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

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
湯 海鵬 阿江 通良
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.12, pp.73-84, 1994
被引用文献数
2

This study was designed to analyze the jumping forehand smash of elite players based on three-dimensional kinematic data, and to gain insight into the basic badminton smash technique. Jumping smashes of four male elite players were filmed with two high-speed cameras operating at 250Hz with exposure times of 1/1500 and 1/1250 s. Nine jumping smashes were selected for the analysis, and were digitized from the take-off of the jump to the end of the swing in the air. Thirty three-dimensional coordinates for the segment endpoints and racket were computed by a Direct Linear Transformation Method. Small reference poles were fixed to the forearms of the swing arms of the subjects to detect the movements of the radio-ulnar joint and wrist joint. The following six joint angle changes were obtained throughout the smash motion. (a) abduction/adduction angle at the shoulder joint; (b) internal rotation/external rotation angle at the shoulder joint; (c) flexion/extension angle at the elbow joint; (d) pronation/supination angle at the radio-ulnar joint; (e) radial flexion/ulnar flexion angle at the wrist joint; (f) palmar flexion/dorsiflexion angle at the wrist joint. The results showed that internal rotation of the shoulder joint, extension of the elbow joint, and pronation of the radio-ulnar joint seemed to contribute to produce great velocities of the racket head, because the three rotations occurred over the greatest range in the shortest time in the six rotations immediately before contact with the shuttle. Preliminary to the three motions were motions in the opposite direction: external rotation of the shoulder, flexion of the elbow, and supination of the forearm were detected. These motions in the opposite direction would be useful to extend the range of the motion in each joint angle. The results also appeared to be related to intrinsic muscle properties, that greater power can be exerted by the stretching-shortening cycle of the muscles. The time of the last joint rotation starting immediately before contact was in the order of decreasing inertia. Times required for the rotation until contact became shorter in order of occurrence. The faster the rotation was, the later it occurred, and the shorter was the rotation time. This kind of chain and continuous movement of different joints, and different freedom with the same joint, may accelerate the racket head efficiently. The averages of elbow angle and racket angle (the angle between the forearm and racket shaft) were 160.0°and 147.0°at contact, respectively the values may be the suitable choices between the contact height and contact speed in practical play.
著者
眞鍋 芳明 桜井 健一 岩壁 達男 尾縣 貢
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.69-80, 2008 (Released:2017-02-15)
参考文献数
27

本研究の目的は, スクワットトレーニングにおける運動速度を含むトレーニングプロトコルの違いが筋断面積, 筋力および運動パフォーマンスに与える影響を検証することである. 被検者を高重量・低回数負荷で行うStrength群, 5秒間かけて下降および挙上を行うSlow群, そして軽重量を用いて全運動範囲において最大速度で行うSpeed群の3群に分け, 6~8週間のトレーニング前後に身体組成, 筋力および運動パフォーマンステストを実施した. その結果, Slow群においては筋肥大が確認されたものの, 運動パフォーマンスは向上せず, Strength群およびSpeed群においては, 身体組成においては変化が認められなかったが, 跳躍および30m疾走パフォーマンスの向上が認められた.
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

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
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
山崎 信寿
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.10, pp.85-95, 1990-09-10 (Released:2016-12-05)

Bipedal dinosaurs are huge and curious animals that have short forelimbs, powerful hindlimbs, and a long and heavy tail. The restoration of their posture and locomotion is difficult because of the lack of resemblant living animals. In this study, we paid attention to the harmony between animal motion and body shape, and conversely estimated the posture and locomotion of the bipedal dinosaurs from the characteristics of the body proportions using a computer simulation method. The mathematical model was constructed by the three-dimensional rigid link system with the following fourteen segments: head, neck, thorax, pelvis, upper arms, forearms, thighs, shanks, bottom tail, and top tail. An axis of the central body segments rotates about the vertical axis with a constant pitch angle defined by the initial posture. Each limb moves in the sagittal plane of the thorax or pelvis segment. Body weight is supported by the lumbar joint. Both torque spring and damper element are attached in each joint to prevent large relative rotation. Nonlinear elasticity is given in the knee and elbow joints to avoid hyper-extension of the joint. Using these assumptions, we can deduce seventeen simultaneous second-order differential equations. The numerical calculation of the oscillation mode was performed by using the fourth-order Runge-Kutta method. By means of this method, we analyzed Allosaurus, which was a typical bipedal dinosaur in the Jurassic period. The length of each segment was estimated from measured data of fossil skeletons. Other physical parameters, such as weight, moment of inertia and center of mass of each segment, were calculated geometrically from the restored shape. The torque spring and damper elements of each joint were referred from living animals. The numerical calculations were performed by assuming several body proportions and postures. The following results were obtained: Stability and walking speed with erect posture are inferior to the horizontal posture. The long and heavy tail is useful to obtain harmonic motion and greater speed. But the weight of the short forelimbs has almost no effects on the locomotion. The narrow distance between the hip joints increases the walking speed and decreases the swing of the body. The walking speed calculated by the stride of fossil pit and the oscillation frequency of the hindlimbs is 5.6km/h, which is within the speed range of mammals. Consequently, we can reconstruct the walking of Allosaurus, which held its trunk and tail horizontal and moved stably at almost mammalian speed.
著者
中島 求 茂木 勇悟
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.81-90, 2008 (Released:2017-02-15)
参考文献数
13

本研究では, 水泳における筋骨格解析を可能とするため, 著者らが開発ずみで水泳の動力学解析が可能な水泳人体シミュレーションモデルSWUMと筋骨格モデルを統合した, 水泳用全身筋骨格シミュレータを開発した. そのため, まず身体形状, 関節運動, および流体力のSWUMからの出力情報を筋骨格モデルに入力するデータ変換手法を構築した. 次に, 構築したデータ変換手法を, SWUMが実装されたソフトウェアに実装することにより, 統合シミュレータ化を行った. そして開発したシミュレータを用いて, クロール, 平泳ぎ, 背泳ぎ, バタフライの4泳法の解析を行った. さらに従来研究の筋電図測定結果と比較することにより, 本シミュレータの妥当性を検証した. その結果, 本シミュレータによる解析結果は筋電図測定結果と筋力発揮タイミングについて良く一致し, 筋力発揮タイミング推定に関しての本シミュレータの妥当性が確認された.
著者
長尾 秀行 山田 洋 小河原 慶太 有賀 誠司 小金澤 鋼一
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.23, pp.161-172, 2016 (Released:2017-08-01)
参考文献数
23

本研究の目的は, 力発揮能力改善を目的としたトレーニングであるクイックリフト (以下QL) 動作時の力発揮特性とそのメカニズムを検討することである. 代表的なQLであるパワークリーンを対象に挙上重量が大きい者と小さい者各6名の動作分析の結果, 最大挙上重量が大きい者は, 下肢関節最大トルクとセグメント間のエネルギの流出入量が大きく, 特有の反動動作が見られた. さらに, 最大挙上重量が大きい者と小さい者各10名の筋電図分析と動作分析の結果, 挙上重量が大きい者と小さい者間の下肢関節伸展筋の筋活動度は同等で, 屈筋と伸筋の筋活動から推定した関節剛性と関節トルク立ち上がり速度は挙上重量が大きい者の方が反動動作の前後において大きな値を示した. このことから, QL時の大きな力発揮には下肢関節の剛性を巧みに制御し, エネルギ伝達の効率化を図る必要があることが示された.
著者
阿江 通良 湯 海鵬 横井 孝志
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.23-33, 1992-05-20 (Released:2016-12-05)
被引用文献数
131 178

Inertia properties of the body segments such as segment mass, location of the center of mass, and moment of inertia can be measured and predicted in a number of ingenious approaches. They can be classified into a) direct measurements on cadavers, b) indirect measurements on living subjects, and c) mathematical modelling. However, there is little information upon which complete inertial estimates for Japanese people, especially male and female athletes, can be based. The purposes of this study were to determine the mass, center of mass location, and moments of inertia of the body segments for Japanese male and female athletes using a mathematical modelling approach, and to develop a set of regression equations to estimate inertia properties of body segments using simple anthropometric measurements as predictors. Subjects were 215 male and 80 female athletes belonging to various college sport clubs. Each subject, wearing swimming suit and cap, was stereo-photographed in a standing position. Ten body segments including the upper and lower torso were modelled to be a system of elliptical zones 2cm thick based on Jensen and Yokoi et al. Significant prediction equations based on body height, body weight, and segment lengths were then sought, and some prediction strategies were examined. The results obtained were summarized as follows: 1) Table 2 provides a summary of mass ratios, center of mass location ratios and radius of gyration ratios for males and females. There were many significant differences in body segment parameters between the two sexes. This suggests the need to develop different prediction equations for males and females. 2) Close relationships were noted between segment masses and segment lengths and body weight as predictors for all body segments. Table 5 provides coefficients of multiple regression equations to predict segment masses. 3) No close relationship was noted between independent variables and estimates of the center of mass location. This indicates that the variance in the center of mass location in proportion to the segment length was very small, and that location of centers of mass could be estimated by the mean ratio provided in Table 2. 4) Close relationships were noted between segment moments of inertia and segment lengths (except hand and foot), and body weight as predictors. Tables 6 and 7 provide coefficients of multiple regression equations to predict segment moments of inertia from segment lengths and body weight.
著者
小幡 哲史 木下 博
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.37-47, 2014 (Released:2017-02-15)
参考文献数
9

3軸小型力覚センサーを指板に埋め込んだ実験用バイオリンを用いて, 熟練奏者と初心者を対象にビブラート音なしでの単音演奏とビブラート音演奏での指板力を計測した. また, 一部の熟練奏者ではそれに関わる左手の筋活動も同時に計測した. 熟練奏者の単音演奏では, 弦を押さえる瞬間に, 指板力の鋭い立ち上がりが見られ, 遅いテンポではその後力が減少した状態で保たれるが, 速いテンポではパルス波形のみが見られた. ピークの力は1, 2 [Hz] では4.5 [N] を超える程であったが, それより速いテンポでは力が減少した. 一方で, 手内および前腕の筋活動はテンポが速くなるにつれて増大した. 初心者は熟練者に比べ, テンポや指の違いに関わらず, 力発揮が弱かった. ビブラート音演奏では, 熟練者は弦を固定するために一定の垂直方向への力を加えた上で, 弦長を変化させるための長軸方向への力を加えていた. 本研究は, 実際の演奏における指板力の測定を実現し, 得られた指板力情報とテンポや指, ビブラート音や経験の差について, また関連する筋活動について議論した.
著者
眞鍋 芳明 桜井 健一 岩壁 達男 尾縣 貢
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.19, pp.69-80, 2008

<p>本研究の目的は, スクワットトレーニングにおける運動速度を含むトレーニングプロトコルの違いが筋断面積, 筋力および運動パフォーマンスに与える影響を検証することである. 被検者を高重量・低回数負荷で行うStrength群, 5秒間かけて下降および挙上を行うSlow群, そして軽重量を用いて全運動範囲において最大速度で行うSpeed群の3群に分け, 6~8週間のトレーニング前後に身体組成, 筋力および運動パフォーマンステストを実施した. その結果, Slow群においては筋肥大が確認されたものの, 運動パフォーマンスは向上せず, Strength群およびSpeed群においては, 身体組成においては変化が認められなかったが, 跳躍および30m疾走パフォーマンスの向上が認められた.</p>
著者
増田 正 遠藤 博史 武田 常広
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.15, pp.63-73, 2000-06-15 (Released:2016-12-05)
参考文献数
17

In recent years SQUID (Superconducting Quantum Interference Device) technology has developed rapidly in both sensitivity and number of recording channels. Biomagnetic measurements based on SQUID technology are considered to have great potential in the analysis of brain and heart functions. They are also applicable to skeletal muscles and may provide a new method for diagnosing neuromuscular functions. To clarify the capability for biomagnetic measurements, the magnetic recording technique was applied to the vastus lateralis and the vastus medialis of three healthy male adults. Magnetic fields were measured with a 64-channel SQUID system. Discharges of single motor units were simultaneously detected by surface electromyography under a weak voluntary contraction. The magnetic signals were averaged for 64 to 158 times at the zero-crossings in the surface electromyogram. Six motor units were detected in the three subjects. The isofield maps of magnetic fields showed current sources arising from the motor endplate regions and spreading in opposite directions to the tendons. A current octupole moving along muscle fibers explains these magnetic fields. Because the magnitude of the magnetic fields is directly proportional to the intensity of the currents in the muscle fibers and is independent of the conductivity of the surrounding medium under certain conditions, it is possible to calculate the intensity of the currents in the muscle fibers. To improve the accuracy of such calculations, a model of the muscle fiber action currents was developed, taking into consideration the intensity and duration of the current source. A magnetic field was calculated from an octupole current model. The measured magnetomyographic signal waveform was deconvoluted with the calculated magnetic field signal produced by a single muscle fiber. The area of the deconvoluted waveform represents the number of active muscle fibers, which was estimated at 708 to 1,791 (average 1,088±480) for the six motor units detected. These numbers were 6.5 times larger than those estimated from the intensity of the current source alone without considering its duration, and were close to the invasively obtained values. The number of muscle fibers contained in a muscle or a motor unit has until now been estimated only by an anatomical method. Noninvasive magnetic measurement should therefore contribute to the diagnosis of neuromuscular diseases that cause the decrement or shrinkage of muscle fibers.
著者
山崎 信寿 高橋 直己
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
no.17, pp.235-244, 2004-08-25
被引用文献数
5

Body care motions apply a large amount of stress on caregivers' muscles and spines, so most of them suffer from low back pain. One of the major factors of low back pain is the low back muscular load to keep the deep flexion posture. This study concerned development of a suit-type back muscle supporter named "the care suit," which reduces low back load. Elastic fiber belts (support lines) are arranged on the back and leg parts of the suit. The support lines are relaxed so as not to interfere with daily trunk motion, arm motion, walking, and sitting motion, but to exert tensile force and extension moment in the deep flexion posture. The care suit is a two-piece design to improve comfort and convenience. To optimize the layout of the support lines we developed a small reel-type device to measure body surface deformation. As the result of measurement by this device and a system for posture measurement during several motions, the back support lines are arranged in an x-shape from the side neck point to the point internally dividing the Jacoby-line at a ratio of 1 to 2. The leg support lines branch at the rear face of the thigh and are attached to the apex of the patella. The maximum tension of support lines is limited by the user's shoulder pain to 140 N for males and 85 N for females. The effect of the care suit was evaluated by electromyograms of back muscles. The action potential in the deep flexion posture was 25% decreased. In comparison with the conventional corset, the effect of the care suit for back muscle was equal, but the care suit is superior in that it does not interfere with flexion motion. The lumbar joint muscular moment during a diaper change operation was calculated from body posture through a rigid body link model. The results of this calculation showed that the stored load during the operation was decreased by 30% by the care suit. Furthermore the summation of intervertebral disk compressive force was reduced by 15% during the operation. Therefore the care suit is effective for reduction of not only continuous muscular load but also spinal load. Practical use by caregivers also resulted in good evaluations as it reduced continuous muscle load for a diaper change operation, bed making operation, etc. Conclusively, the low back load during body care motions can be reduced by the care suit developed in this research. This care suit is under patent application.
著者
高西 淳夫 谷 知之 田名瀬 崇 加藤 一郎
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.10, pp.71-81, 1990
被引用文献数
5 1

Numerous studies on the neurophysiology and anatomy of the control system of mastication have been done, but most of them are only qualitative, not quantitative and dynamic. The authors believe that the mechanism of mastication can be analyzed quantitatively using a mathematical model and that an artificial mastication system can be developed on the basis of the results. The purpose of this study was to develop a 3 DOF (degrees of freedom) artificial mandible model WJ (Waseda Jaw)-2 and to simulate mandible motion in mastication. We hypothesized that a mandible modeled as a rigid body has 4DOF because the left and right condylar paths are constrained by the kinematic axis. The WJ-2 has 3DOF since the thrust movement along the kinematic axis is so small that it can be negligible. Artificial muscle actuators (AMAs) using DC servo motors drive the WJ-2. The WJ-2 has four kinds of AMAs: the m-colliant. (to open), the m-masseter (to close), the m-pterygoideus lateralis (to move forward), and the m-temporalis post. (to move backward). They are assigned around the jaw with reference to the anatomic data and the authors' computer simulation. We decided that the incisal point tracing shown by Gysi is the target motion of the WJ-2. It consists of 4-phases. Phase 1 is the opening phase, 2 is the turning phase (opening to closing), 3 is the closing phase, and 4 is the occlusal phase. The authors considered that the incisal point tracing can be drawn by fixing the working side condyle, moving the balancing side condyle, and rotating the jaw around the kinematic axis. The authors have determined that there are 2 levels of control systems in mastication. One is the muscle control system of each masseter muscle, which is the lower-level system. The other is the mastication control system, the upper-level system, which supervises and controls the muscle control systems. The muscle control system controls the muscle by position and velocity feedback of the muscle spindle. Feedback gain is variable. The mastication control system creates movement patterns of the mandible, sends it to the muscle control system, and supervises jaw reflexes. The control sequence of the WJ-2 is also divided into 4 phases according to Gysi's theory. The change from the occlusal to the opening is under the control of a normal position pattern. The jaw opening reflex and unloading reflex are used when accidents occur in mastication. And the WJ-2 has the function that the maximum mandible opening position changes adaptively as food is deformed. The authors conducted a mastication experiment with food. As a result, the WJ-2 realized mandible movement that suits Gysi's 4-phase theory and realized mastication movement that matches deformation of food.
著者
藤本 浩志 滝田 久芳 有田 道生 小金沢 鋼一 加藤 一郎
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.9, pp.241-251, 1988
被引用文献数
4 1

Conventional A/K prostheses have been designed only for level walking, so A/K amputees have been compelled to walk on stairs with unnatural posture. To expand A/K amputees' daily mobility, the goal of this study is to develop an A/K prosthesis which allows amputees to ascend/descend stairs as well as to walk on a flat surface. The WLP-8 R developed in our study featured a mechanism that can generate a powerful moment at the joints large enough to ascend the stairs. First, this paper presents the Hydraulic/Electric Hybrid Actuator composed of a hydraulic power assembly and an electric power assembly to realize level and stairs walking. In level and downstairs walking, the amputee can walk only with the hydraulic power assembly that generates the extension moment of knee joint during a swing phase using the hydraulic power which has been previously accumulated by the passive rotation of the two joints (knee and ankle) during the last stance phase. So no additional power system is necessary as to realize level and downstairs walking. In upstairs walking, the amputee can walk using the Hydraulic/Electric Hybrid Actuator. The electric power is transmitted through the ball-screw driven by the DC motor to the piston-rod of the knee joint, which has also been pushed up by the hydraulic power as well as level walking so that the knee joint is extended by the combined powerful force of hydraulic and electric power. Second, the Automatic Dorsal-Flexion Mechanism that improves the posture during level walking is described. Third, the construction of the WLP-8 R system is described. Performance of amputees wearing the WLP-8 R and walking is described and discussed. Two A/K amputees could walk on a flat surface and stairs like normal subjects. These walking experiments confirmed the applicability of this system.
著者
阿江 通良 宮下 憲 飯干 明
出版者
バイオメカニズム学会
雑誌
バイオメカニズム
巻号頁・発行日
vol.9, pp.105-113, 1988
被引用文献数
3

The purposes of this study were to analyze energy flows between lower limb segments during a cycle of sprinting and to clarify the characteristics of two different running motions, starting dash and sprinting at a constant speed, by comparing their energy flows. Three male sprinters dashed 20m and ran 100m giving their full effort. They were filmed at the 1-step and 5-step points after the start and at the 80m mark of the 100m sprint with a motion-picture camera. Ground reaction force data were simultaneously sampled at 500Hz. Digitized x and y coordinates of the body marks were smoothed by a digital filter cutting off at 8Hz for the start dash and 10Hz for sprinting. A 14-segment link modelling was used to compute linear and angular kinematics, joint forces, and net muscle moments. Joint force and muscle moment powers (abbreviated JP and MP) were computed as defined by Robertson and Winter (1980). Analysis and comparison of energy flow in a starting dash and sprinting at a constant speed revealed that: 1) Magnitude of energy flow by JP was much greater than that of MP in sprinting, while the difference in power level of JP and MP was less 1 step after the start. 2) In the early recovery period of sprinting, energy in the lower limb flowed from the trunk toward the foot, and it flowed in the reverse direction in the late recovery period. In the support period, the muscles at the ankle and knee joints absorbed most of the energy. Energy flowed from the trunk and thigh to the shank in the first half of the support period, and from the foot to the shank and from the trunk to the shank through the thigh in the second half. 3) In the recovery period of the starting dash energy flowed in the same manner as in sprinting. However, in the support period, the energy flowed from the foot to the thigh and the trunk. Notable was energy flow from the opposite thigh (i.e., the recovery thigh) to the trunk. From the viewpoint of energy flow patterns in the lower limb, a starting dash may be characterized as the running motion that accumulates as much mechanical energy in the trunk as possible through the generation of energy by the knee joint muscles and the transfer of energy to the trunk from the leg, especially the opposite leg at the support stage. Sprinting at constant speed may be characterized as the running motion to redistribute the energy between the body segments and the trunk with the minimum loss of energy.