Increases of Quadriceps Inter-Muscular Cross-Correlation and Coherence during Exhausting Stepping Exercise

Sensors

Ya-Ju Chang³  Ching-Chieh Chou³  Hsiao-Lung Chan⁴  Miao-Ju Hsu¹  Ming-Yuh Yeh⁴  Chia-Ying Fang³  Yu-Fen Chuang³  Shun-Hwa Wei² 

[1] Department of Physical Therapy, College of Health Science, Kaohsiung Medical University, 100,Shih-Chuan 1st Road, Kaohsiung 80708, Taiwan; E-Mail:;Department of Physical Therapy and Assistive Technology, National Yang Ming University, 155, Sec.2, Linong Street, Taipei 112, Taiwan; E-Mail:;Department of Physical Therapy and Graduate Institute of Rehabilitation Science, Chang Gung University, 259, Wen-Hwa 1st Rd, Kweishan, Taoyuan 333, Taiwan; E-Mails:;Department of Electrical Engineering, Chang Gung University, 259, Wen-Hwa 1st Rd, Kweishan, Taoyuan 333, Taiwan; E-Mail:

关键词: intermuscular;    cross-correlation;    coherence;    muscle fatigue and stepping;   

DOI  :  10.3390/s121216353

来源: mdpi

【 摘 要 】

The aim of this study was to examine the change of the intermuscular cross-correlation and coherence of the rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL) during exhausting stepping exercise. Eleven healthy adults repeated the stepping exercise up to their individual endurance limits (RPE score reached 20), and the cross-correlation and coherence were assessed by surface electromyography (EMG) recordings. The coefficient and time lag of cross-correlation and the coherence areas in the alpha (8–12 Hz), beta (15–30 Hz), gamma (30–60 Hz) and high-gamma (60–150 Hz) bands among the three muscle pairs (RF-VM, RF-VL and VM-VL) were calculated. As muscle fatigue, RF-VM and VM-VL showed increases of coefficients and the shortening of time lags. RF-VM and RF-VL showed increases of beta-band coherence in the ascent and descent phases, respectively. The increased intermuscular cross-correlation and beta-band coherence may be a compensatory strategy for maintaining the coordination of knee synergistic muscles during fatigue due to the fatigue-related disturbance of the corticospinal transmission. Therefore, the intermuscular cross-correlation and beta-band coherence may be a potential index for assessing muscle fatigue and monitoring the central control of motor function during dynamic fatiguing exercise.

【 授权许可】

CC BY   
© 2012 by the authors; licensee MDPI, Basel, Switzerland