trunk rotation and trunk twisting from the first half to the middle of the second phase.  Therefore, the present results indicate that pitchers with a higher ball velocity can generate greater mechanical power of the lower limbs for increasing the energy of trunk rotation and the arm.