Abstract:
:Muscle fatigue often occurs over a long period of exercise, and it can increase the risk of muscle injury. Evaluating the state of muscle fatigue can avoid unnecessary overtraining and injury of the muscle. Ultrasound imaging can non-invasively visualize muscle tissue in real-time. Image entropy is commonly used to characterize the texture of an image. In this study, we evaluated changes in the ultrasound image entropy (USIE) during the fatigue process. Twelve volunteers performed static sustained contractions of biceps brachii at four different intensities (20%, 30%, 40%, and 50% of maximal voluntary contraction torque). The ultrasound images and surface electromyography (sEMG) signals were acquired during exercise to fatigue. We found that (1) the root-mean-square of the sEMG signal increased, the USIE decreased significantly with time during the sustained contractions; (2) the maximum endurance time (MET) and the decline percentage of USIE were significantly different (p < .05) among the four contraction intensities; (3) the decline slope of USIE of the same volunteer was basically the same at different contraction intensities. The USIE could be a new method for the evaluation of skeletal muscle fatigue state.
journal_name
Ultrason Imagingjournal_title
Ultrasonic imagingauthors
Li P,Yang X,Yin G,Guo Jdoi
10.1177/0161734620952683subject
Has Abstractpub_date
2020-11-01 00:00:00pages
235-244issue
6eissn
0161-7346issn
1096-0910journal_volume
42pub_type
杂志文章abstract::The liver has been hypothesized to have a unique arrangement of microvasculature that presents as an arrangement of quasiperiodic scatterers to an interrogating ultrasound pulse. The mean scatterer spacing (MSS) of these quasiperiodic scatterers has been proposed as a useful quantitative ultrasound biomarker for chara...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734613511232
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469401600202
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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abstract::Breast ultrasound (BUS) imaging has become a crucial modality, especially for providing a complementary view when other modalities (i.e., mammography) are not conclusive in the task of assessing lesions. The specificity in cancer detection using BUS imaging is low. These false-positive findings often lead to an increa...
journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460102300101
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734620902527
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/0161734615600167
更新日期:2016-07-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460502700205
更新日期:2005-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173469501700101
更新日期:1995-01-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460302500303
更新日期:2003-07-01 00:00:00
abstract::Previously reported data on the temperature dependence of propagation speed in tissues generally span only temperature ranges up to 60 degrees C. However, with the emerging use of thermal ablative therapies, information on variation in this parameter over higher temperature ranges is needed. Measurements of the ultras...
journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460202400404
更新日期:2002-10-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460602800203
更新日期:2006-04-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173468500700402
更新日期:1985-10-01 00:00:00
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
doi:10.1177/016173460803000301
更新日期:2008-07-01 00:00:00
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journal_title:Ultrasonic imaging
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doi:10.1177/016173460002200201
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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pub_type: 杂志文章,评审
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journal_title:Ultrasonic imaging
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
pub_type: 杂志文章
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journal_title:Ultrasonic imaging
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