著者

宮西 智久 森本 吉謙

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.52, no.4, pp.361-381, 2007 (Released:2007-08-08)

参考文献数

46

被引用文献数

3 3

---

A three-dimensional (3D) videography study was performed to clarify the mechanical effects of a change of pitching motion from an overhand throw (OH style) to a three-quarter throw (TQ style). Two collegiate pitchers (subjects A and B) who normally used the OH style participated. They were requested to change their original OH style into the TQ style. To do this, they were subjected to a one-year skill training program based on biomechanical principles and on knowledge such as the stretch-shortening cycle theory, muscle force-velocity relationship, and the motions of skilled pitchers (e.g., shoulder positioning at 90 degrees of abduction-adduction during the acceleration phase). Four pitches for subject A (two in pre-training, one during training and one in post-training), and three for subject B (one each in pre-training, training and post-training) were videotaped with the 3D DLT procedure using two high-speed cameras, and then analyzed. We then examined the mechanical differences between pre- and post-training. The speed of the ball at release increased progressively with every successive pitch for both subjects (Subject A : 1st : 130.3km/h ; 2nd : 133.2km/h ; 3rd : 135.7km/h ; 4th : 142.2km/h. Subject B : 1st : 131.0km/h ; 2nd : 135.0km/h ; 3rd : 139.3km/h). The pitching styles of both subjects changed from their original OH style to the TQ style, both qualitatively and quantitatively. The time-dependent patterns and peak values of the angular velocities of shoulder internal-external rotation and elbow flexion-extension of the throwing arm did not change very much. However, the peak value of the angular velocity of shoulder internal rotation occurred immediately after ball release for the OH style, while for the TQ style it occurred at ball release. As a result, the angular velocity of elbow extension at ball release was larger in the OH style than in the TQ style. On the other hand, the angular velocity of shoulder internal rotation at ball release was larger in the TQ style than in the OH style. These findings suggest that the increase in the speed of the ball is dominated by elbow extension in the OH style, and by shoulder internal rotation in the TQ style.

著者

宮西 智久 藤井 範久 阿江 通良 功力 靖雄 岡田 守彦

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.40, no.2, pp.89-103, 1995

被引用文献数

3 6

---

The purpose of this study was to investigate the differences of the motions between the speed throw and the distance throw, using a three-dimensional(3D) motion analysis. Twenty-four male university baseball players were the subjects of this study. They were asked to throw a ball (mass 0.144kg) horizontally as fast as possible (speed throw: ST), and as far as possible (distance throw: DT). These motions were filmed by two high-speed video cameras. 3D landmark coordinates of the subiects and the ball were calculated by the DLT method. The following kinematic parameters were computed: angle of release, the component velocities of the ball, the 3D angles for the backward/forward lean, right/left lean of the upper torso, and the twist of the torso and those for the abduction/adduction, horizontal flexion/extension, internal/external rotation at the shoulder joint, and the flexion/extension at the elbow joint of the throwing arm. The sequential data were normalized with the time from the stride foot contact to the ball release, and then averaged. Angle of release was significantly larger in the DT than in the ST. Significant difference was not found between the resultant velocity of the ST and the DT. Vertical velocity of the ball was significantly larger in the DT than in the ST during the latter half of the acceleration phase. On the other hand, horizontal velocity of the ball was significantly larger in the ST than in the DT. The backward lean and the left lean angles of the upper torso were also significantly larger in the DT than in the ST throughout the all sequences analyzed. Ranges of these angular displacements between the stride foot contact and the release, however, had no significant difference between the ST and the DT. The shoulder adduction angle was also significantly larger in the DT than in the ST during the latter half of the acceleration phase. These results indicate that the differences in the release parameters between the ST and the DT were caused not only by the throwing arm motions but also by the motions of the upper torso. It has been suggested that the motions to upward and left ward of the upper torso helps to achieve longer throwing distance in the DT, and that forward lean of the upper torso possibly contributes to achieve larger horizontal ball velocity at the release in the ST.

著者

宮西 智久 森本 吉謙

出版者

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.52, no.4, pp.361-381, 2007

被引用文献数

1 3

---

A three-dimensional (3D) videography study was performed to clarify the mechanical effects of a change of pitching motion from an overhand throw (OH style) to a three-quarter throw (TQ style). Two collegiate pitchers (subjects A and B) who normally used the OH style participated. They were requested to change their original OH style into the TQ style. To do this, they were subjected to a one-year skill training program based on biomechanical principles and on knowledge such as the stretch-shortening cycle theory, muscle force-velocity relationship, and the motions of skilled pitchers (e.g., shoulder positioning at 90 degrees of abduction-adduction during the acceleration phase). Four pitches for subject A (two in pre-training, one during training and one in post-training), and three for subject B (one each in pre-training, training and post-training) were videotaped with the 3D DLT procedure using two high-speed cameras, and then analyzed. We then examined the mechanical differences between pre- and post-training. The speed of the ball at release increased progressively with every successive pitch for both subjects (Subject A : 1<SUP>st</SUP> : 130.3km/h ; 2<SUP>nd</SUP> : 133.2km/h ; 3<SUP>rd</SUP> : 135.7km/h ; 4<SUP>th</SUP> : 142.2km/h. Subject B : 1<SUP>st</SUP> : 131.0km/h ; 2<SUP>nd</SUP> : 135.0km/h ; 3<SUP>rd</SUP> : 139.3km/h). The pitching styles of both subjects changed from their original OH style to the TQ style, both qualitatively and quantitatively. The time-dependent patterns and peak values of the angular velocities of shoulder internal-external rotation and elbow flexion-extension of the throwing arm did not change very much. However, the peak value of the angular velocity of shoulder internal rotation occurred immediately after ball release for the OH style, while for the TQ style it occurred at ball release. As a result, the angular velocity of elbow extension at ball release was larger in the OH style than in the TQ style. On the other hand, the angular velocity of shoulder internal rotation at ball release was larger in the TQ style than in the OH style. These findings suggest that the increase in the speed of the ball is dominated by elbow extension in the OH style, and by shoulder internal rotation in the TQ style.

著者

宮西 智久 柴山 一仁 門野 洋介

出版者

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

no.63, 2012-08-22

著者

宮西 智久 藤井 範久 阿江 通良 功力 靖雄 岡田 守彦

出版者

Japan Society of Physical Education, Health and Sport Sciences

雑誌

体育学研究 (ISSN:04846710)

巻号頁・発行日

vol.40, no.2, pp.89-103, 1995-07-10 (Released:2017-09-27)

被引用文献数

4 6

---

The purpose of this study was to investigate the differences of the motions between the speed throw and the distance throw, using a three-dimensional(3D) motion analysis. Twenty-four male university baseball players were the subjects of this study. They were asked to throw a ball (mass 0.144kg) horizontally as fast as possible (speed throw: ST), and as far as possible (distance throw: DT). These motions were filmed by two high-speed video cameras. 3D landmark coordinates of the subiects and the ball were calculated by the DLT method. The following kinematic parameters were computed: angle of release, the component velocities of the ball, the 3D angles for the backward/forward lean, right/left lean of the upper torso, and the twist of the torso and those for the abduction/adduction, horizontal flexion/extension, internal/external rotation at the shoulder joint, and the flexion/extension at the elbow joint of the throwing arm. The sequential data were normalized with the time from the stride foot contact to the ball release, and then averaged. Angle of release was significantly larger in the DT than in the ST. Significant difference was not found between the resultant velocity of the ST and the DT. Vertical velocity of the ball was significantly larger in the DT than in the ST during the latter half of the acceleration phase. On the other hand, horizontal velocity of the ball was significantly larger in the ST than in the DT. The backward lean and the left lean angles of the upper torso were also significantly larger in the DT than in the ST throughout the all sequences analyzed. Ranges of these angular displacements between the stride foot contact and the release, however, had no significant difference between the ST and the DT. The shoulder adduction angle was also significantly larger in the DT than in the ST during the latter half of the acceleration phase. These results indicate that the differences in the release parameters between the ST and the DT were caused not only by the throwing arm motions but also by the motions of the upper torso. It has been suggested that the motions to upward and left ward of the upper torso helps to achieve longer throwing distance in the DT, and that forward lean of the upper torso possibly contributes to achieve larger horizontal ball velocity at the release in the ST.

著者

宮西 智久 藤井 範久 阿江 通良 功力 靖雄 岡田 守彦

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.41, no.1, pp.23-37, 1996-05-10 (Released:2017-09-27)

被引用文献数

7

---

We investigated the contribution of the motions in the upper torso and the throwing arm joints to the ball velocity during the baseball throw. The ball velocities caused by the anatomical rotations at the upper torso, shoulder, elbow, wrist and metacarpophalangeal joints were calculated as the vector products between the anatomical angular velocity vectors of joints and the respective relative displacement vectors from the joint centers to the center of ball, by using a mathematical model reported by Sprigings et al. (1994). Horizontal throws of twenty-four male university baseball players were filmed using a three-dimensional DLT method. In order to verify the ball velocities obtained from the anatomical joint rotations from the instant of the stride foot contact to the ball release, the velocity of ball measured directly from video recording was compared with that calculated by the mathematical model. A good agreement was acquired between the velocity of ball measured and that calculated. The velocities obtained from the left-rotation, flexion at the upper torso joint and the horizontal flexion at the shoulder joint contributed to the ball velocity in the early phase where the increase of ball velocity was slow. The velocities obtained from the internal-rotation at the shoulder joint, extension at the elbow joint, palmar-flexion at the wrist joint, and left-rotation/flexion at the upper torso joint contributed in the late phase where the increase of ball velocity was rapid. At the ball release, the contribution of each joint, which is the ratio of the positive ball velocity obtained from the anatomical joint rotations to the summation of individual positive ball velocities was as follows; 34.1% by the internal-rotation at the shoulder, 17.7% by the palmar-flexion at the wrist, 15.2% by the extension at the elbow, and 9.6% by the left-rotation at the upper torso joint.

著者

宮西 智久 宮永 豊 福林 徹 馬見塚 尚孝 藤井 範久 阿江 通良 功力 靖雄 岡田 守彦

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.48, no.5, pp.583-595, 1999-10-01 (Released:2010-09-30)

参考文献数

36

被引用文献数

2 3

---

This study was designed to clarify the causes of throwing injuries of the elbow and shoulder joints in baseball. Five varsity-skilled baseball players without pain in the elbow and shoulder joints were subjects for this study. They were fixed to a chair and asked to throw a baseball using three different throwing arm movements (T0, T45, and T90) . These movements were filmed using three-dimensional DLT videography. Linked rigid-body segment inverse dynamics were then employed to determine resultant joint force and torque at the elbow and shoulder joints. Peak varus torque at the elbow joint for T90 was less than for the other movements during the acceleration phase. In the follow-through phase, however, a large anterior shear force (70 N) at the elbow, for elbow extension, was present for T90. These results indicate that T90 was a high risk movement which leads to extension injuries rather than medial tension injuries. After the ball release, a large superior shear force (118 N) at the shoulder joint was present in all movements. This superior force may result from the subacromial impingement syndrome, except for critical zones of impingement caused by the different throwing arm movements. These findings suggest that the mechanisms of throwing arm injuries are closely related to differences in throwing arm movements.

著者

宮西 智久 桜井 伸二

出版者

社団法人日本体育学会

雑誌

日本体育学会大会号

巻号頁・発行日

no.50, 1999-09-15

著者

宮西 智久 柴山 一仁 門野 洋介

出版者

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

no.64, 2013-08-28