- 著者
- Yasuo Kawakami
- 出版者
- 一般社団法人日本体力医学会
- 雑誌
- The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)
- 巻号頁・発行日
- vol.1, no.2, pp.287-296, 2012-07-25 (Released:2012-09-11)
- 参考文献数
- 63
- 被引用文献数
- 5
The biomechanical features of skeletal muscles are reviewed, with regard to their form and function and anatomical components (fascicles and tendinous tissues). 1) Studies on fascicle architecture are reviewed, highlighting its importance in the force and velocity potentials of the muscle along with its plasticity and muscle-size dependence. 2) The elastic properties of the muscle-tendon unit are described, pointing out the contribution of tendinous tissues as a spring. Functional consequences of tendon elasticity are summarized with respect to exercise performance under mechanically and neurally controlled joint actions, which lead to energy saving of muscle fibers and enhancing the positive work of the muscle. 3) The task-specificity of the muscle as an actuator or a spring and its position dependence (proximal to distal trend of functional divergence) are mentioned. Literature shows that proximal muscles are architecturally designed for actuation and distal muscles are more suited for a spring function. 4) Unique but strange behavior of tendinous tissues, that is seen in stretch-shortening types of movement, is described, suggesting variable elasticity of tendinous tissues that is modulated by muscle activation. 5) Finally, a need to consider multiple muscle-tendon units as a system is introduced to reasonably understand recent findings that otherwise cannot be accounted for. Collectively, it is suggested that the muscle-tendon unit is not only a simple combination of muscle fiber and tendinous tissues acting as actuator and spring, respectively, but also a unit that acts both anatomically and functionally.
- 著者
- Kazuhiko Higashida Izumi Tabata Mitsuru Higuchi Shin Terada
- 出版者
- 一般社団法人日本体力医学会
- 雑誌
- The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)
- 巻号頁・発行日
- vol.2, no.3, pp.355-360, 2013-08-25 (Released:2013-09-08)
- 参考文献数
- 42
- 被引用文献数
- 1 1
Skeletal muscle is the primary site of glucose uptake in humans. Glucose transport activity, which is the rate-limiting step in muscle glucose metabolism, is linearly related to the content of the GLUT-4 isoform of the glucose transporter. Therefore, the level of GLUT-4 in skeletal muscle may be an important determinant of whole-body glucose disposal. It has been well documented that long-term, low- to moderate-intensity endurance exercise training induces an increase in muscle GLUT-4 content. However, emerging evidence suggests that an adaptive increase in GLUT-4 occurs even after a single acute bout of exercise or high-intensity intermittent exercise training. Recent findings also indicate that nutritional status affects GLUT-4 expression in skeletal muscle. This review provides an overview of the effects of exercise and nutritional status on GLUT-4 content in skeletal muscle, and summarizes recent progress in elucidating the molecular regulation of muscle GLUT-4 gene expression by exercise and nutritional stimuli.
- 著者
- Tsuneo Watanabe Nobuo Terabayashi Bateer Shi Sohee Shin Kosho Kasuga Tamotsu Yabumoto Katsuji Shimizu Toshio Matsuoka
- 出版者
- 一般社団法人日本体力医学会
- 雑誌
- The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)
- 巻号頁・発行日
- vol.2, no.2, pp.243-250, 2013-05-25 (Released:2013-06-21)
- 参考文献数
- 24
- 被引用文献数
- 1 3
The purpose of this study was to investigate the influence of cryotherapy on knee joint position sense (JPS) and intraarticular blood flow volume (IBFV) and evaluate their relationships with cooling time as well as with surface temperature and deep temperature. Ten healthy volunteers were examined. This study consisted of a same-subjects repeated-measures design, with the timeframe of cryotherapy application (no therapy [resting control group], 2-min cooling, or 15-min cooling intervention) after exercise being the independent variable, and IBFV, knee JPS, surface temperature, and deep temperature serving as the dependent variables. Dependent variables were examined before 10-min cycle ergometer exercise (baseline), post-exercise, post-cooling, and 15 min later. In the 15-min cooling group, IBFV immediately after cooling and 15 min later were significantly lower than the post-exercise values (P = 0.048 and 0.016, respectively), and knee JPS at 15 min later was significantly lower than the baseline value (P = 0.037). By contrast, the 2-min cooling group showed no significant changes in either knee JPS or IBFV. Although both surface and deep temperatures after cooling were significantly lower than baseline (P = 0.034 and P < 0.001, respectively) in the 2-min cooling group, 15 min later they were significantly higher than post-cooling values (P = 0.023 and 0.023, respectively). These results suggest that 15-min cooling interventions functionally impair the sensitivity of JPS, although cooling is suitable for reduction of IBFV in deep tissue. Cooling interventions lasting less than 2-min did not affect knee JPS; however no reduction of IBFV occurred during this timeframe.