2022/12/08 更新

写真a

スズキ シュウジ
鈴木 秀次
所属
人間科学学術院
職名
名誉教授

学歴

  •  
    -
    1975年

    ワシントン大学   体育学   運動制御  

  •  
    -
    1975年

    The University of Washington   Graduate School, Division of Physical Education   Motor control  

  •  
    -
    1970年

    早稲田大学   教育学部   体育学  

  •  
    -
    1970年

    早稲田大学  

学位

  • 千葉大学   医学博士

  • ワシントン大学   MS

経歴

  • 1996年
    -
     

    - 早稲田大学人間科学部 教授(現在に至る)

  • 1996年
    -
     

    - School of Human Sciences,

  • 1991年
    -
    1996年

    早稲田大学人間科学部 助教授

  • 1991年
    -
    1996年

    School of Human Sciences,

  • 1987年
    -
    1991年

    早稲田大学人間科学部 講師

  • 1987年
    -
    1991年

    School of Human Sciences,

  • 1985年
    -
    1987年

    杏林大学医学部 講師

  • 1985年
    -
    1987年

    杏林大学

  • 1980年
    -
    1985年

    杏林大学医学部 助手

  • 1980年
    -
    1985年

    杏林大学

  •  
     
     

    早稲田大学

  •  
     
     

    早稲田大学

  •  
     
     

    早稲田大学

  •  
     
     

    Assistant Professor

  •  
     
     

    Research Assistant

▼全件表示

所属学協会

  •  
     
     

    日本バイオメカニクス学会

  •  
     
     

    国際バイオメカニクス学会

  •  
     
     

    日本体育学会

  •  
     
     

    国際電気生理運動学会

  •  
     
     

    日本電気生理運動学会

  •  
     
     

    日本体力医学会

  •  
     
     

    アメリカスポーツ医学会

  •  
     
     

    日本神経科学学会

  •  
     
     

    日本生理学会

  •  
     
     

    Japanese Society of Biomechanics

  •  
     
     

    International Society of Biomechanics

  •  
     
     

    International Society of Electrophysiology and Kinesiology

  •  
     
     

    Japanese Society of Electrophysiology and Kinesiology

  •  
     
     

    Japanese Society of Physical Fitness and Exercise

  •  
     
     

    American College of Sports Medicine

  •  
     
     

    Japan Neurosience Society

  •  
     
     

    Japanese Physiological Society

▼全件表示

 

研究分野

  • 医療薬学

  • 神経科学一般

  • 生理学

  • 神経科学一般

研究キーワード

  • 体力科学

  • バイオメカニクス

  • 身体運動科学

  • 運動制御

  • 神経・筋肉生理学

  • Physical fitness

  • Biomechanics

  • Neuromuscular control

▼全件表示

書籍等出版物

  • 「健康福祉」人間科学-健康福祉バイオメカニクス-

    朝倉書店  2008年 ISBN: 9784254505283

Misc

  • A Japanese stretching intervention can modify lumbar lordosis curvature

    Kadono N, Tsuchiya K, Uematsu A, Kamoshita T, Kiryu K, Hortobágyi T, Suzuki S

    Journal of Spinal Disorders and Techniques   in press  2015年

  • A Japanese stretching intervention can modify lumbar lordosis curvature

    Kadono N, Tsuchiya K, Uematsu A, Kamoshita T, Kiryu K, Hortobágyi T, Suzuki S

    Journal of Spinal Disorders and Techniques   in press  2015年

  • A Behavioral Mechanism of How Increases in Leg Strength Improve Old Adults' Gait Speed

    Azusa Uematsu, Kazushi Tsuchiya, Norio Kadono, Hirofumi Kobayashi, Takamasa Kaetsu, Tibor Hortobagyi, Shuji Suzuki

    PLOS ONE   9 ( 10 )  2014年10月

     概要を見る

    We examined a behavioral mechanism of how increases in leg strength improve healthy old adults' gait speed. Leg press strength training improved maximal leg press load 40% (p = 0.001) and isometric strength in 5 group of leg muscles 32% (p = 0.001) in a randomly allocated intervention group of healthy old adults (age 74, n = 15) but not in no-exercise control group (age 74, n = 8). Gait speed increased similarly in the training (9.9%) and control (8.6%) groups (time main effect, p = 0.001). However, in the training group only, in line with the concept of biomechanical plasticity of aging gait, hip extensors and ankle plantarflexors became the only significant predictors of self-selected and maximal gait speed. The study provides the first behavioral evidence regarding a mechanism of how increases in leg strength improve healthy old adults' gait speed.

    DOI

  • A Behavioral Mechanism of How Increases in Leg Strength Improve Old Adults' Gait Speed

    Azusa Uematsu, Kazushi Tsuchiya, Norio Kadono, Hirofumi Kobayashi, Takamasa Kaetsu, Tibor Hortobagyi, Shuji Suzuki

    PLOS ONE   9 ( 10 )  2014年10月

     概要を見る

    We examined a behavioral mechanism of how increases in leg strength improve healthy old adults' gait speed. Leg press strength training improved maximal leg press load 40% (p = 0.001) and isometric strength in 5 group of leg muscles 32% (p = 0.001) in a randomly allocated intervention group of healthy old adults (age 74, n = 15) but not in no-exercise control group (age 74, n = 8). Gait speed increased similarly in the training (9.9%) and control (8.6%) groups (time main effect, p = 0.001). However, in the training group only, in line with the concept of biomechanical plasticity of aging gait, hip extensors and ankle plantarflexors became the only significant predictors of self-selected and maximal gait speed. The study provides the first behavioral evidence regarding a mechanism of how increases in leg strength improve healthy old adults' gait speed.

    DOI

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults

    H. Kobayashi, Y. Koyama, R. M. Enoka, S. Suzuki

    SCANDINAVIAN JOURNAL OF MEDICINE & SCIENCE IN SPORTS   24 ( 1 ) 98 - 110  2014年02月

     概要を見る

    Beginning Movement Load (BML) training is a unique form of light-load training that comprises a lengthening-shortening sequence of muscle actions about multiple degrees of freedom. The purpose of the study was to determine the effectiveness of BML training at improving the performance of old adults on four functional tasks and to identify some of the neuromuscular adaptations that contributed to these gains. Healthy old adults (67.5 +/- 5.23 years) were randomly assigned to either a BML training group (n=17) or a control group (n=7). The training group exercised with a 30% of the one repetition-maximum (1-RM) load and performed five to seven sets of 15 repetitions, three times per week for 8 weeks. BML training increased maximal voluntary contraction (MVC) force significantly for the knee extensors (31.6%), but not the elbow flexors (9.8%), and improved the steadiness of isometric contractions (10%, 30%, and 65% MVC forces). Training-associated changes in times for ascending and descending stairs and one-legged balance, but not the chair rise, were predicted by changes in selected combinations of MVC force and steadiness. The attributes of BML training that enabled it to elicit functionally meaningful adaptations in the neuromuscular system of older adults should be explored with more mechanistic studies.

    DOI

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults

    H. Kobayashi, Y. Koyama, R. M. Enoka, S. Suzuki

    Scandinavian Journal of Medicine and Science in Sports   24 ( 1 ) 98 - 110  2014年02月

     概要を見る

    Beginning Movement Load (BML) training is a unique form of light-load training that comprises a lengthening-shortening sequence of muscle actions about multiple degrees of freedom. The purpose of the study was to determine the effectiveness of BML training at improving the performance of old adults on four functional tasks and to identify some of the neuromuscular adaptations that contributed to these gains. Healthy old adults (67.5±5.23 years) were randomly assigned to either a BML training group (n=17) or a control group (n=7). The training group exercised with a 30% of the one repetition-maximum (1-RM) load and performed five to seven sets of 15 repetitions, three times per week for 8 weeks. BML training increased maximal voluntary contraction (MVC) force significantly for the knee extensors (31.6%), but not the elbow flexors (9.8%), and improved the steadiness of isometric contractions (10%, 30%, and 65% MVC forces). Training-associated changes in times for ascending and descending stairs and one-legged balance, but not the chair rise, were predicted by changes in selected combinations of MVC force and steadiness. The attributes of BML training that enabled it to elicit functionally meaningful adaptations in the neuromuscular system of older adults should be explored with more mechanistic studies. © 2012 John Wiley &amp
    Sons A/S. Published by John Wiley &amp
    Sons Ltd.

    DOI PubMed

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults

    H. Kobayashi, Y. Koyama, R. M. Enoka, S. Suzuki

    SCANDINAVIAN JOURNAL OF MEDICINE & SCIENCE IN SPORTS   24 ( 1 ) 98 - 110  2014年02月

     概要を見る

    Beginning Movement Load (BML) training is a unique form of light-load training that comprises a lengthening-shortening sequence of muscle actions about multiple degrees of freedom. The purpose of the study was to determine the effectiveness of BML training at improving the performance of old adults on four functional tasks and to identify some of the neuromuscular adaptations that contributed to these gains. Healthy old adults (67.5 +/- 5.23 years) were randomly assigned to either a BML training group (n=17) or a control group (n=7). The training group exercised with a 30% of the one repetition-maximum (1-RM) load and performed five to seven sets of 15 repetitions, three times per week for 8 weeks. BML training increased maximal voluntary contraction (MVC) force significantly for the knee extensors (31.6%), but not the elbow flexors (9.8%), and improved the steadiness of isometric contractions (10%, 30%, and 65% MVC forces). Training-associated changes in times for ascending and descending stairs and one-legged balance, but not the chair rise, were predicted by changes in selected combinations of MVC force and steadiness. The attributes of BML training that enabled it to elicit functionally meaningful adaptations in the neuromuscular system of older adults should be explored with more mechanistic studies.

    DOI

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults

    H. Kobayashi, Y. Koyama, R. M. Enoka, S. Suzuki

    SCANDINAVIAN JOURNAL OF MEDICINE & SCIENCE IN SPORTS   24 ( 1 ) 98 - 110  2014年02月

     概要を見る

    Beginning Movement Load (BML) training is a unique form of light-load training that comprises a lengthening-shortening sequence of muscle actions about multiple degrees of freedom. The purpose of the study was to determine the effectiveness of BML training at improving the performance of old adults on four functional tasks and to identify some of the neuromuscular adaptations that contributed to these gains. Healthy old adults (67.5 +/- 5.23 years) were randomly assigned to either a BML training group (n=17) or a control group (n=7). The training group exercised with a 30% of the one repetition-maximum (1-RM) load and performed five to seven sets of 15 repetitions, three times per week for 8 weeks. BML training increased maximal voluntary contraction (MVC) force significantly for the knee extensors (31.6%), but not the elbow flexors (9.8%), and improved the steadiness of isometric contractions (10%, 30%, and 65% MVC forces). Training-associated changes in times for ascending and descending stairs and one-legged balance, but not the chair rise, were predicted by changes in selected combinations of MVC force and steadiness. The attributes of BML training that enabled it to elicit functionally meaningful adaptations in the neuromuscular system of older adults should be explored with more mechanistic studies.

    DOI

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults

    H. Kobayashi, Y. Koyama, R. M. Enoka, S. Suzuki

    SCANDINAVIAN JOURNAL OF MEDICINE & SCIENCE IN SPORTS   24 ( 1 ) 98 - 110  2014年02月

     概要を見る

    Beginning Movement Load (BML) training is a unique form of light-load training that comprises a lengthening-shortening sequence of muscle actions about multiple degrees of freedom. The purpose of the study was to determine the effectiveness of BML training at improving the performance of old adults on four functional tasks and to identify some of the neuromuscular adaptations that contributed to these gains. Healthy old adults (67.5 +/- 5.23 years) were randomly assigned to either a BML training group (n=17) or a control group (n=7). The training group exercised with a 30% of the one repetition-maximum (1-RM) load and performed five to seven sets of 15 repetitions, three times per week for 8 weeks. BML training increased maximal voluntary contraction (MVC) force significantly for the knee extensors (31.6%), but not the elbow flexors (9.8%), and improved the steadiness of isometric contractions (10%, 30%, and 65% MVC forces). Training-associated changes in times for ascending and descending stairs and one-legged balance, but not the chair rise, were predicted by changes in selected combinations of MVC force and steadiness. The attributes of BML training that enabled it to elicit functionally meaningful adaptations in the neuromuscular system of older adults should be explored with more mechanistic studies.

    DOI

  • Interaction Between Thorax, Lumbar, and Pelvis Movements in the Transverse Plane During Gait at Three Velocities

    Ya-Ting Yang, Yasuyuki Yoshida, Tibor Hortobagyi, Shuji Suzuki

    JOURNAL OF APPLIED BIOMECHANICS   29 ( 3 ) 261 - 269  2013年06月

     概要を見る

    We determined the angular range of motion and the relative timing of displacement in the thorax, lumbar spine, and pelvis in the transverse plane during treadmill walking at three velocities. Nine healthy young females walked on a treadmill for three minutes at 0.40, 0.93, and 1.47 m/s. The position of seven reflective markers and three rigs placed on the thorax, lumbar spine, and pelvis were recorded at 200 Hz by an eight-camera motion capture system. As gait velocity increased, stride length increased, cycle time decreased, and angular displacement in the thorax and L1 decreased but increased at the pelvis and L5 (all P < .05). The time of maximal angular rotation occurred in the following sequence: pelvis, L5, L3, L1, and thorax (P < .001). The thorax and L1 and L3 were in-phase for shorter duration as gait velocity increased, and this reduction was especially large, approx. 32% (P < .05), between thorax and pelvis. As gait velocity increased, the pelvis rotated earlier, causing the shortening of in-phase duration between thorax and pelvis. These data suggest that, as gait velocity increases, pelvis rotation dictates trunk rotation in the transverse plane during gait in healthy young females.

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane during gait at three velocities

    Ya-Ting Yang, Yasuyuki Yoshida, Tibor Hortobágyi, Shuji Suzuki

    Journal of Applied Biomechanics   29 ( 3 ) 261 - 269  2013年

     概要を見る

    We determined the angular range of motion and the relative timing of displacement in the thorax, lumbar spine, and pelvis in the transverse plane during treadmill walking at three velocities. Nine healthy young females walked on a treadmill for three minutes at 0.40, 0.93, and 1.47 m/s. The position of seven reflective markers and three rigs placed on the thorax, lumbar spine, and pelvis were recorded at 200 Hz by an eight-camera motion capture system. As gait velocity increased, stride length increased, cycle time decreased, and angular displacement in the thorax and L1 decreased but increased at the pelvis and L5 (all P &lt
    .05). The time of maximal angular rotation occurred in the following sequence: pelvis, L5, L3, L1, and thorax (P &lt
    .001). The thorax and L1 and L3 were in-phase for shorter duration as gait velocity increased, and this reduction was especially large, approx. 32% (P &lt
    .05), between thorax and pelvis. As gait velocity increased, the pelvis rotated earlier, causing the shortening of in-phase duration between thorax and pelvis. These data suggest that, as gait velocity increases, pelvis rotation dictates trunk rotation in the transverse plane during gait in healthy young females. © 2013 Human Kinetics, Inc.

    DOI

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   29 ( 3 )  2013年

  • Lumbar lordosis angle (LLA) and leg strength predict walking ability in elderly males

    Junya Miyazaki, Shin Murata, Jun Horie, Azusa Uematsu, Tibor Hortobagyi, Shuji Suzuki

    ARCHIVES OF GERONTOLOGY AND GERIATRICS   56 ( 1 ) 141 - 147  2013年01月

     概要を見る

    There is an association between gait performance and spinal alignment in elderly females but it is unclear if this association is gender-dependent and postural changes would also predict gait performance in healthy elderly males. We measured thoracic kyphosis angle (TKA), LLA as indices of spinal alignment and maximal walking speed (WS), timed up and go test (TUG), 10-m obstacle walking time, and 6-min walk distance as indices of gait performance in healthy old males (n = 124, age 73.0 +/- 7.2 years). Knee extensor strength and one-leg standing time with eyes open were measures of physical function. The LLA but not TKA correlated with performance in each of the 4 gait test. Multiple-regression analyses showed that only the combination of knee extensor strength and LLA accounted for significant variation in gait performance. While previous studies showed that spinal alignment is associated with gait performance in elderly women, in healthy elderly males both functional (leg strength) and structural (spinal alignment) factors contribute to gait performance. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

    DOI PubMed

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   29 ( 3 )  2013年

  • Lumbar lordosis angle (LLA) and leg strength predict walking ability in elderly males

    Junya Miyazaki, Shin Murata, Jun Horie, Azusa Uematsu, Tibor Hortobagyi, Shuji Suzuki

    ARCHIVES OF GERONTOLOGY AND GERIATRICS   56 ( 1 ) 141 - 147  2013年01月

     概要を見る

    There is an association between gait performance and spinal alignment in elderly females but it is unclear if this association is gender-dependent and postural changes would also predict gait performance in healthy elderly males. We measured thoracic kyphosis angle (TKA), LLA as indices of spinal alignment and maximal walking speed (WS), timed up and go test (TUG), 10-m obstacle walking time, and 6-min walk distance as indices of gait performance in healthy old males (n = 124, age 73.0 +/- 7.2 years). Knee extensor strength and one-leg standing time with eyes open were measures of physical function. The LLA but not TKA correlated with performance in each of the 4 gait test. Multiple-regression analyses showed that only the combination of knee extensor strength and LLA accounted for significant variation in gait performance. While previous studies showed that spinal alignment is associated with gait performance in elderly women, in healthy elderly males both functional (leg strength) and structural (spinal alignment) factors contribute to gait performance. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

    DOI PubMed

  • Lumbar lordosis angle (LLA) and leg strength predict walking ability in elderly males

    Junya Miyazaki, Shin Murata, Jun Horie, Azusa Uematsu, Tibor Hortobagyi, Shuji Suzuki

    ARCHIVES OF GERONTOLOGY AND GERIATRICS   56 ( 1 ) 141 - 147  2013年01月

     概要を見る

    There is an association between gait performance and spinal alignment in elderly females but it is unclear if this association is gender-dependent and postural changes would also predict gait performance in healthy elderly males. We measured thoracic kyphosis angle (TKA), LLA as indices of spinal alignment and maximal walking speed (WS), timed up and go test (TUG), 10-m obstacle walking time, and 6-min walk distance as indices of gait performance in healthy old males (n = 124, age 73.0 +/- 7.2 years). Knee extensor strength and one-leg standing time with eyes open were measures of physical function. The LLA but not TKA correlated with performance in each of the 4 gait test. Multiple-regression analyses showed that only the combination of knee extensor strength and LLA accounted for significant variation in gait performance. While previous studies showed that spinal alignment is associated with gait performance in elderly women, in healthy elderly males both functional (leg strength) and structural (spinal alignment) factors contribute to gait performance. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Lumbar lordosis angle (LLA) and leg strength predict walking ability in elderly males

    Junya Miyazaki, Shin Murata, Jun Horie, Azusa Uematsu, Tibor Hortobagyi, Shuji Suzuki

    ARCHIVES OF GERONTOLOGY AND GERIATRICS   56 ( 1 ) 141 - 147  2013年01月

     概要を見る

    There is an association between gait performance and spinal alignment in elderly females but it is unclear if this association is gender-dependent and postural changes would also predict gait performance in healthy elderly males. We measured thoracic kyphosis angle (TKA), LLA as indices of spinal alignment and maximal walking speed (WS), timed up and go test (TUG), 10-m obstacle walking time, and 6-min walk distance as indices of gait performance in healthy old males (n = 124, age 73.0 +/- 7.2 years). Knee extensor strength and one-leg standing time with eyes open were measures of physical function. The LLA but not TKA correlated with performance in each of the 4 gait test. Multiple-regression analyses showed that only the combination of knee extensor strength and LLA accounted for significant variation in gait performance. While previous studies showed that spinal alignment is associated with gait performance in elderly women, in healthy elderly males both functional (leg strength) and structural (spinal alignment) factors contribute to gait performance. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Different modulation pattern of spinal stretch reflex excitability in highly trained endurance runners

    Tetsuya Ogawa, Noritaka Kawashima, Shuji Suzuki, Kimitaka Nakazawa

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   112 ( 10 ) 3641 - 3648  2012年10月

     概要を見る

    This study was undertaken to elucidate the impact of long-term physical training on the modulation of stretch reflex excitability. To this end, electromyographic activities of the soleus muscle in response to quick toe-up rotation were compared between highly trained endurance runners (n = 8) and non-trained control subjects (n = 9). We specifically focused on the stretch reflex modulation under different voluntary activation levels, from rest to pre-activated conditions (5, 10, 20, and 30% of the maximal). While the two groups showed similar modulation patterns of the stretch reflex responses, the extent of reflex modulation in accordance with the muscle pre-activation level was larger in the trained group. The present results therefore suggest a different modulation pattern of the stretch reflex responses with changing activation level between individuals with different physical background, and the enhancement of the responses in the trained individuals may particularly be advantageous in exerting high level muscle contraction.

    DOI PubMed

  • Different modulation pattern of spinal stretch reflex excitability in highly trained endurance runners

    Tetsuya Ogawa, Noritaka Kawashima, Shuji Suzuki, Kimitaka Nakazawa

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   112 ( 10 ) 3641 - 3648  2012年10月

     概要を見る

    This study was undertaken to elucidate the impact of long-term physical training on the modulation of stretch reflex excitability. To this end, electromyographic activities of the soleus muscle in response to quick toe-up rotation were compared between highly trained endurance runners (n = 8) and non-trained control subjects (n = 9). We specifically focused on the stretch reflex modulation under different voluntary activation levels, from rest to pre-activated conditions (5, 10, 20, and 30% of the maximal). While the two groups showed similar modulation patterns of the stretch reflex responses, the extent of reflex modulation in accordance with the muscle pre-activation level was larger in the trained group. The present results therefore suggest a different modulation pattern of the stretch reflex responses with changing activation level between individuals with different physical background, and the enhancement of the responses in the trained individuals may particularly be advantageous in exerting high level muscle contraction.

    DOI PubMed

  • 人はいかにして速く走るのか―100m走の最新サイエンス

    鈴木秀次

    ミルシル 国立科学博物館   5 ( 4 ) 10 - 13  2012年

  • Mechanisms of post-contraction activation in skeletal muscle

    Uematsu A, Sekiguchi H, Kobayashi H, Tsuchiya K, Hortobagyi T, Suzuki S

    The Journal of Physical Fitness and Sports Medicine   1 ( 3 ) 513 - 521  2012年

    DOI

  • Mechanisms of post-contraction activation in skeletal muscle

    Uematsu A, Sekiguchi H, Kobayashi H, Tsuchiya K, Hortobagyi T, Suzuki S

    The Journal of Physical Fitness and Sports Medicine   1 ( 3 ) 513 - 521  2012年

    DOI

  • Asymmetrical Neural Adaptation in Lower Leg Muscles as a Consequence of Stereotypical Motor Training

    Tetsuya Ogawa, Noritaka Kawashima, Shuji Suzuki, Kimitaka Nakazawa

    JOURNAL OF MOTOR BEHAVIOR   44 ( 1 ) 63 - 68  2012年

     概要を見る

    Despite well-authorized facts regarding asymmetrical architectural changes between different limbs after persistent participation in particular motor training, no studies have addressed the neural aspects to the present. The authors undertook the study to elucidate the possibility of neural adaptation on a limb-by-limb basis after repetitive engagement in a particular motor training routine. We investigated lower leg muscles in endurance-trained track runners who have been trained by routinely running on a track in counterclockwise direction on curved paths. Stretch reflex responses in the plantarflexor muscles (soleus [SOL], medial [MG], and lateral head of the gastrocnemius muscle) were evaluated bilaterally with participants sitting at rest. Comparisons were made between homonymous muscles of the right (corresponding to outside leg for track running) and left leg (inside leg, likewise) and with a group of nontrained controls. The result clearly demonstrated that the responses were prominently different between the legs (thus, asymmetrical) in the MG muscles and partially in the SOL muscles in the trained group. In contrast, no such differences were obtained in the nontrained control group. The result demonstrated that neural adaptation took place asymmetrically and that could be attributable to their repetitive engagement in the stereotypical motor task.

    DOI

  • Asymmetrical Neural Adaptation in Lower Leg Muscles as a Consequence of Stereotypical Motor Training

    Tetsuya Ogawa, Noritaka Kawashima, Shuji Suzuki, Kimitaka Nakazawa

    JOURNAL OF MOTOR BEHAVIOR   44 ( 1 ) 63 - 68  2012年

     概要を見る

    Despite well-authorized facts regarding asymmetrical architectural changes between different limbs after persistent participation in particular motor training, no studies have addressed the neural aspects to the present. The authors undertook the study to elucidate the possibility of neural adaptation on a limb-by-limb basis after repetitive engagement in a particular motor training routine. We investigated lower leg muscles in endurance-trained track runners who have been trained by routinely running on a track in counterclockwise direction on curved paths. Stretch reflex responses in the plantarflexor muscles (soleus [SOL], medial [MG], and lateral head of the gastrocnemius muscle) were evaluated bilaterally with participants sitting at rest. Comparisons were made between homonymous muscles of the right (corresponding to outside leg for track running) and left leg (inside leg, likewise) and with a group of nontrained controls. The result clearly demonstrated that the responses were prominently different between the legs (thus, asymmetrical) in the MG muscles and partially in the SOL muscles in the trained group. In contrast, no such differences were obtained in the nontrained control group. The result demonstrated that neural adaptation took place asymmetrically and that could be attributable to their repetitive engagement in the stereotypical motor task.

    DOI

  • Preferred step frequency minimizes veering during natural human walking

    Azusa Uematsu, Koh Inoue, Hiroaki Hobara, Hirofumi Kobayashi, Yuki Iwamoto, Tibor Hortobagyi, Shuji Suzuki

    NEUROSCIENCE LETTERS   505 ( 3 ) 291 - 293  2011年11月

     概要を見る

    In the absence of visual information, humans cannot maintain a straight walking path. We examined the hypothesis that step frequency during walking affects the magnitude of veering in healthy adults. Subject walked at a preferred (1.77 +/- 0.18 Hz), low (0.8 x preferred, 1.41 +/- 0.15 Hz), and high (1.2 x preferred, 2.13 +/- 0.20 Hz) step frequency with and without a blindfold. We compared the absolute differences between estimated and measured points of crossing a target line after 16 m of forward walking at the three step frequencies. There was no significant difference in veering when subjects walked at the different frequencies without a blindfold. However, the magnitude of veering was the smallest at the preferred (mean +/- SE = 91.6 +/- 33.6 cm) compared with the low (204.3 +/- 43.0 cm) and high (112.7 +/- 34.0 cm) frequency gaits with a blindfold. Thus, walking at a preferred step frequency minimizes veering, which occurs in the absence of visual information. This phenomenon may be associated with the previously reported minimization of movement variability, energy cost, and attentional demand while walking at a preferred step frequency. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

    DOI PubMed

  • Preferred step frequency minimizes veering during natural human walking

    Azusa Uematsu, Koh Inoue, Hiroaki Hobara, Hirofumi Kobayashi, Yuki Iwamoto, Tibor Hortobagyi, Shuji Suzuki

    NEUROSCIENCE LETTERS   505 ( 3 ) 291 - 293  2011年11月

     概要を見る

    In the absence of visual information, humans cannot maintain a straight walking path. We examined the hypothesis that step frequency during walking affects the magnitude of veering in healthy adults. Subject walked at a preferred (1.77 +/- 0.18 Hz), low (0.8 x preferred, 1.41 +/- 0.15 Hz), and high (1.2 x preferred, 2.13 +/- 0.20 Hz) step frequency with and without a blindfold. We compared the absolute differences between estimated and measured points of crossing a target line after 16 m of forward walking at the three step frequencies. There was no significant difference in veering when subjects walked at the different frequencies without a blindfold. However, the magnitude of veering was the smallest at the preferred (mean +/- SE = 91.6 +/- 33.6 cm) compared with the low (204.3 +/- 43.0 cm) and high (112.7 +/- 34.0 cm) frequency gaits with a blindfold. Thus, walking at a preferred step frequency minimizes veering, which occurs in the absence of visual information. This phenomenon may be associated with the previously reported minimization of movement variability, energy cost, and attentional demand while walking at a preferred step frequency. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

    DOI PubMed

  • Preferred step frequency minimizes veering during natural human walking

    Azusa Uematsu, Koh Inoue, Hiroaki Hobara, Hirofumi Kobayashi, Yuki Iwamoto, Tibor Hortobagyi, Shuji Suzuki

    NEUROSCIENCE LETTERS   505 ( 3 ) 291 - 293  2011年11月

     概要を見る

    In the absence of visual information, humans cannot maintain a straight walking path. We examined the hypothesis that step frequency during walking affects the magnitude of veering in healthy adults. Subject walked at a preferred (1.77 +/- 0.18 Hz), low (0.8 x preferred, 1.41 +/- 0.15 Hz), and high (1.2 x preferred, 2.13 +/- 0.20 Hz) step frequency with and without a blindfold. We compared the absolute differences between estimated and measured points of crossing a target line after 16 m of forward walking at the three step frequencies. There was no significant difference in veering when subjects walked at the different frequencies without a blindfold. However, the magnitude of veering was the smallest at the preferred (mean +/- SE = 91.6 +/- 33.6 cm) compared with the low (204.3 +/- 43.0 cm) and high (112.7 +/- 34.0 cm) frequency gaits with a blindfold. Thus, walking at a preferred step frequency minimizes veering, which occurs in the absence of visual information. This phenomenon may be associated with the previously reported minimization of movement variability, energy cost, and attentional demand while walking at a preferred step frequency. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Preferred step frequency minimizes veering during natural human walking

    Azusa Uematsu, Koh Inoue, Hiroaki Hobara, Hirofumi Kobayashi, Yuki Iwamoto, Tibor Hortobagyi, Shuji Suzuki

    NEUROSCIENCE LETTERS   505 ( 3 ) 291 - 293  2011年11月

     概要を見る

    In the absence of visual information, humans cannot maintain a straight walking path. We examined the hypothesis that step frequency during walking affects the magnitude of veering in healthy adults. Subject walked at a preferred (1.77 +/- 0.18 Hz), low (0.8 x preferred, 1.41 +/- 0.15 Hz), and high (1.2 x preferred, 2.13 +/- 0.20 Hz) step frequency with and without a blindfold. We compared the absolute differences between estimated and measured points of crossing a target line after 16 m of forward walking at the three step frequencies. There was no significant difference in veering when subjects walked at the different frequencies without a blindfold. However, the magnitude of veering was the smallest at the preferred (mean +/- SE = 91.6 +/- 33.6 cm) compared with the low (204.3 +/- 43.0 cm) and high (112.7 +/- 34.0 cm) frequency gaits with a blindfold. Thus, walking at a preferred step frequency minimizes veering, which occurs in the absence of visual information. This phenomenon may be associated with the previously reported minimization of movement variability, energy cost, and attentional demand while walking at a preferred step frequency. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • CONTRACTION HISTORY PRODUCES TASK-SPECIFIC VARIATIONS IN SPINAL EXCITABILITY IN HEALTHY HUMAN SOLEUS MUSCLE

    Azusa Uematsu, Hirofumi Sekiguchi, Hirofumi Kobayashi, Tibor Hortobagyi, Shuji Suzuki

    MUSCLE & NERVE   43 ( 6 ) 851 - 858  2011年06月

     概要を見る

    Introduction: In human movements muscles lengthen and then shorten, or occasionally shorten and then lengthen, but it is unclear whether the nature of neural activation of the initial phase influences the neural state of the subsequent phase. We examined whether contraction history modulates spinal excitability in the healthy human soleus muscle. Methods: Subjects performed six blocks of 10 repetitions of four muscle actions consisting of specific combinations of passive shortening (PAS), and passive lengthening (PAL), shortening contraction (SHO), and lengthening contraction (LEN); that is: (1) SHO+PAL; (2) PAS+LEN; (3) PAS+PAL; and (4) SHO+LEN. Results: Compared with baseline, the H-reflex increased in the block of 300-400 s after SHO+PAL and decreased in the block of 0-100 s after PAS+LEN and SHO+LEN. Conclusions: Our results suggest that spinal excitability is potentiated during a muscle action preceded by muscle shortening, but it becomes depressed during a muscle action preceded by muscle lengthening. Muscle Nerve 43: 851-858, 2011

    DOI PubMed

  • CONTRACTION HISTORY PRODUCES TASK-SPECIFIC VARIATIONS IN SPINAL EXCITABILITY IN HEALTHY HUMAN SOLEUS MUSCLE

    Azusa Uematsu, Hirofumi Sekiguchi, Hirofumi Kobayashi, Tibor Hortobagyi, Shuji Suzuki

    MUSCLE & NERVE   43 ( 6 ) 851 - 858  2011年06月

     概要を見る

    Introduction: In human movements muscles lengthen and then shorten, or occasionally shorten and then lengthen, but it is unclear whether the nature of neural activation of the initial phase influences the neural state of the subsequent phase. We examined whether contraction history modulates spinal excitability in the healthy human soleus muscle. Methods: Subjects performed six blocks of 10 repetitions of four muscle actions consisting of specific combinations of passive shortening (PAS), and passive lengthening (PAL), shortening contraction (SHO), and lengthening contraction (LEN); that is: (1) SHO+PAL; (2) PAS+LEN; (3) PAS+PAL; and (4) SHO+LEN. Results: Compared with baseline, the H-reflex increased in the block of 300-400 s after SHO+PAL and decreased in the block of 0-100 s after PAS+LEN and SHO+LEN. Conclusions: Our results suggest that spinal excitability is potentiated during a muscle action preceded by muscle shortening, but it becomes depressed during a muscle action preceded by muscle lengthening. Muscle Nerve 43: 851-858, 2011

    DOI PubMed

  • 上肢への外的負荷が上肢挙上および降下時における肩甲骨の3次元運動に与える影響

    井上恒, 矢内利政, 鈴木秀次

    東京体育学研究   2   21 - 27  2011年

  • Asymmetrical modulation of corticospinal excitability in the contracting and resting contralateral wrist flexors during unilateral shortening, lengthening and isometric contractions

    Azusa Uematsu, Hiroki Obata, Takashi Endoh, Taku Kitamura, Tibor Hortobagyi, Kimitaka Nakazawa, Shuji Suzuki

    EXPERIMENTAL BRAIN RESEARCH   206 ( 1 ) 59 - 69  2010年09月

     概要を見る

    Unilateral isometric muscle contractions increase motor-evoked potentials (MEPs) produced by transcranial magnetic stimulation not only in the contracting muscle but also in the resting contralateral homologous muscle. Corticospinal excitability in the M1 contralateral to the contracting muscle changes depending on the type of muscle contraction. Here, we investigated the possibility that corticospinal excitability in M1 ipsilateral to the contracting muscle is modulated in a contraction-type-dependent manner. To this end, we evaluated MEPs in the resting left flexor carpi radialis (FCR) during unilateral shortening, lengthening, and isometric muscle contractions of the right wrist flexors at 10, 20, and 30% of maximal isometric contraction force. To compare the effects of different unilateral contractions on MEPs between the contracting and resting sides, MEPs in the right FCR were recorded on two separate days. In a separate experiment, we investigated the contraction specificity of the crossed effect at the spinal level by recording H-reflexes from the resting left FCR during contraction of the right wrist flexors. The results showed that MEPs in the contracting right FCR were the smallest during lengthening contraction. By contrast, MEPs in the resting left FCR were the largest during lengthening contraction, whereas the H-reflex was similar in the resting left FCR during the three types of muscle contraction. These results suggest that different types of unilateral muscle contraction asymmetrically modulate MEP size in the resting contralateral homologous muscle and in the contracting muscle and that this regulation occurs at the supraspinal level.

    DOI PubMed

  • Asymmetrical modulation of corticospinal excitability in the contracting and resting contralateral wrist flexors during unilateral shortening, lengthening and isometric contractions

    Azusa Uematsu, Hiroki Obata, Takashi Endoh, Taku Kitamura, Tibor Hortobagyi, Kimitaka Nakazawa, Shuji Suzuki

    EXPERIMENTAL BRAIN RESEARCH   206 ( 1 ) 59 - 69  2010年09月

     概要を見る

    Unilateral isometric muscle contractions increase motor-evoked potentials (MEPs) produced by transcranial magnetic stimulation not only in the contracting muscle but also in the resting contralateral homologous muscle. Corticospinal excitability in the M1 contralateral to the contracting muscle changes depending on the type of muscle contraction. Here, we investigated the possibility that corticospinal excitability in M1 ipsilateral to the contracting muscle is modulated in a contraction-type-dependent manner. To this end, we evaluated MEPs in the resting left flexor carpi radialis (FCR) during unilateral shortening, lengthening, and isometric muscle contractions of the right wrist flexors at 10, 20, and 30% of maximal isometric contraction force. To compare the effects of different unilateral contractions on MEPs between the contracting and resting sides, MEPs in the right FCR were recorded on two separate days. In a separate experiment, we investigated the contraction specificity of the crossed effect at the spinal level by recording H-reflexes from the resting left FCR during contraction of the right wrist flexors. The results showed that MEPs in the contracting right FCR were the smallest during lengthening contraction. By contrast, MEPs in the resting left FCR were the largest during lengthening contraction, whereas the H-reflex was similar in the resting left FCR during the three types of muscle contraction. These results suggest that different types of unilateral muscle contraction asymmetrically modulate MEP size in the resting contralateral homologous muscle and in the contracting muscle and that this regulation occurs at the supraspinal level.

    DOI PubMed

  • Enhancing the weight training experience: a comparison of limb kinematics and EMG activity on three machines

    Yasushi Koyama, Hirofumi Kobayashi, Shuji Suzuki, Roger M. Enoka

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   109 ( 5 ) 789 - 801  2010年07月

     概要を見る

    The aim of the study was to compare the kinematics and the timing and amount of electromyographic (EMG) activity during the lat-pull down exercise performed on machines that afforded one, two, or three degrees of freedom for the movement. Seven healthy men (age 29.4 +/- A 5.6 years) participated in the study. The exercise was performed with a 30% 1-RM load. Three types of machines with varying degrees of freedom were used: Type 1, the conventional device that restricted the movement to a frontal plane; Type 2, the addition of forearm supination-pronation; Type 3, the addition of forearm supination-pronation and horizontal extension-flexion about the shoulder. All exercises involved a technique known as beginning movement load (BML) training in which light loads are lifted with a relaxation-lengthening-shortening sequence of muscle activation. The Type-3 machine showed: (1) the greatest vertical displacement of the wrist (p < 0.05); (2) the greatest abduction-adduction displacement about the shoulder (p < 0.01); (3) the least flexion-extension displacement about the elbow joint (p < 0.01); (4) a peak vertical velocity for the shoulder that preceded (p < 0.01) those for the elbow and then wrist during the pull-down phase; (5) a progressive proximal-to-distal sequence of EMG activation involving the serratus anterior, posterior deltoid, latissimus dorsi, and triceps brachii muscles; (6) a reversal of the roles for biceps and triceps brachii during the pull-down phase. These results suggest that BML exercises with greater degrees of freedom can enhance the association between training actions and functional activities.

    DOI PubMed CiNii

  • Enhancing the weight training experience: a comparison of limb kinematics and EMG activity on three machines

    Yasushi Koyama, Hirofumi Kobayashi, Shuji Suzuki, Roger M. Enoka

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   109 ( 5 ) 789 - 801  2010年07月

     概要を見る

    The aim of the study was to compare the kinematics and the timing and amount of electromyographic (EMG) activity during the lat-pull down exercise performed on machines that afforded one, two, or three degrees of freedom for the movement. Seven healthy men (age 29.4 +/- A 5.6 years) participated in the study. The exercise was performed with a 30% 1-RM load. Three types of machines with varying degrees of freedom were used: Type 1, the conventional device that restricted the movement to a frontal plane; Type 2, the addition of forearm supination-pronation; Type 3, the addition of forearm supination-pronation and horizontal extension-flexion about the shoulder. All exercises involved a technique known as beginning movement load (BML) training in which light loads are lifted with a relaxation-lengthening-shortening sequence of muscle activation. The Type-3 machine showed: (1) the greatest vertical displacement of the wrist (p < 0.05); (2) the greatest abduction-adduction displacement about the shoulder (p < 0.01); (3) the least flexion-extension displacement about the elbow joint (p < 0.01); (4) a peak vertical velocity for the shoulder that preceded (p < 0.01) those for the elbow and then wrist during the pull-down phase; (5) a progressive proximal-to-distal sequence of EMG activation involving the serratus anterior, posterior deltoid, latissimus dorsi, and triceps brachii muscles; (6) a reversal of the roles for biceps and triceps brachii during the pull-down phase. These results suggest that BML exercises with greater degrees of freedom can enhance the association between training actions and functional activities.

    DOI PubMed CiNii

  • Spinal Mouseを使用した脊柱彎曲角度測定の再現性

    宮崎純弥, 村田伸, 荒川千秋, 鈴木秀次

    理学療法科学   25 ( 2 ) 223 - 226  2010年

    DOI CiNii

  • Enhanced stretch reflex excitability of the soleus muscle in experienced swimmers

    Tetsuya Ogawa, Gee Hee Kim, Hirofumi Sekiguchi, Masami Akai, Shuji Suzuki, Kimitaka Nakazawa

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   105 ( 2 ) 199 - 205  2009年01月

     概要を見る

    The purpose of this study was to investigate effects of long-term participation to swimming on adaptations of spinal reflex excitability. To this end, mechanically induced stretch reflex (SR) and electrically induced Hoffmann (H-) reflex of the soleus muscle were investigated between swimmers with experience of more than 10 years and non-trained individuals while sitting at rest. The amplitude and the gain (stretch velocity vs. amplitude of the reflex response) of the SR were significantly greater in the swimming group than in the non-trained control group. Similarly, the responses of the H-reflex were also significantly greater in the swimming group than in the non-trained control group. Results of this study demonstrated that the spinal reflex excitability in experienced swimmers was far more enhanced than in non-trained individuals.

    DOI

  • Changes of joint torque during Tai Chi gait at different heights of center of body mass

    Inoue K, Kobayashi H, Uematsu A, Suzuki S

    The Impact of Technology on Sport   III   489 - 492  2009年

  • 男性高齢者の矢状面脊柱アライメントと身体機能の関係

    宮﨑純弥, 村田伸, 大田尾浩, 堀江淳, 村田潤, 鈴木秀次

    理学療法科学   24 ( 6 ) 907 - 911  2009年

    DOI CiNii

  • Enhanced stretch reflex excitability of the soleus muscle in experienced swimmers

    Tetsuya Ogawa, Gee Hee Kim, Hirofumi Sekiguchi, Masami Akai, Shuji Suzuki, Kimitaka Nakazawa

    EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY   105 ( 2 ) 199 - 205  2009年01月

     概要を見る

    The purpose of this study was to investigate effects of long-term participation to swimming on adaptations of spinal reflex excitability. To this end, mechanically induced stretch reflex (SR) and electrically induced Hoffmann (H-) reflex of the soleus muscle were investigated between swimmers with experience of more than 10 years and non-trained individuals while sitting at rest. The amplitude and the gain (stretch velocity vs. amplitude of the reflex response) of the SR were significantly greater in the swimming group than in the non-trained control group. Similarly, the responses of the H-reflex were also significantly greater in the swimming group than in the non-trained control group. Results of this study demonstrated that the spinal reflex excitability in experienced swimmers was far more enhanced than in non-trained individuals.

    DOI

  • Changes of joint torque during Tai Chi gait at different heights of center of body mass

    Inoue K, Kobayashi H, Uematsu A, Suzuki S

    The Impact of Technology on Sport   III   489 - 492  2009年

  • Tactile sensing of stiffness with fingers corresponds well with the objective elasticity evaluation

    福岡正和, 鈴木秀次

    早稲田大学人間科学研究   21 ( (2) ) 97 - 104  2008年

     概要を見る

    Original paper

    CiNii

  • 人の指による物体の硬さ知覚と客観的計測値の相関

    福岡 正和, 鈴木 秀次

    人間科学研究   21 ( (2) ) 97 - 104  2008年

     概要を見る

    Original paper

    CiNii

  • Age-related physiological and morphological changes of muscle spindles in rats

    Gee Hee Kim, Shuji Suzuki, Kenro Kanda

    JOURNAL OF PHYSIOLOGY-LONDON   582 ( 2 ) 525 - 538  2007年07月

     概要を見る

    Age-related physiological and morphological changes of muscle spindles were examined in rats (male Fischer 344/DuCrj: young, 4-13 months; middle-aged, 20-22 months; old, 28-31 months). Single afferent discharges of the muscle spindles in gastrocnemius muscles were recorded from a finely split dorsal root during ramp-and-hold (amplitude, 2.0 mm; velocity, 2-20 mm s(-1)) or sinusoidal stretch (amplitude, 0.05-1.0 mm; frequency, 0.5-2 Hz). Respective conduction velocities (CVs) were then measured. After electrophysiological experimentation, the muscles were dissected. The silver-impregnated muscle spindles were teased and then analysed using a light microscope. The CV and dynamic response to ramp-and-hold stretch of many endings were widely overlapped in old rats because of the decreased CV and dynamic response of primary endings. Many units in old rats showed slowing of discharge during the release phase under ramp-and-hold stretch and continuous discharge under sinusoidal stretch, similarly to secondary endings in young and middle-aged rats. Morphological studies revealed that primary endings of aged rat muscle spindles were less spiral or non-spiral in appearance, but secondary endings appeared unchanged. These results suggest first that primary muscle spindles in old rats are indistinguishable from secondary endings when determined solely by previously used physiological criteria. Secondly, these physiological results reflect drastic age-related morphological changes in spindle primary endings.

    DOI

  • Age-related physiological and morphological changes of muscle spindles in rats

    Gee Hee Kim, Shuji Suzuki, Kenro Kanda

    JOURNAL OF PHYSIOLOGY-LONDON   582 ( 2 ) 525 - 538  2007年07月

     概要を見る

    Age-related physiological and morphological changes of muscle spindles were examined in rats (male Fischer 344/DuCrj: young, 4-13 months; middle-aged, 20-22 months; old, 28-31 months). Single afferent discharges of the muscle spindles in gastrocnemius muscles were recorded from a finely split dorsal root during ramp-and-hold (amplitude, 2.0 mm; velocity, 2-20 mm s(-1)) or sinusoidal stretch (amplitude, 0.05-1.0 mm; frequency, 0.5-2 Hz). Respective conduction velocities (CVs) were then measured. After electrophysiological experimentation, the muscles were dissected. The silver-impregnated muscle spindles were teased and then analysed using a light microscope. The CV and dynamic response to ramp-and-hold stretch of many endings were widely overlapped in old rats because of the decreased CV and dynamic response of primary endings. Many units in old rats showed slowing of discharge during the release phase under ramp-and-hold stretch and continuous discharge under sinusoidal stretch, similarly to secondary endings in young and middle-aged rats. Morphological studies revealed that primary endings of aged rat muscle spindles were less spiral or non-spiral in appearance, but secondary endings appeared unchanged. These results suggest first that primary muscle spindles in old rats are indistinguishable from secondary endings when determined solely by previously used physiological criteria. Secondly, these physiological results reflect drastic age-related morphological changes in spindle primary endings.

    DOI

  • Changes in muscle activity with increase in leg stiffness during hopping

    Hiroaki Hobara, Kazuyuki Kanosue, Shuji Suzuki

    NEUROSCIENCE LETTERS   418 ( 1 ) 55 - 59  2007年05月

     概要を見る

    While the spring-like leg behavior of legs in mammalian locomotion has been well documented, its neural basis remains ambiguous. The purpose of the present study was to examine leg stiffness control during hopping. Seven male subjects performed in place two-legged hopping at their preferred frequency with two different contact times of the stance phase, preferred and short ones (PCT and SCT, respectively). Based on a springmass model, leg stiffness was calculated from the subjects' body mass, ground contact and flight times. Surface electromyographic (EMG) activities of the medial gastrocnemius (MG), soleus (SOL) and tibialis anterior (TA) muscles were recorded. Leg stiffness was higher in the SCT condition than in the PCT condition. The SCT condition was characterized by high EMG activity of MG and SOL at both pre- and post-landing phases, which peaked at about 50 ms. On the other hand, the activity of TA was low throughout the contact phase as compared with those of MG and SOL, and its peak value around 50 ms after landing was significantly lower for the SCT condition than for the PCT condition. We conclude that (1) the leg stiffness is regulated by a change in centrally programmed muscle preactivation and probably also by a concomitant change in the short-latency stretch reflex response of the triceps surae muscles, and (2) the co-contraction of antagonistic TA does not play a major role in leg stiffness control. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Changes in muscle activity with increase in leg stiffness during hopping

    Hiroaki Hobara, Kazuyuki Kanosue, Shuji Suzuki

    NEUROSCIENCE LETTERS   418 ( 1 ) 55 - 59  2007年05月

     概要を見る

    While the spring-like leg behavior of legs in mammalian locomotion has been well documented, its neural basis remains ambiguous. The purpose of the present study was to examine leg stiffness control during hopping. Seven male subjects performed in place two-legged hopping at their preferred frequency with two different contact times of the stance phase, preferred and short ones (PCT and SCT, respectively). Based on a springmass model, leg stiffness was calculated from the subjects' body mass, ground contact and flight times. Surface electromyographic (EMG) activities of the medial gastrocnemius (MG), soleus (SOL) and tibialis anterior (TA) muscles were recorded. Leg stiffness was higher in the SCT condition than in the PCT condition. The SCT condition was characterized by high EMG activity of MG and SOL at both pre- and post-landing phases, which peaked at about 50 ms. On the other hand, the activity of TA was low throughout the contact phase as compared with those of MG and SOL, and its peak value around 50 ms after landing was significantly lower for the SCT condition than for the PCT condition. We conclude that (1) the leg stiffness is regulated by a change in centrally programmed muscle preactivation and probably also by a concomitant change in the short-latency stretch reflex response of the triceps surae muscles, and (2) the co-contraction of antagonistic TA does not play a major role in leg stiffness control. (c) 2007 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • 外側楔状足底板および内側楔状足底板を用いた歩行の動作特性

    深野真子, 福林徹, 鈴木秀次

    体力科学   56 ( 5 ) 509 - 518  2007年

     概要を見る

    Despite their wide clinical application and success, our understanding of the effects of insoles is relatively limited. The purpose of this study was to assess the biomechanical effects of wearing lateral/medial wedged insoles on subtalar and knee joints during normal walking. Motion analysis was conducted with a 3D motion-analysis system and a ground reaction force analysis using force plate when subjects walked with three different insole conditions : 5-degree medial wedge, no wedge, and 5-degree lateral wedge. Significant differences were found in subtalar or ankle joint motion in coronal and sagittal planes compared with the no-wedge condition. No differences were found in knee joint motion in the coronal and axial planes. The lateral-wedge insole reduced the knee varus moment and increased subtalar pronation moment in mid-stance during walking. At footstrike, however, the lateral wedge increased the knee varus moment and reduced the subtalar supination moment. The medial-wedge insole increased the knee varus moment and decreased subtalar pronation moment during the mid-stance phase. However, the medial wedge reduced the knee varus moment and increased subtalar supination moment at footstrike. The results of this study indicate that the influence of the insoles varied during the stance phase. Therefore, it is requested to select the shape of insole based on the injury mechanism, the location of the pain and the injury prevention.

    DOI CiNii

  • 初動負荷トレーニング動作のバイオメカニクスと神経筋制御

    鈴木秀次, 藤森健, 吉田雅司, 小山裕史

    バイオメカニクス研究   9 ( 1 ) 26 - 33  2005年

    CiNii

  • Scapular kinematics and EMG activity of the lat pull-down with a dodge movement.

    Koyama, Y, Kobayashi, H, Suzuki, S

    Medicine & Science in Sports & Exercise   37 ( 5 ) S399  2005年

  • Scapular kinematics and EMG activity of the lat pull-down with a dodge movement.

    Koyama, Y, Kobayashi, H, Suzuki, S

    Medicine & Science in Sports & Exercise   37 ( 5 ) S399  2005年

  • Anticipatory modulation of neck muscle reflex responses induced by mechanical perturbations of the human forehead

    R Kuramochi, T Kimura, K Nakazawa, M Akai, S Torii, S Suzuki

    NEUROSCIENCE LETTERS   366 ( 2 ) 206 - 210  2004年08月

     概要を見る

    The aim of this study was to test whether anticipation of upcoming head blow stimuli, which elicit reflex responses in the neck muscle, makes the reflex responses greater or not. In nine healthy subjects the reflex responses were elicited in the sternocleidomastoid (SCM) muscle in the eyes-open (EO) and eyes-closed (EC) conditions, which corresponded to the predictable and unpredictable conditions, respectively. The subjects were instructed not to resist the perturbations after the impact. The results demonstrated that the reflex response of the SCM muscle was significantly smaller in the predictable EO condition than in the unpredictable EC condition (P < 0.05), although no significant differences were observed in either the background EMG activities or the head accelerations. Further, this effect of anticipation was observed only in the later reflex EMG component, which most probably mediated the stretch reflex pathway. In contrast, no significant difference was observed in the early component, which was presumed to be the vestibular-collic reflex. The reduced stretch reflex response was suggested to be functionally relevant to the task requirement, i.e., to let the neck extension movement occur, and not to resist after the impact of the head blow. It was concluded that the anticipation has an effect on reducing the stretch reflex responses in the neck muscle, but does not have any effect on the presumed vestibular-collic reflex under the present experimental paradigm. It is suggested that the gain of the stretch reflex pathway is modulated by anticipatory information of upcoming mechanical event. (C) 2004 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Anticipatory modulation of neck muscle reflex responses induced by mechanical perturbations of the human forehead

    R Kuramochi, T Kimura, K Nakazawa, M Akai, S Torii, S Suzuki

    NEUROSCIENCE LETTERS   366 ( 2 ) 206 - 210  2004年08月

     概要を見る

    The aim of this study was to test whether anticipation of upcoming head blow stimuli, which elicit reflex responses in the neck muscle, makes the reflex responses greater or not. In nine healthy subjects the reflex responses were elicited in the sternocleidomastoid (SCM) muscle in the eyes-open (EO) and eyes-closed (EC) conditions, which corresponded to the predictable and unpredictable conditions, respectively. The subjects were instructed not to resist the perturbations after the impact. The results demonstrated that the reflex response of the SCM muscle was significantly smaller in the predictable EO condition than in the unpredictable EC condition (P < 0.05), although no significant differences were observed in either the background EMG activities or the head accelerations. Further, this effect of anticipation was observed only in the later reflex EMG component, which most probably mediated the stretch reflex pathway. In contrast, no significant difference was observed in the early component, which was presumed to be the vestibular-collic reflex. The reduced stretch reflex response was suggested to be functionally relevant to the task requirement, i.e., to let the neck extension movement occur, and not to resist after the impact of the head blow. It was concluded that the anticipation has an effect on reducing the stretch reflex responses in the neck muscle, but does not have any effect on the presumed vestibular-collic reflex under the present experimental paradigm. It is suggested that the gain of the stretch reflex pathway is modulated by anticipatory information of upcoming mechanical event. (C) 2004 Elsevier Ireland Ltd. All rights reserved.

    DOI

  • Differences in recruitment properties of the corticospinal pathway between lengthening and shortening contractions in human soleus muscle

    H Sekiguchi, K Nakazawa, S Suzuki

    BRAIN RESEARCH   977 ( 2 ) 169 - 179  2003年07月

     概要を見る

    The purpose of this study was to investigate how the recruitment properties of the corticospinal pathway are modulated in the soleus muscle of the lower limb during lengthening (LEN) and shortening (SHO) contractions by comparing the shape of the input-output (I/O) relation of the corticospinal pathway. To this end, we investigated the relationship between various stimulus intensities applied via transcranial magnetic stimulation and the size of motor-evoked potentials in 14 healthy subjects during voluntary plantarflexion and dorsiflexion (active lengthening) with a similar background activity (BGA) level. The shape of this relationship was sigmoidal and was characterized by a plateau value, maximum slope and threshold. The plateau value was clearly lower during LEN contractions than during SHO contractions. Likewise, the maximum slope was lower during LEN contractions. However, the threshold did not differ significantly between the two tasks. Since the plateau value and the maximum slope clearly differed between LEN and SHO contractions despite the similarity of their BGA levels. the central nervous system appears to have a different activation strategy for each of these tasks. Namely, the relative balance between excitatory and inhibitory components of the corticospinal volleys, as well as the subliminal fringe of the corticospinal pathway. were reduced during LEN contractions compared with SHO contractions. These strategies may help to avoid reflexive contractions brought about by higher discharge of muscle spindles and enable fine motor actions in voluntary lengthening contractions. (C) 2003 Elsevier Science B.V. All rights reserved.

    DOI

  • Differences in recruitment properties of the corticospinal pathway between lengthening and shortening contractions in human soleus muscle

    H Sekiguchi, K Nakazawa, S Suzuki

    BRAIN RESEARCH   977 ( 2 ) 169 - 179  2003年07月

     概要を見る

    The purpose of this study was to investigate how the recruitment properties of the corticospinal pathway are modulated in the soleus muscle of the lower limb during lengthening (LEN) and shortening (SHO) contractions by comparing the shape of the input-output (I/O) relation of the corticospinal pathway. To this end, we investigated the relationship between various stimulus intensities applied via transcranial magnetic stimulation and the size of motor-evoked potentials in 14 healthy subjects during voluntary plantarflexion and dorsiflexion (active lengthening) with a similar background activity (BGA) level. The shape of this relationship was sigmoidal and was characterized by a plateau value, maximum slope and threshold. The plateau value was clearly lower during LEN contractions than during SHO contractions. Likewise, the maximum slope was lower during LEN contractions. However, the threshold did not differ significantly between the two tasks. Since the plateau value and the maximum slope clearly differed between LEN and SHO contractions despite the similarity of their BGA levels. the central nervous system appears to have a different activation strategy for each of these tasks. Namely, the relative balance between excitatory and inhibitory components of the corticospinal volleys, as well as the subliminal fringe of the corticospinal pathway. were reduced during LEN contractions compared with SHO contractions. These strategies may help to avoid reflexive contractions brought about by higher discharge of muscle spindles and enable fine motor actions in voluntary lengthening contractions. (C) 2003 Elsevier Science B.V. All rights reserved.

    DOI

  • 人はどこまで速く走れるのか?

    鈴木秀次

    新鐘/早稲田大学   69   14 - 15  2003年

  • 科学の目「走りのメカニズムとは」

    CHUMAN/中萬学院,横浜   Voice 69:3-4  2003年

  • 人はどこまで速く走れるのか?

    鈴木秀次

    新鐘/早稲田大学   69   14 - 15  2003年

  • 科学の目「走りのメカニズムとは」

    CHUMAN/中萬学院,横浜   Voice 69:3-4  2003年

  • The EMG activity and mechanics of the running jump as a function of takeoff angle

    W Kakihana, S Suzuki

    JOURNAL OF ELECTROMYOGRAPHY AND KINESIOLOGY   11 ( 5 ) 365 - 372  2001年10月

     概要を見る

    To characterize the electromyographic (EMG) activity, ground reaction forces, and kinematics were used in the running jump with different takeoff angles. Two male long jumpers volunteered to perform running jumps at different approach speeds by varying the number of steps (from 3 to 9) in the run-up. Subject TM achieved a greater vertical velocity of the center of gravity (CG) at takeoff for all approach distances. This jumping strategy was associated with greater backward trunk lean at touchdown and takeoff, a lesser range of motion for the thigh during the support phase, more extended knee and ankle angles at touchdown, and a more flexed knee angle at takeoff. Accompanying these differences in kinematics, TM experienced greater braking impulses and lesser propulsion impulses for the forward-backward component of the ground reaction force. Furthermore, TM activated mainly the rectus femoris, vastus medialis, lateral gastrocnemius, and tibialis anterior, while if rarely activated the biceps femoris from just before contact to roughly the first two-thirds of the support phase. These results indicate that TM used a greater takeoff an le in the running jump because he enabled and sustained a greater blocking effect via the coordination patterns of the muscles relative to the hip, knee, and ankle joints. These findings also suggest that the muscle activities recorded in the present experiment are reflected in kinematics and kinetics. Further, the possible influence of these muscle activities on joint movements in the takeoff leg, and their effect on the vertical and/or horizontal velocity of the jump are discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.

    DOI

  • The EMG activity and mechanics of the running jump as a function of takeoff angle

    W Kakihana, S Suzuki

    JOURNAL OF ELECTROMYOGRAPHY AND KINESIOLOGY   11 ( 5 ) 365 - 372  2001年10月

     概要を見る

    To characterize the electromyographic (EMG) activity, ground reaction forces, and kinematics were used in the running jump with different takeoff angles. Two male long jumpers volunteered to perform running jumps at different approach speeds by varying the number of steps (from 3 to 9) in the run-up. Subject TM achieved a greater vertical velocity of the center of gravity (CG) at takeoff for all approach distances. This jumping strategy was associated with greater backward trunk lean at touchdown and takeoff, a lesser range of motion for the thigh during the support phase, more extended knee and ankle angles at touchdown, and a more flexed knee angle at takeoff. Accompanying these differences in kinematics, TM experienced greater braking impulses and lesser propulsion impulses for the forward-backward component of the ground reaction force. Furthermore, TM activated mainly the rectus femoris, vastus medialis, lateral gastrocnemius, and tibialis anterior, while if rarely activated the biceps femoris from just before contact to roughly the first two-thirds of the support phase. These results indicate that TM used a greater takeoff an le in the running jump because he enabled and sustained a greater blocking effect via the coordination patterns of the muscles relative to the hip, knee, and ankle joints. These findings also suggest that the muscle activities recorded in the present experiment are reflected in kinematics and kinetics. Further, the possible influence of these muscle activities on joint movements in the takeoff leg, and their effect on the vertical and/or horizontal velocity of the jump are discussed. (C) 2001 Elsevier Science Ltd. All rights reserved.

    DOI

  • 速く走れるフォーム「日本人の体に合った走り方」

    鈴木秀次

    ゑれきてる   81   10 - 13  2001年

  • 経頭蓋磁気刺激による条件刺激が伸張性筋収縮時のヒラメ筋H反射に及ぼす効果

    関口浩文, 中澤公孝, 鈴木秀次

    ヒューマンサイエンスリサーチ   10   275 - 286  2001年

    CiNii

  • チアリーデイング競技での腰痛を誘発するキャッチ動作の特徴

    倉持梨恵子, 鈴木秀次, 鳥居俊, 渡邊裕之

    ヒューマンサイエンスリサーチ   10   241 - 252  2001年

  • 21世紀のワセダスプリント-益々の活躍を願って-

    鈴木秀次

    早稲田大学体育学研究紀要   33   3 - 10  2001年

  • 大学生アメリカンフットボール選手の頸部外傷とその発生要因

    倉持梨恵子, 鈴木秀次, 鳥居俊, 渡邊裕之

    ヒューマンサイエンスリサーチ   9   285 - 298  2000年

    CiNii

  • 走幅跳における鉛直速度獲得のための準備動作

    垣花渉, 鈴木秀次

    ヒューマンサイエンスリサーチ   9   275 - 284  2000年

  • 厚底靴の魅力とその危険性

    鈴木秀次

    体育科教育,大修館書店   2000 ( 4 ) 57 - 59  2000年

  • ソフトボールのウインドミル投法におけるボール速度を増大させる要因

    一之瀬貴, 鈴木秀次

    ヒューマンサイエンスリサーチ   9   261 - 274  2000年

    CiNii

  • ふれあいサイエンス・レポート 「速く走るための動きを科学的に解析してみませんか」

    鈴木秀次

    コーチング・クリニック,ベースボール・マガジン社   2000 ( 1 ) 49 - 52  2000年

  • Strength training improves the steadiness of slow lengthening contractions performed by old adults

    Laidlaw, DH, Kornatz KW, Keen, DA, Suzuki, S, Enoka, RM

    J. of Appl. Physiol   87 ( 5 ) 1789 - 1795  1999年

  • Strength training improves the steadiness of slow lengthening contractions performed by old adults

    Laidlaw, DH, Kornatz KW, Keen, DA, Suzuki, S, Enoka, RM

    J. of Appl. Physiol   87 ( 5 ) 1789 - 1795  1999年

  • Successive muscle contractions decrease recruitment force thresholds in single motor units(jointly worked)

    Suzuki, S, Hayami, A, Suzuki, M, Watanabe, S, Hutton, R.S

    Waseda Studies in Human Sciences   6 ( 1 ) 1 - 9  1993年

  • Successive muscle contractions decrease recruitment force thresholds in single motor units(jointly worked)

    Suzuki, S, Hayami, A, Suzuki, M, Watanabe, S, Hutton, R.S

    Waseda Studies in Human Sciences   6 ( 1 ) 1 - 9  1993年

  • Reductions in recruitment force thresholds in human single motor units by successive voluntary contractions(jointly worked)

    Suzuki, S, Hayami, A, Suzuki, M, Watanabe, S, Hutton, R.S

    Exp. Brain Res.   82   227 - 230  1990年

  • Reductions in recruitment force thresholds in human single motor units by successive voluntary contractions(jointly worked)

    Suzuki, S, Hayami, A, Suzuki, M, Watanabe, S, Hutton, R.S

    Exp. Brain Res.   82   227 - 230  1990年

  • POST-CONTRACTION ERRORS IN HUMAN FORCE PRODUCTION ARE REDUCED BY MUSCLE STRETCH

    RS HUTTON, K KAIYA, S SUZUKI, S WATANABE

    JOURNAL OF PHYSIOLOGY-LONDON   393   247 - 259  1987年12月

  • POST-CONTRACTION ERRORS IN HUMAN FORCE PRODUCTION ARE REDUCED BY MUSCLE STRETCH

    RS HUTTON, K KAIYA, S SUZUKI, S WATANABE

    JOURNAL OF PHYSIOLOGY-LONDON   393   247 - 259  1987年12月

  • Activation history and constant errors in human force production(jointly worked)

    Hutton, R.S, Enoka, R.M, Suzuki, S

    Brain Res.   307   344 - 346  1984年

  • Activation history and constant errors in human force production(jointly worked)

    Hutton, R.S, Enoka, R.M, Suzuki, S

    Brain Res.   307   344 - 346  1984年

  • AXON COLLATERALS TO THE EXTRA-OCULAR MOTONEURON POOLS OF INHIBITORY VESTIBULOOCULAR NEURONS ACTIVATED FROM THE ANTERIOR, POSTERIOR AND HORIZONTAL SEMICIRCULAR CANALS IN THE CAT

    Y UCHINO, S SUZUKI

    NEUROSCIENCE LETTERS   37 ( 2 ) 129 - 135  1983年

  • AXON COLLATERALS TO THE EXTRA-OCULAR MOTONEURON POOLS OF INHIBITORY VESTIBULOOCULAR NEURONS ACTIVATED FROM THE ANTERIOR, POSTERIOR AND HORIZONTAL SEMICIRCULAR CANALS IN THE CAT

    Y UCHINO, S SUZUKI

    NEUROSCIENCE LETTERS   37 ( 2 ) 129 - 135  1983年

  • EMG activity and Kinematics of human cycling movement at different constant velocities(jointly worked)

    Suzuki, S, Watanabe, S, Homma, S

    Brain Res.   240   245 - 258  1982年

  • Branching pattern and properties of vertical-and horizontal-related excitatory vestibuloocular neurons in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S

    J. Neurophysiology   48   891 - 903  1982年

  • EMG activity and Kinematics of human cycling movement at different constant velocities(jointly worked)

    Suzuki, S, Watanabe, S, Homma, S

    Brain Res.   240   245 - 258  1982年

  • Branching pattern and properties of vertical-and horizontal-related excitatory vestibuloocular neurons in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S

    J. Neurophysiology   48   891 - 903  1982年

  • Properties of secondary vestibular neurons fired by stimulation of ampullary nerve of the vertical, anterior or posterior semicircular canals in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S, Watanabe, S

    Brain Res.   223   273 - 286  1981年

  • Properties of secondary vestibular neurons fired by stimulation of ampullary nerve of the vertical, anterior or posterior semicircular canals in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S, Watanabe, S

    Brain Res.   223   273 - 286  1981年

  • VERTICAL SEMICIRCULAR CANAL INPUTS TO CAT EXTRA-OCULAR MOTO-NEURONS

    Y UCHINO, S SUZUKI, S WATANABE

    EXPERIMENTAL BRAIN RESEARCH   41 ( 1 ) 45 - 53  1980年

  • Axonal branching in the trochlear and ocuromotor nuclei of single vestibular neurons activates from the posterior semicircular canal nerve in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S, Watanabe, S

    Neurosci. Letters   18   283 - 288  1980年

  • VERTICAL SEMICIRCULAR CANAL INPUTS TO CAT EXTRA-OCULAR MOTO-NEURONS

    Y UCHINO, S SUZUKI, S WATANABE

    EXPERIMENTAL BRAIN RESEARCH   41 ( 1 ) 45 - 53  1980年

  • Axonal branching in the trochlear and ocuromotor nuclei of single vestibular neurons activates from the posterior semicircular canal nerve in the cat(jointly worked)

    Uchino, Y, Hirai, N, Suzuki, S, Watanabe, S

    Neurosci. Letters   18   283 - 288  1980年

  • Synaptic linkage between horizontal canal nerve and bilateral medical rectus motoneurons in the cat(jointly worked)

    Integral Control Functions of the Brain   (]G0002[)/,194-196  1979年

  • Postcontraction discharge of motor neurons in spinal animals(jointly worked)

    Hutton, R.S, Suzuki, S

    Exp. Neurol.   64   567 - 578  1979年

  • Horizontal canal input to cat extraocular motoneurons

    Uchino, Y, Suzuki, S, Miyazawa, T, Watanabe, S

    Brain Res.   177   231 - 240  1979年

  • Synaptic linkage between horizontal canal nerve and bilateral medical rectus motoneurons in the cat(jointly worked)

    Integral Control Functions of the Brain   (]G0002[)/,194-196  1979年

  • Postcontraction discharge of motor neurons in spinal animals(jointly worked)

    Hutton, R.S, Suzuki, S

    Exp. Neurol.   64   567 - 578  1979年

  • Horizontal canal input to cat extraocular motoneurons

    Uchino, Y, Suzuki, S, Miyazawa, T, Watanabe, S

    Brain Res.   177   231 - 240  1979年

  • Postcontractile motoneuronal discharge produced by muscle afferent activation

    Suzuki, S, Hutton, R.S

    Med. Sci. in Sports   8   258 - 264  1976年

  • Postcontractile motoneuronal discharge produced by muscle afferent activation

    Suzuki, S, Hutton, R.S

    Med. Sci. in Sports   8   258 - 264  1976年

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   in press

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   in press

  • A unique form of light-load training improves steadiness and performance on some functional tasks in older adults.

    Kobayashi K, Koyama Y, Enoka RM, Suzuki S

    Scandinavian Journal of Medicine and Science in Sports   in press

    DOI

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities.

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   in press

  • Interaction between thorax, lumbar, and pelvis movements in the transverse plane 4 during gait at three velocities.

    Yang YT, Yoshida Y, Hortobágyi T, Suzuki S

    Journal of Applied Biomechanics   in press

▼全件表示

受賞

  • 国際バイオメカニクス学会

    2011年  

  • 2011 International Society of Biomechanics (Taiwan)

    2011年  

共同研究・競争的資金等の研究課題

  • 太極拳の動作特性

    研究期間:

    2010年
    -
     
     

  • Motor Control and Biomechanics of Tai Chi Chuan

    研究期間:

    2010年
    -
     
     

  • 正しい歩行姿勢を保ちやすいビモロシューズのバイオメカニクス的手法による効果検証

    受託研究

    研究期間:

    2009年
    -
     
     

  • 初動負荷トレーニングの動作特性

    研究期間:

    2003年
    -
     
     

  • Neuromechanics of begining movement load training

    研究期間:

    2003年
    -
     
     

  • 身体運動時の運動制御とバイオメカニクス

  • ストレッチングの効果

  • Neuromechanics of human movement

  • Effect of stretching

▼全件表示

講演・口頭発表等

  • 下肢筋力トレーニングは高齢者の歩行特性を変化させる

    第69回日本体力医学会大会  

    発表年月: 2014年

  • 慢性期非特異的腰痛者3症例に対する徒手理学療法と理学的所見の考察

    第49回日本理学療法学術大会  

    発表年月: 2014年

  • ISOGAI DYNAMIC THERAPY MODIFIES HEALTHY YOUNG ADULT’S SPINAL LORDOSIS ANGLE IN STANDING

    The 20th Congress of the International Society of Electrophysiology and Kinesiology, Rome – ITALY  

    発表年月: 2014年

  • Relationship between lumbar lordosis angle and physical function in community-dwelling elderly males.

    59th Annual Meeting of the American College of Sports Medicine and 3rd World Congress on Exercise is Medicine  

    発表年月: 2012年

  • 陳式太極拳における金剛搗碓動作の運動制御とバイオメカニクス

    第12回日本電気生理運動学会  

    発表年月: 2011年

  • INFLUENCE OF FOREARM ORIENTATION ON MODULATION OF ELECTROMYOGRAPHIC ACTIVITY OF SHOULDER MUSCLES DURING ELBOW FLEXION TASKS IN HEALTHY ADULTS

    International Society of Biomechanics  

    発表年月: 2011年

  • BEGINNING MOVEMENT LOAD TRAINING IMPROVES STEADINESS OF OLDER ADULTS DURING SUBMAXIMAL ISOMETRIC CONTRACTIONS

    The XVIII Congress of the International Society of Electrophysiology and Kinesiology  

    発表年月: 2010年

  • Relationship between Spinal Sagittal Alignment and Physical Function of Community-dwelling Elderly Men

    57th AMERICAN COLLEGE OF SPORTS MEDICINE  

    発表年月: 2010年

  • Coordination of thoracic-lumbar-pelvic rotation during walking at different speeds

    The British Association of Sport and Exercise Sciences Annual Conference  

    発表年月: 2010年

  • 速度を変えて歩いたときの肩と骨盤の回旋と腰椎軸回転の関係

    文部科学省学術フロンティア研究プロジェクト「ライフステージに応じた健康増進と多様性保持」第3回研究発表会  

    発表年月: 2009年

  • 初動負荷トレーニングが高齢者の運動機能に与える影響

    文部科学省学術フロンティア研究プロジェクト「ライフステージに応じた健康増進と多様性保持」第3回研究発表会  

    発表年月: 2009年

  • 水平面から見た歩行時における骨盤と脊柱の協調性

    第64回日本体力医学会大会  

    発表年月: 2009年

  • 片側性筋収縮様式の違いが対側同名筋の皮質脊髄路興奮性に及ぼす影響

    第11回日本電気生理運動学会大会  

    発表年月: 2009年

  • Influence of the ipsilateral eccentric contraction training on force fluctuation in the untrained contralateral limb

    American College of Sports Medicine 56th Annual Meeting, Seattle  

    発表年月: 2009年

  • Axial rotation of lumbar spine during treadmill walking at three constant velocities

    American College of Sports Medicine 56th Annual Meeting, Seattle  

    発表年月: 2009年

  • Changes of joint torque during Tai Chi gait at different heights of center of body mass

    4th Asia-Pacific Congress on Sports Technology, Hawaii  

    発表年月: 2009年

  • ピアノ経験の有無による打鍵動作時の筋活動

    第10回日本電気生理運動学会  

    発表年月: 2007年

  • Nordic hamstring動作における筋電図およびキネマティクスの検討.

    第62回日本体力医学会大会  

    発表年月: 2007年

  • 長期の水中トレーニングによる伸張反射応答の特異的適応

    第62回日本体力医学会大会  

    発表年月: 2007年

  • 初動負荷トレーニング理論と運動機能改善第2報

    文部科学省学術フロンティア研究プロジェクト「ライフステージに応じた健康増進と多様性保持」第2回研究発表会  

    発表年月: 2007年

  • 初動負荷トレーニング理論と運動機能改善第3報

    文部科学省学術フロンティア研究プロジェクト「ライフステージに応じた健康増進と多様性保持」第2回研究発表会  

    発表年月: 2007年

  • 初動負荷トレーニング理論と運動機能改善

    文部科学省学術フロンティア研究プロジェクト「ライフステージに応じた健康増進と多様性保持」第1回研究発表会  

    発表年月: 2006年

▼全件表示

学内研究費(特定課題)

  • 気功における呼吸リズムの重要性

    2016年  

     概要を見る

    今回は、気功(八脈交会功)経験歴20年以上の女性2名・男性1名(年齢62.3±2.7歳・気功歴22.3±2.7年)、気功経験歴1年以下の女性3名(年齢57±16歳・気功歴0.6±0.4年)に協力頂き、動作中の呼吸とキネマティクスを調べた。その結果、この八脈交会功の継続的な実施は既存の心身症状を改善し、人々の健康寿命の延伸を図る運動として有効であることが示唆された。  

  • 気功の習慣化による心身健康状態の調査研究

    2015年  

     概要を見る

    本年度は、気功が心身の健康に及ぼす実感的な効果を定量化するため、導引養生功日本総本部第15回全国交流大会参加者1200名を対象にアンケート調査した。結果、抽出された代表的な身体症状の内、「身体の疲れ・だるさ (61%) 」,「冷え性 (55%) 」,および「体調を崩しやすい (53%) 」について改善を感じていると認められた。精神症状では、「疲れやすい (52%) について改善を感じていると認められた。また、身体症状については、性別を問わず60歳未満の方が気功による改善効果を感じていた。精神症状では,年代を問わず女性の方が改善効果を実感した。以上、気功 (導引養生功) によって、身体の疲れが改善され、疲れにくくなる効果があることが明らかになった。

  • 体幹姿勢と歩行動作の特性の関係に関するニューロメカニクス的研究

    2014年  

     概要を見る

     本研究は,若年者の体幹姿勢が歩行中の下肢関節運動に及ぼす影響を明らかにすることを目的とした.被験者は,健常な成人男性3名(20~21歳)とした.実験試技として,1) 通常姿勢,2) やや背中を曲げる,3) 深く背中を曲げる姿勢での歩行とした.歩行速度は通常速度および最大速度とした.試技中の身体位置座標を三次元動作分析装置で取得し,股関節,膝関節,および足関節の運動学的データを算出した. その結果,体幹姿勢変化によって,通常速度歩行の踵接地時点において高齢者と類似した歩行キネマティクスが生成されることが明らかになった.

  • 加齢に伴うストレッチング効果の違いを神経生理学から探る

    2013年  

     概要を見る

    筋の長さ変化を検出する筋紡錘は加齢によって形態と機能が変化する (Kim et al., 2007).したがって,関節可動域向上や神経筋興奮性低下を目的に行われるストレッチングの効果は,若年者と高齢者で異なる可能性が考えられるが,これまでこの点について検討した研究はない.そこで本研究は,H反射法を用いて非侵襲的にストレッチング後の若年者と高齢者の脊髄運動ニューロンプールの興奮性を評価した. 被験者は若年者(男女各5名,19~22歳)と高齢者7名(男性3名,女性4名,65~79歳)とした.被験者に安静座位を取らせた.膝窩部から後脛骨神経に経皮的電気刺激 (~60V, 1 msec) を与えてヒラメ筋のH反射を誘発し,双極誘導法によって筋電図活動を記録した.テスト刺激強度はH反射が最大M波の20~25%としたが,このサイズのH反射が誘発できない被験者については最大H反射振幅値未満となる刺激強度を用いた.また,テストサイズにおいて小さなM波を伴わない被験者は,最大M波の5%程度のサイズを伴うH反射を別途誘発し記録した.被験者に安静状態を保たせたまま,実験者が被験者の足関節を手動で120°から徐々に背屈しヒラメ筋をストレッチングした.背屈範囲は被験者が痛みを感じない最大範囲とし,角度計を用いて毎回の背屈範囲が一定になるように配慮した.ストレッチング時間は最大背屈位での保持時間0秒,10秒,30秒および60秒とし,基準位置に足関節を戻したのち10分間H反射を記録した.ストレッチング時間は被験者毎にランダム順とした. 保持時間0秒の場合,両群においてH反射振幅は変化しなかった.若年者では保持時間が10秒以上になるとストレッチング後1分間はH反射振幅が20~30%程度低下するが,低下量においてストレッチング時間の影響は観られず,2分後には基準程度に回復していた.高齢者群では,ストレッチング後にH反射が有意に低下するには60秒間必要であり,基準レベルに回復するまでは3分間必要であった. これらのことから,神経筋興奮性低下を目的としたストレッチング効果を高齢者に与える場合は,ストレッチング時間を若年者よりも長くする必要があると考えられた.

  • 太極拳動作の解析およびその運動メカニズムの大脳生理学的解明

    2012年  

     概要を見る

    太極拳は1644年前後に中国で生まれた拳法と呼吸法を統合した格闘技として編み出された(李天驥,1992)。 その熟練者は身体バランスや筋力の維持・向上のみでなく、高次認知機能においても優れていることが近年明らかになってきた。身体機能と認知機能の両方に効果があることは、従来のリハビリテーション法やスポーツとは異なる太極拳の大きな特徴であり、今後、高齢者や認知症患者の機能回復や運動機能維持・向上への応用が期待できる。しかし、太極拳の動作そのものに関しては経験的な表現が多く、運動制御とバイオメカニクスの見地から詳細に解明した研究は殆どない。よって、本研究は太極拳、特に震脚が含まれる伝統陳式太極拳の動作を検証すること。また太極拳熟練者の神経系の調節機構、特に認知機能への効果についても脳波解析から検討した。太極拳動作は金剛搗碓における震脚動作、すなわちヒトが立った状態から左足に体重を移動し、反対側の右脚を持ち上げ、その姿勢から一気に右脚を床面に向かって伸展した時の地面反力を調べた。被験者は健常男性15名とし、8名が陳式太極拳熟練者(1名の達人を含む)、残り7名が初心者であった。結果、右脚震脚時の最大地面反力は熟練者群が初心者群と比べて有意に大であった。特に達人は10.7 kNで、自体重の15.5倍を記録した。軸足(左)地面反力における圧力中心の移動距離は、熟練者群が有意に短かった。キネマティクスでは、軸(左)脚に注目すると初心者は右脚の動きに同調するかのように膝が幾分伸展し、身体重心が鉛直方向に熟練者よりも有意に上昇した。右脚の最上段から床面衝撃に至るまでに注目すると、その間の各セグメントの重心移動時間は初心者群で有意に長かった。さらに、初心者群では接地後も動きが収まらず、身体重心の沈み込みが有意に大であった。ところが、熟練者群では右足接地後の身体重心の沈み込みの距離、胴体の鉛直加速度が両方とも有意に小であった。興味ある動きは熟練者、特に達人は右足接地までの間に骨盤の多角的な回旋運動が、右膝伸展の前に見られた。筋活動は最初に左外側広筋、次に左大腿直筋、左脊柱起立筋、そして右脊柱起立筋、左外側広筋、左大腿直筋の順に、右足接地前に現れた。このような筋活動に沿った運動エネルギーの流れが、短時間に円滑に左下肢から右下肢へと移ったことが明らかとなり、達人が体重の15倍もの衝撃力を生み出した理由が垣間見えた。 次に、なぜ太極拳達人が人並み外れた技を発揮できるのか、長年の太極拳修練者の脳波を太極拳未実践者と比較、検討した。被験者は太極拳未経験の健常成人男性6名と、太極拳を実践している健常成人男性3名(太極拳経験年数:22.3±10.0年)であった。結果、太極拳を長期に渡って実践することで、特異な刺激に対する応答性の向上、および反応・対処すべき事象に対する記憶判断処理の向上が示唆される結果が得られた。

  • 太極拳動作の解析およびその運動メカニズムの大脳生理学的解明

    2011年   矢内 利政

     概要を見る

    太極拳は中国を起源とする武術の型を基礎とし、それに気功、軽絡学、陰陽二元説などの中国古来の理論を取り入れた健身養生術であり、意識と気(呼吸)と動作が一体となり、緩やかな動作(テンシケイ)が主となっている。その内、特に陳式太極拳ではハッケイ(突き)や震脚(シンキャク)と呼ばれる瞬時に完結する激しい動作が含まれる。熟練者では、一度動きが始まると止まるところがなく神経・骨格筋系や内臓の組織が一体となり同調して活動する。また、呼吸を整え身体をゆるめた状態で指、手、四肢、体幹を意識的に集中する動作が特徴であることから大脳認知機能への有用な効果が期待される。これらのことから太極拳を行うことによって肉体的にも精神的にも健康になる。太極拳の効用に関する研究は多数ある。しかし、太極拳の動作そのものに関しては経験的な表現が多く、運動制御とバイオメカニクスの見地から科学的に解明した研究は殆どない。よって、本研究課題として「太極拳、特にハッケイや震脚が含まれる伝統陳式太極拳の動作を科学的に検証すること」とした。陳式太極拳の基本動作形態は合計75の形(金剛搗碓、攬紮衣、六封四閉、単鞭、白鶴亮翅、斜行、掩手肱挙、雲手、巻肱等)がある。これらの演技を最初から終わりまで続けると約20分掛る。昨年度の研究では、熟練者が金剛搗碓の一連の動きを行なったときの身体重心変動を未熟練者と比較・検討した。結果、熟練者は一端動きが始まると腰を落とした状態の姿勢から、重心位置を左右・前後へ円滑に移動し、特に片脚立ちから対側脚への重心移動を行なったときにも片脚のみでバランスを保ちつつ重心を下げながら対側脚に円滑な体重移動を行なう動態をEMG活動と併せて示した。よって本年度は、金剛搗碓の終了時の震脚動作に限定して解析した。被験者は陳式太極拳の熟練者5名(38.8 ± 4.5 yr, 1.69 ± 0.07 m, 69.9 ± 9.9 kg)と初心者4名(40.0 ± 2.2 yrs, 1.69 ± 0.04 m, 68.8 ± 7.2 kg)であった。熟練者の内、1名は中国全国武術選手権大会太極拳部門準優勝者(達人)であった。試技中の動作は3次元動作解析システム(Motion Analysis社製)を 使用し、全身から計34箇所の位置データを記録し、3次元解析した。筋電計はWEB-5500(日本光電社製)を使用し、左右の脊柱起立筋、大腿直筋、外側広筋、大腿二頭筋、前脛骨筋、内・外側腓腹筋の計14ヶ所をテレメータから記録、解析した。地面反力は、キスラー社製の計測装置を用いて2 kHzで測定した。キネマティクスは得られた位置データから上肢、下肢の各関節角度、角速度、角加速度、頭頂、つま先の変位、速度、加速度、身体重心変位、速度、加速度を算出した。結果、熟練者は初心者に比べ、地面反力(鉛直方向成分:7764 ± 624 N vs. 4551 ± 518 N; mean ± SD , p < 0.05)、片脚つま先の床面に到達するまでの最大加速度(31.6 ± 3.7 m/s2 vs. 22.7 ± 5.3 m/s2 , p < 0.05)が顕著に大であった。特に達人においては10,719 Nと自体重の15倍を超える力が発揮されていた。このときの達人は、左軸脚外側広筋から大腿直筋、脊柱起立筋、そして反対側の脊柱起立筋、外側広筋、大腿直筋へと時空間的な加重によって爆発的な加速度を産み出し、力発揮の源となったと解釈でき、達人の技の一端が科学的に裏付けられた(研究代表者 成果1)。その他、太極拳動作の特徴として脳の興奮性と呼吸様式が挙げられることから、脳波計測におけるアーチファクトの問題(研究協力者 成果2)、及び呼吸様式の違いを力学的に検討した(連携研究者 成果3)。

  • 走運動技術獲得のためにマルチメディアを活用した教育システムの研究開発

    2002年   西村 昭治

     概要を見る

    本研究は、体育・スポーツの場における走力向上に役立つ写真・動画等を中心とした教材をマルチメディアデータベース化することと、それらをインターネットを介して公開するシステムを構築することであった。我々の研究は、走運動という“動き”を主体とするコンテンツをマルチメディア技術により“理論”と統合化して公開するところがこのシステムの特徴である。 2001年度には、子どもゆめ基金(独立行政法人国立オリンピック記念青少年総合センター)の助成金の交付も受けて「速く走るための動きを科学的に解析してみませんか」を実施し、そこでコンテンツ開発、特に指導法も含めたデータベースを開発し、教材として提供した(研究成果参照)。学校教育において科学的な指導を行う必要性を強く認識し、特に身体運動の基礎となる走運動(ランニング)について、その動き(動画・静止画と解析データ)、地面反力(解析データ)、筋活動(筋活動電位)を示し、ランニングという身体運動が科学的に見てどのような裏付けのもとに成り立っているかの学習素材コンテンツデータベースを開発した(研究成果参照、(http://www.kine.human.waseda.ac.jp/index-j.htm) 2002年度は、本学人間科学部が2003年度から開設の通信教育課程のなかで使用する教材「体育実技II」を制作し、オンデマンド授業を可能とした。学生がインターネット(Waseda-net)のブロードバンド接続によって、自宅に居ながら、いつでも好きな時間に、このオンデマンド型の授業に参加することは画期的な企画であった。2003年度の春学期で提供するデジタルコンテンツの内容は、より健康になるためのランニングおよびストレッチングについての意義と理論、さらに実技をデータ、映像、写真を交えてパワーポイントで解説した(研究成果参照)。

  • 自転車駆動中のペダルに掛かる力の作用点の測定システムの開発

    1997年  

     概要を見る

    今回我々は、3軸方向の踏力と左右前後に移動する力の作用点(Center of Pressure: C.O.P.)の測定を可能とするペダル踏力測定装置を新しく設計・製作した。フォースペダルは本体をアルミで、軸は鋼材を使用した。表面硬化のためとペダル軸硬化のため、それぞれアルマイト処理と熱処理を施した。センサーには、水晶クオーツを4個取り付けた。出力はX・Y軸成分を合成した後、8軸成分に変換し、接続ケーブルで8chチャージアンプに通した後、パソコンにデータを取り込んだ。フォースペダルから得られるデータは、ペダル踏面に対する鉛直方向成分(Fz)、水平前後方向成分(Fy)、水平左右方向成分(Fx)の力、そして C.O.P.とトルクTz(自由モーメント)であった。 本システムを用いて、2名の被験者に回転数の異なる一定仕事率(125 w)のペダリング運動を行わせ C.O.P.を定量的に測定したところ、すべての条件において踏み込み局面のC.O.P.は内側から外側に移動し、その移動距離は2 cm程度であった。踏み込み局面におけるC.O.P.のX軸座標と膝傾斜角度の関係をみたところ、60 rpm(2.1 kp)、38 rpm(3.3 kp)の条件下では、C.O.P.の外側への移動と膝傾斜角度の外側への傾斜、つまり膝の外反を示す数値の増減が同じ傾向にあることがわかった。一方、低回転・高負荷条件下(25 rpm・5.0 kp)では同じ傾向がみられず、この原因が踏み込み局面での足関節の圧迫によっておこる足部の回内に起因することが示唆された。 以上、今回作製の装置で、正確なC.O.P.と、3軸方向の合成によって描くペダル踏力のベクトルとを対応させながら、さらにペダリング時のキネマティックスを同時に調べることによって自転車駆動中における下肢の機能についてこれまで以上に詳細に解明することが可能となった。研究成果の発表発表年月:1997年6月、早稲田大学大学院人間科学研究科、ヒューマンサイエンスリサーチ論文題目:自転車ペダリング時の踏力作用点と脚キネマティックスの関係Vol.6、1997(131-138)

  • 左右脚の蹴りと振り出しを強化する筋力トレーニング

    1996年  

     概要を見る

     本研究は、被験者が筋力トレーニング機器を使って短距離走の模擬動作を行った時の動作のメカニズムについて考察した。被験者は左下肢を充分に伸展させたまま右下肢を屈曲-伸展させる動作を行った。動作は、右下肢の股関節屈曲伸展動作に対する負荷強度(L:40-45回の反復が可能な重量、H:10-15回の反復が可能な重量)、動作速度(F:1 Hz, S:0.17 Hz)、および左下肢の接地位置(中央、20cm 前方、20cm 後方)を変えて行った。EMG活動は、左腓腹筋、左ヒラメ筋、および右大腿直筋から導出した.股関節角度は、ゴニオメータを使って記録した。左下肢の床反力は、鉛直方向(Fz)、水平前後方向(Fy)、水平左右方向(Fx)の力、および力の作用点を計測した。一般的に、右股関節の屈曲-伸展時において右大腿直筋と左腓腹筋のEMG活動は共同活動が相動的に起こり、位相の変わり目はともに活動が弱まった。この間、左ヒラメ筋は、持続的に弱く活動した。軽い負荷強度で速く動作を行った時のFyは、右股関節屈曲開始時では推進方向成分を示したが、屈曲から伸展へ移る時にブレーキ方向成分へと変化した。Fzは、抜重により屈曲から伸展へと移る時に最小値を示し、全体として3相性の波形を示した。軽い負荷強度でゆっくり動作を行った時のFyは、推進方向成分のみとなり、Fzの大きさの変化は少なかった。重い負荷強度で速く動作を行った時のEMG活動は、左腓腹筋と左ヒラメ筋で増大が見られた。Fyは動作中全ての位相で推進方向成分のみとなった。Fzは屈曲-伸展の位相の変わり目での抜重による減少が比較的少なくなった。接地位置を変えたことによる床反力には基本的な違いが見られなかった。以上のことから、トレーニング機器を使って短距離走の模擬動作を行う時には、負荷強度や動作速度の設定に注意しなければならないことが示唆された。

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海外研究活動

  • 中高年者の健康維持増進のための合理的な体操の開発とその理論付け

    2010年04月
    -
    2011年03月

    アメリカ   コロラド大学

 

委員歴

  • 1985年
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    日本生理学会  評議員

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    日本電気生理運動学会  評議員

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    日本体力医学会  評議員