著者
平山 大作 藤井 範久 小池 関也 阿江 通良
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.59, no.2, pp.225-232, 2010 (Released:2010-05-27)
参考文献数
24
被引用文献数
2 1

The purpose of this study was to investigate the changes on mechanical work of the lower limb joints during baseball pitching in a simulated game. One male college baseball pitcher threw 15 pitches in an inning for 9 innings (135 pitches) in an indoor pitcher's mound with two force platforms. Rest time between innings was 6 minutes. Three-dimensional positions of 47 reflective markers attached to subject were tracked by an optical motion capture system (Vicon Motion System 612, Vicon Motion Systems) with eight cameras (250Hz). For subject 75 fastball pitches (1st, 3rd, 5th, 7th, and 9th innings) were chosen for analysis.As the main results, the hip joint extension absolute and negative work of the stride leg decreased with increasing the number of pitches. The ankle joint extension absolute and negative work of the stride leg increased with increasing the number of pitches. These results suggest that the hip joint extension torque of the stride leg was needed to maintain for higher performance in baseball pitching.
著者
平山 大作 藤井 範久 阿江 通良 小池 関也
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.19, pp.91-102, 2008 (Released:2017-02-15)
参考文献数
19
被引用文献数
6 1

本研究は, 大学野球投手を対象とし, 投球数の増加にともなうキネティクスの変化について検討することを目的とした. 実験試技は, 2台のフォースプラットフォームを埋設した簡易マウンドからストレートを投球するものであった. 被験者には, 10秒間隔で15球投げることを1イニングとし, イニング間に6分の休息をはさみながら9イニング, 計135球の投球を行わせた. 投球数とそれぞれのパラメータから単回帰分析を行い, 回帰係数の有意性について検定を行った (p<0.05). その結果, 投球数の増加にともない, ①踏込脚の股関節伸展の正仕事, 負仕事, 絶対仕事が減少する傾向がみられた. ②投球腕の肩関節内旋の正仕事が減少する傾向がみられた. ③投球腕への関節力による力学的エネルギーの流れの減少がみられた. ④投球腕の肩関節水平内転の正仕事および絶対仕事が増加する傾向がみられた. 以上のことから, 踏込脚の股関節伸展の仕事の減少は, 下肢のトレーニングの重要性を示唆するものであり, 投球腕の肩関節水平内転の仕事の増加は, “上肢動作に頼った投球動作” を示すものであると考えられる.
著者
阿江 数通 小池 関也 藤井 範久 阿江 通良 川村 卓 金堀 哲也
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.62, no.2, pp.559-574, 2017 (Released:2017-12-19)
参考文献数
46
被引用文献数
1

The purpose of this study was to compare the kinematic characteristics of the upper body between baseball tee batting and pitched ball batting in order to gain basic knowledge for improvement of batting skill. Ten male collegiate baseball players (age: 20.7±1.1 yr; height: 1.75±0.05 m; body mass: 76.3±7.1 kg; athletic career: 12.7±2.7 yr) participated. They performed 2 kinds of batting: tee batting (TB) and machine-pitch batting (MB) using a pitching machine (approximate ball speed 33.3 m/s), which were set at middle ball height for the strike zone. Three-dimensional coordinate data were acquired with a motion capture system. Kinematic variables such as maximum bat-head speed, swing time, bat angle, joint angles of the upper limbs, and segment angle of the upper trunk were calculated. Differences between TB and MB were analyzed statistically using paired t-test (p<0.05). The maximum bat-head speed was significantly greater in TB than in MB, but swing times divided into 2 phases showed no significant differences between MB and TB. In the first half of the swing, the bat inclination angle was significantly larger in MB than in TB. The joint angles of the barrel-side shoulder abduction, knob-side shoulder adduction and internal rotation were significantly larger in MB than in TB, and those of the barrel-side shoulder internal rotation and individual elbow pronations were significantly larger in TB than in MB. The clockwise rotational angle of the upper trunk was significantly larger in TB than in MB. In the last half of the swing, the joint angles of the barrel-side shoulder abduction, knob-side shoulder flexion and adduction were significantly larger in MB than in TB, and that of the knob-side elbow pronation was significantly larger in TB than in MB. The changes in upper body movement in MB affected the radius of rotation of the bat about the vertical axis to control the bat easily. The movements in the last half of the swing largely resulted from those in the first half of the swing, and did not contribute to timing adjustment. These results indicate that the initial configuration of the bat and upper limbs, and movements at the beginning of the bat swing contribute to the timing adjustment of the bat for a pitched ball. The results of the present study suggest that it could be useful to pay attention to the movement of the bat and upper body in the first half of the swing as TB practice in order to improve timing adjustment.
著者
藤井 範久 森脇 俊道
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.11, pp.167-178, 1992-05-20 (Released:2016-12-05)
被引用文献数
2

In order to improve human performance in competitive sports, human motions have been analyzed from various viewpoints. One of the well-known methods is to compare the patterns of joint torques with those of top athletes during the motions. However, such comparisons are not necessarily sufficient to evaluate human motion, since individual differences in muscular forces and anatomical characteristics are not taken into consideration. The aim of this study is to investigate the relationship between the optimal vertical jump (squat jump) motion and the mechanical characteristics of muscular forces. The vertical jump motions of four male subjects were analyzed; their anatomical characteristics are similar, but the muscular force characteristics are different. Each subject performed a squat jump, in response tothe command "jump ashigh as possible," from an initial squat position with 90°hip and knee angles. The reaction force from the platform, the motions of the limb and the body, and the electromyographic (EMG) data were recorded. In order to estimate the optimal control for vertical jump motion under various conditions, a simulation system is applied which is based on the musculoskeletal model with the mean characteristics of muscular forces and the anatomical parameters of the four subjects chosen. In order to investigate the relationship between the optimal vertical jump motion and the mechanical characteristics of muscular force, a series of simulations was carried out by varying the parameters of the musculoskeletal model, such as the force-velocity relationship and the maximum contraction force. The following conclusions are derived from the results of the experiments and the simulations. (1) Change in the force-velocity relationship of human muscles results in a change in the optimal vertical motion and the sequence of the firing pattern of muscles, so that the contraction velocity of muscles does not become extremely large. (2) Changes in maximum contraction forces of some muscles result in changes in the optimal vertical motion and the sequence of the firing pattern of muscles, so that each muscle contracts under the optimal condition for the vertical jump. (3) The firing pattern of muscles is governed by the relationship between the anatomical characteristics and the muscular forces, and the timing of firing is determined by the relationship between the firing patterns and the maximum muscular forces. (4) The maximum contraction forces and the force-velocity relationship have to be improved in order to improve vertical jump performance.
著者
阿江 数通 小池 関也 藤井 範久 阿江 通良 川村 卓 金堀 哲也
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.16080, (Released:2017-09-01)
参考文献数
48
被引用文献数
1

The purpose of this study was to compare the kinematic characteristics of the upper body between baseball tee batting and pitched ball batting in order to gain basic knowledge for improvement of batting skill. Ten male collegiate baseball players (age: 20.7±1.1 yr; height: 1.75±0.05 m; body mass: 76.3±7.1 kg; athletic career: 12.7±2.7 yr) participated. They performed two kinds of batting: tee batting (TB) and machine-pitch batting (MB) using a pitching machine (approximate ball speed 33.3 m/s), which were set at middle ball height for the strike zone. Three-dimensional coordinate data were acquired with a motion capture system. Kinematic variables such as maximum bat-head speed, swing time, bat angle, joint angles of the upper limbs, and segment angle of the upper trunk were calculated. Differences between TB and MB were analyzed statistically using paired t-test (p<0.05.) The maximum bat-head speed was significantly greater in TB than in MB, but swing times divided into two phases showed no significant differences between MB and TB. In the first half of the swing, the bat inclination angle was significantly larger in MB than in TB. The joint angles of the barrel-side shoulder abduction, knob-side shoulder adduction and internal rotation were significantly larger in MB than in TB, and those of the barrel-side shoulder internal rotation and individual elbow pronations were significantly larger in TB than in MB. The clockwise rotational angle of the upper trunk was significantly larger in TB than in MB. In the last half of the swing, the joint angles of the barrel-side shoulder abduction, knob-side shoulder flexion and adduction were significantly larger in MB than in TB, and that of the knob-side elbow pronation was significantly larger in TB than in MB. The changes in upper body movement in MB affected the radius of rotation of the bat about the vertical axis to control the bat easily. The movements in the last half of the swing largely resulted from those in the first half of the swing, and did not contribute to timing adjustment. These results indicate that the initial configuration of the bat and upper limbs, and movements at the beginning of the bat swing contribute to the timing adjustment of the bat for a pitched ball. The results of the present study suggest that it could be useful to pay attention to the movement of the bat and upper body in the first half of the swing as TB practice in order to improve timing adjustment.
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 4

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
木下 まどか 藤井 範久
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.143-154, 2014 (Released:2017-02-15)
参考文献数
12
被引用文献数
1

本研究の目的は, テコンドーの前回し蹴りを三次元動作分析することで, テコンドー特有の 「速い」 かつ 「早い」 蹴り動作について知見を得ることであった. そこで, 蹴り脚のキックスピードに対する下胴および蹴り脚各関節の運動におけるキネマティクス的貢献を算出した. その結果, インパクト時の膝関節伸展動作による貢献はキックスピードの約60%を占めていた. 上位群は下胴左回旋, 股関節屈曲角速度を適切なタイミングで大きくすることにより, 膝関節伸展に作用する膝関節力を生成していた. したがって, 膝関節伸展動作による貢献を増加させ, 「速い」 かつ 「早い」 蹴り動作を行うために, 下胴および股関節の動きが重要であると推察された.
著者
村田 宗紀 藤井 範久
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.2, pp.413-430, 2014 (Released:2014-12-20)
参考文献数
21
被引用文献数
9 1

The purpose of this study was to investigate the relationship between motion and ball spin in tennis serves. Ten male university tennis players participated. The three-dimensional coordinates of the players performing flat, kick and slice serves were collected using a motion capture system with 8 cameras (250 Hz). Similarly, the three-dimensional coordinates of reflective markers on the ball were also collected (500 Hz). The primary variables computed were: racquet face velocity and direction at impact, velocity and angular velocity of the ball after impact, hitting point, angles of the upper limb joints, and segment angles of the upper trunk. The differences in racquet face velocity among flat, kick, and slice serves were divided into the following terms: 1) ΔVposture: A difference in velocity resulting from a change in upper trunk posture, 2) ΔVswing: A difference in velocity resulting from a change in arm swing (kinematics of the upper limb), 3) ΔVutrk: A difference in velocity resulting from a change in upper trunk translational and rotational motion. Repeated measures ANOVA (p<0.05) with Bonferroni multiple comparison was used to evaluate the effects of changes in form (with differences in ball spin) on each parameter. The findings are summarized as follows.1)  The impact point and swing direction were mainly controlled not by a change in arm swing motion, but by a change in upper body posture.2)  To generate ball spin, it is necessary to avoid a head-on collision between the ball and the racquet (a normal vector of the racquet face is parallel to the racquet face velocity vector). Therefore, players decreased the amount of upper trunk leftward rotation in kick and slice serves at the point of impact so as to swing the racquet more laterally.3)  It is necessary to swing the racquet more vertically in order to lean the rotation axis of the ball. Therefore, players controlled the upper trunk leftward-rightward and forward-backward leaning in a kick serve at the point of impact.4)  Changes in upper body posture cause changes in the direction the racquet faces. Therefore, players mainly controlled their elbow pronation-supination angle in order to maintain a racquet face direction that satisfies a legal serve.
著者
大島 雄治 藤井 範久
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.1, pp.115-131, 2016 (Released:2016-06-17)
参考文献数
32
被引用文献数
2

The purpose of this study was to clarify the function of torques exerted by the joints of the lower trunk during maximal velocity sprinting. Eight male track and field athletes volunteered, and sprinted 60 m from a standing start position. The ground reaction force of the support leg was determined using a force platform (1000 Hz), which was placed at the 50-m mark from the start position. Simultaneously, 3D coordinates were recorded with a motion analysis system (250 Hz) using 20 cameras (MX-T20). The joint torques were calculated using inverse dynamics. The contribution of joint torques to the right and left hip joint forces, and the torso joint force, was calculated by a method that simultaneously solves equations of motion for each segment and equations of constraint conditions for adjacent segments connected by a joint. The main results were as follows: (1) During the terminal support phase (80-100% normalized time), the angular velocity of anterior rotation of the pelvis decreased and participants in whom this angular velocity decrease was diminished ran faster (p<0.10). (2) During terminal support, the hip joint adduction torque of the support leg and the anterior rotation torque of the torso joint rotated the pelvis forward. The moment of the right and left hip joint forces rotated the pelvis backward. (3) During terminal support, the hip joint force of the support leg was generated by its hip joint flexion and adduction torque, the hip joint extension torque of the recovery leg, and the anterior rotation torque of the torso joint. In contrast, the hip joint force of the recovery leg was generated by the hip joint flexion and adduction torque of the support leg, and the anterior rotation torque of the torso joint. (4) During terminal support, the hip joint flexion torque exerted by the support leg rotated the pelvis backward. The hip joint adduction torque of the support leg and the anterior rotation torque of the torso joint rotated the pelvis forward. Previous studies showed that the hip flexion torque drives the leg forward from the hip joint extension position. This present study has clarified that the hip joint adduction torque of the support leg and the anterior rotation torque of the torso joint nullify backward rotation of the pelvis due to the hip joint flexion torque exerted by the support leg.
著者
大島 雄治 藤井 範久
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.16011, (Released:2017-01-24)
参考文献数
39

The purpose of this study was (1) to quantify the contribution of the adductors and iliopsoas to the hip joint torque, and (2) to clarify the function of the adductors and iliopsoas for terminal support until early recovery in maximal velocity sprinting. Eight male track and field athletes volunteered for the present study, and sprinted 60 m from a standing start position. Ground reaction force to the right leg was measured using a force platform (1000 Hz) placed at the 50-m mark from the start position. Simultaneously, 3-dimensional coordinates of body landmarks were recorded by a motion capture system (250 Hz) with 20 cameras. The right hip joint torque was calculated using inverse dynamics. To estimate the muscle forces of the right lower limb, we created a musculoskeletal model. The contribution of the muscle forces to the right hip joint force was calculated based on both equations of motion for each segment and equations of constraint conditions for adjacent segments connected by a joint. The main results for terminal support until early recovery were: (1) The adductor muscles generated less torque during hip joint flexion. (2) These muscles were involved in forward acceleration of the leg on the same side. (3) The iliopsoas was involved in the forward swing of the thigh on the same side.  Based on these results, it can be concluded that the hip adductors do not function as hip flexors, but as forward accelerators of the leg on the same side, based on the hip joint adductor torque. In contrast, the iliopsoas does not function as a forward accelerators of the leg on the same side, but delivers forward swing to the thigh on the same side for hip joint flexion torque.
著者
伊藤 章 小林 寛道 阿江 通良 飯干 明 藤井 範久 榎本 靖士 深代 千之 杉田 正明
出版者
大阪体育大学
雑誌
基盤研究(A)
巻号頁・発行日
2006

第11回世界陸上競技選手権大会(大阪,2007)に出場した各種種目の世界一流選手と日本選手の動作分析とタイム分析をおこなった.これらの分析結果とこれまで蓄積してきたデータとを比較し,今回出場した世界一流選手たちの技術の特徴を明らかにするとともに,日本選手の技術の長所や改善すべき点を洗い出すことが出来た.多くのデータを収集できた種目に関しては,記録との相関関係をもとに普遍的ともいえる合理的技術を示すことが出来た.
著者
藤井 宏明 藤井 範久
出版者
日本バイオメカニクス学会
雑誌
バイオメカニクス研究 (ISSN:13431706)
巻号頁・発行日
vol.25, pp.14-27, 2021 (Released:2021-10-09)
参考文献数
19

The purpose of this study was to investigate the body movements to generate handle velocity in the tangential and the radial direction of hammer head during the hammer throw turn. The positive leading distance of handle has the effect of accelerating the hammer head in hammer throw. In addition, the increase and decrease of the leading distance of handle are consistent with the increase and decrease of handle velocity in the radial direction of hammer head. It will be important to clarify the movement of the body for the acquisition of the leading distance of handle by examining the acquisition of the handle velocity in the radial direction by the body movement. Throwing motions of 44 male throwers (throwing record: 80. 50–44. 17 m) participated in the study as subjects. Throwing motions were videotaped on high-speed VTR cameras, and three-dimensional coordinates were calculated using a DLT method. The handle velocity was calculated as the vector products between the anatomical angular velocity vectors of joint and the respective relative displacement vectors from the joint center to handle, by applying a mathematical model. The handle velocity obtained by body movements were projected onto the rotating plane coordinate system. The basic findings were summarized as follows: (1) The handle velocity in the radial direction can be obtained by trunk long-axis rotation, the trunk left lean, the extension of the shoulder joint, the trunk back lean, and translational movement of the body. (2) The handle velocity in the tangential direction can be obtained by the trunk long-axis rotation, trunk twist, horizontal abduction of left shoulder joint and the flexion of shoulder joint.
著者
法元 康二 阿江 通良 横澤 俊治 藤井 範久
出版者
日本コーチング学会
雑誌
コーチング学研究 (ISSN:21851646)
巻号頁・発行日
vol.24, no.2, pp.139-152, 2011

<p>&nbsp;&nbsp;&nbsp;&nbsp;The purpose of this study was to investigate technical factors relating to the maintenance of walking speed in race walking in official 20km races. Thirty-five elite race walkers were analyzed as subjects by using VTR camera (60 Hz) at 4-8km and 14-18km point during 20km official race. The results were as follows. <BR>&nbsp;&nbsp;&nbsp;&nbsp;Decreases in the recovery hip and knee joint torques resulted in decreases in the backward joint forces at the hip and knee, which decreased the joint force power at the recovery hip and knee and the mechanical energy flow from the recovery leg to the torso during the second half of the recovery phase. Therefore, decreases in the joint force at the recovery hip and knee decreased the mechanical energy flow, which might lead to decrease in the walking speed.</p>
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
村田 宗紀 藤井 範久 鈴木 雄太
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.177-195, 2015 (Released:2015-06-13)
参考文献数
23
被引用文献数
4

Mechanical energy is known to be transferred between a body segment and a joint. However, the transformation of this energy has not been classified. By focusing on the racquet-holding arm during a tennis serve, the present study examined the transformation between translational and rotational energies due to the joint force, and investigated the kinetic chain from the viewpoint of energetics. Twenty-two tennis players were asked to perform flat services to the deuce side (i.e., the receiver's right side), and the three-dimensional coordinates of reflective markers attached to each player and racquet were collected with a motion capture system. The mechanical power acting on each segment and the mechanical energy generated/absorbed by each joint were divided into the following components: (1) STP=the time rate of change in the rotational energy of a segment due to the joint torque, (2) JTP=the generation/absorption of rotational energy due to the joint torque, (3) JFPt=the time rate of change in the translational energy of a segment due to the joint force, and (4) JFPr=the time rate of change in the rotational energy of a segment due to the moment of the joint force. The findings are summarized below. 1.  The proposed method can divide the power acting on the segment due to joint force into the translational component (JFPt) and the rotational component (JFPr). 2.  The racquet-holding arm mainly acquires mechanical energy as translational energy with decreasing rotational energy of the upper trunk (around right-leftward rotation). 3.  The main role of the shoulder joint is not to generate rotational energy but to change the energy form (from translational energy to rotational energy). 4.  The main role of the phase before most of the shoulder external rotation is to store the translational energy in the racquet-holding arm. 5.  The main role of the phase after most of the shoulder external rotation is to transfer the translational and rotational energies to the racquet. 6.  The proposed method can quantify not only the generation/absorption and transmission of mechanical energy but also the transformation of the energy form. Therefore, this method may produce new findings that have not yet been clarified.
著者
平山 大作 藤井 範久 阿江 通良 小池 関也
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.19, pp.91-102, 2008
被引用文献数
1

<p>本研究は, 大学野球投手を対象とし, 投球数の増加にともなうキネティクスの変化について検討することを目的とした. 実験試技は, 2台のフォースプラットフォームを埋設した簡易マウンドからストレートを投球するものであった. 被験者には, 10秒間隔で15球投げることを1イニングとし, イニング間に6分の休息をはさみながら9イニング, 計135球の投球を行わせた. 投球数とそれぞれのパラメータから単回帰分析を行い, 回帰係数の有意性について検定を行った (p<0.05). その結果, 投球数の増加にともない, ①踏込脚の股関節伸展の正仕事, 負仕事, 絶対仕事が減少する傾向がみられた. ②投球腕の肩関節内旋の正仕事が減少する傾向がみられた. ③投球腕への関節力による力学的エネルギーの流れの減少がみられた. ④投球腕の肩関節水平内転の正仕事および絶対仕事が増加する傾向がみられた. 以上のことから, 踏込脚の股関節伸展の仕事の減少は, 下肢のトレーニングの重要性を示唆するものであり, 投球腕の肩関節水平内転の仕事の増加は, "上肢動作に頼った投球動作" を示すものであると考えられる.</p>
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 2

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.