著者

久保 啓太郎 金久 博昭

出版者

東京大学

雑誌

萌芽研究

巻号頁・発行日

2007

---

(研究1)長距離選手および短距離選手における筋腱の力学的特性と跳躍能の比較 陸上長距離選手15名、陸上短距離選手15名を対象にして、下肢筋群(膝伸筋群、足底屈筋群)の筋厚、等尺性最大筋力、筋活動水準およびtwitch特性、腱の力学的特性、跳躍能(SJ,CMJ,DJ,連続ジャンプなど)を測定した。筋厚、最大筋力、活動水準は、長距離選手群が短距離選手群よりも有意に低い値を示した。電気刺激中の最大張力までの到達時間(筋の収縮速度を示す)は、速筋線維を多く有すると思われる短距離選手は短く、逆に遅筋線維を多く有すると思われる長距離選手は長かった。腱の力学的特性については、膝伸筋群において短距離選手が伸びやす<、足底屈筋群において長距離選手が伸びにくい傾向を示した。跳躍能についてはいずれにおいても長距離選手が短距離選手よりも有意に低い値を示した。現在は、上記の結果をもとにして投稿論文を作成中である。(研究2)陸上長距離選手における筋腱の力学的特性と跳躍能のシーズン毎の変化 陸上競技長距離選手15名(箱根駅伝常連校のメンバー)を対象にして、休養期(2月)、トラック(スピード)練習期(5月)、鍛錬期(9月)の3回にわたり、下肢筋群(膝伸筋群、足底屈筋群)の筋厚、等尺性最大筋力、筋活動水準およびtwitch特性、腱の力学的特性、跳躍能(SJ,CMJ,DJ,連続ジャンプなど)、規定速度における走行中の酸素摂取量を測定した。最大筋力、活動水準、跳躍能には、有意な変化は観察されなかったが、9月における走行中の酸素摂取量が低<なる傾向を示した。その他の項目については、現在分析をすすめている。

著者

久保 啓太郎 金久 博昭 福永 哲夫

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.50, no.6, 2001-12-01

著者

池袋 敏博 久保 啓太郎 岡田 純一 矢田 秀昭 角田 直也

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.60, no.4, pp.401-411, 2011 (Released:2011-08-30)

参考文献数

37

被引用文献数

7 7

---

This study aimed to investigate the differences in the development of muscle thickness (MT) in the lower limbs with specific sports-event training. Furthermore, the relationship between MT of the lower limbs for weightlifters and sprinters and their competition performances (total weight lifted and 100m sprint times) was examined. Subjects were 64 males divided into 3 groups: weightlifters (n=20), sprinters (n=20), and untrained subjects as controls (n=24). The MT{relative to (body weight)1/3}of knee extensors (KE), knee flexors (KF), plantar flexors (PF) and dorsi flexors (DF) was measured at 21 sites (proximal, middle and distal) along the length of the upper and lower leg by B-mode ultrasound. The MT of KE for weightlifters was significantly greater than that for sprinters and controls, while the MT of KF and PF for sprinters was significantly greater than that for weightlifters and controls. The MT of rectus femoris (RF), vastus intermedius (VI), vastus lateralis (VL) and vastus medialis (VM) for weightlifters was significantly greater than that for sprinters and controls, while the MT of RF and VM for sprinters was greater than that of controls. On the other hand, the MT of KE for weightlifters and sprinters (especially VM) correlated significantly with competition performances. These results indicated that squatting affected the MT of KE except for RF while sprinting affected the MT of KF and PF. It was also concluded that the MT of KE for weightlifters and sprinters (particularly VM) was related to their competition performances.

著者

久保 啓太郎 川上 泰雄 金久 博昭 福永 哲夫

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.597-605, 1999-10-01 (Released:2010-09-30)

参考文献数

32

被引用文献数

4 5

---

The purpose of this study was to investigate the viscoelastic properties of tendon structures in humans. Elongation of the tendon and aponeurosis of medial gastrocnemius muscle (MG) was directly measured by ultrasonography, while subjects (N=12) performed ramp isometric plantar flexion up to the voluntary maximum, followed by a ramp relaxation. The relationship between estimated muscle force (Ff) and tendon elongation (dL) was fitted to a linear regression, the slope of which was defined as stiffness of the tendon structures. The hysteresis was calculated as the ratio of the area within the Ff-dL loop (elastic energy dissipated) to the area beneath the load portion of the curve (elastic energy input) . The resulting Ff-dL relationship was non-linear in form, as previously reported on animal and human tendons in vitro. The mean stiffness was 24.0±5.6 N/mm. However, there was a considerable inter-subject variability (15.8 to 36.8 N/mm) . The Young's modulus, i. e., the slope of the stress-strain curve, was 280 MPa, which tended to be lower than the previously reported values for human tendons. It was also found that the strain of the tendon structures was homogeneously distributed along its length. The mean hysteresis (energy dissipation) was 23.4±12.4%. However, again there was a considerable inter-subject variability (8.7 to 39.3%) . The present results indicated that the tendon structures of human MG was considerably compliant and its hysteresis was in accordance with previously reported values.

著者

吉田 博幸 久保 啓太郎 加賀谷 〓彦

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.43, 1992-10-31