著者

Masatoshi Nakamura Tome Ikezoe Satoru Nishishita Hiroki Tanaka Jun Umehara Noriaki Ichihashi

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.8, no.3, pp.113-116, 2019-05-25 (Released:2019-05-18)

参考文献数

24

被引用文献数

9 15

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Static stretching (SS) is widely used to decrease and retain the passive stiffness of the muscle-tendon unit in clinical and athletic settings. It is important to consider the minimum SS duration required to decrease the passive stiffness of the hamstring, from the perspective of injury prevention of the hamstring muscle. The purpose of this study was to investigate the time course of the effect of static stretching (SS) on passive stiffness of the hamstring and to clarify the minimum SS duration required to decrease the passive stiffness. Fifteen healthy males participated in this study. Fifteen healthy and non-athlete male volunteers participated in this study. SS of 60-s session was performed for five sessions with a 30-s rest between sessions. Passive stiffness was measured prior to SS (PRE) and immediately after each SS session to determine the minimum SS duration required to decrease the passive stiffness. The passive stiffness was calculated as the slope of the torque-angle curve corresponding to 50% of the final angle (Nm/°). Passive stiffness after 180, 240, and 300 s of SS was significantly lower than that at PRE. Our results showed that SS for >180 s is recommended to decrease the passive stiffness of the hamstring muscle.

著者

Aoi MATSUMURA Hiroshige TATEUCHI Masatoshi NAKAMURA Noriaki ICHIHASHI

出版者

Japanese Society of Physical Therapy

雑誌

Physical Therapy Research (ISSN:21898448)

巻号頁・発行日

vol.26, no.2, pp.58-64, 2023 (Released:2023-08-20)

参考文献数

29

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Objective: Generally, low-intensity training is recommended as selective training of the infraspinatus muscle. This study aimed to investigate whether an 8-week intervention of low-intensity, slow-movement, external rotation exercise of the shoulder led to an increase in muscle strength with shoulder external rotation and cross-sectional area (CSA) infraspinatus muscle. Methods: Sixteen healthy male volunteers were randomly assigned to the low-intensity and slow-movement (LS) group (N = 8) or the normal-intensity and normal-speed (NN) group (N = 8). The LS and NN groups performed shoulder external rotation exercises with low intensity and slow movement, and normal intensity and normal speed, respectively. The exercise session consisted of three sets of 10 repetitions, which were performed three times per week for 8 weeks. We measured the CSA of the infraspinatus and muscle strength of the shoulder external rotation before and after the 8-week intervention. Results: A significant increase in infraspinatus CSA from baseline to 8 weeks was found in the LS group (7.3% of baseline) but not in the NN group. No significant differences were found in the muscle strength of shoulder external rotation. Conclusion: Our results suggest that low-intensity exercise of the infraspinatus is effective for muscle hypertrophy when performed with slow movement. This finding may help patients who should avoid excessive stress in the early phase of rehabilitation.

著者

Aoi MATSUMURA Hiroshige TATEUCHI Masatoshi NAKAMURA Noriaki ICHIHASHI

出版者

Japanese Society of Physical Therapy

雑誌

Physical Therapy Research (ISSN:21898448)

巻号頁・発行日

pp.E10227, (Released:2023-04-22)

参考文献数

29

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Objective: Generally, low-intensity training is recommended as selective training of the infraspinatus muscle. This study aimed to investigate whether an 8-week intervention of low-intensity, slow-movement, external rotation exercise of the shoulder led to an increase in muscle strength with shoulder external rotation and cross-sectional area (CSA) infraspinatus muscle. Methods: Sixteen healthy male volunteers were randomly assigned to the low-intensity and slow-movement (LS) group (N = 8) or the normal-intensity and normal-speed (NN) group (N = 8). The LS and NN groups performed shoulder external rotation exercises with low intensity and slow movement, and normal intensity and normal speed, respectively. The exercise session consisted of three sets of 10 repetitions, which were performed three times per week for 8 weeks. We measured the CSA of the infraspinatus and muscle strength of the shoulder external rotation before and after the 8-week intervention. Results: A significant increase in infraspinatus CSA from baseline to 8 weeks was found in the LS group (7.3% of baseline) but not in the NN group. No significant differences were found in the muscle strength of shoulder external rotation. Conclusion: Our results suggest that low-intensity exercise of the infraspinatus is effective for muscle hypertrophy when performed with slow movement. This finding may help patients who should avoid excessive stress in the early phase of rehabilitation.

著者

Noriaki Ichihashi Satoko Ibuki Masatoshi Nakamura

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

The Journal of Physical Fitness and Sports Medicine (ISSN:21868131)

巻号頁・発行日

vol.3, no.1, pp.1-10, 2014-03-25 (Released:2014-03-20)

参考文献数

76

被引用文献数

2 2

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The acute and chronic effects of static stretching (SS) on joint range of motion (ROM) and stiffness of muscle-tendon unit (MTU) and/or muscle was reviewed. Previous studies have provided evidence that SS is effective in increasing ROM, both immediately and chronically. Moreover, 75 seconds (75s) SS is sufficient for eliciting an immediate, acute effect. In contrast, the recent trend is to evaluate the effect of stretching not by measuring ROM, but by measuring stiffness in order to eliminate the effect of psychological factors. However, the findings of studies measuring stiffness are conflicting, with some results indicating a decrease in stiffness and others indicating no change in stiffness despite changes in joint ROM. Our study results support that stiffness decrease with SS, and that >2 min of SS is effective in eliciting the effect. The retention time taken to achieve the effect of SS is also under discussion, and the retention time may differ for ROM and muscle stiffness. Concerning the chronic effect of SS, many studies have indicated that a routine SS program decreases passive torque or MTU and muscle stiffness. However, the underlying mechanism for this decrease remains to be clarified.