Muscle fatigue-induced enhancement of corticomuscular coherence following sustained submaximal isometric contraction of the tibialis anterior muscle

• DOI: 10.1152/japplphysiol.01194.2010
• Publication Date: 2011-03-11T03:42:03Z
• Authors: Junichi Ushiyama; Masanori Katsu; Yoshihisa Masakado; Akio Kimura; Meigen Liu; Junichi Ushiba
• Keywords: Muscle Fatigue; Tibialis anterior muscle

Oscillatory activity of the sensorimotor cortex shows coherence with muscle within 15- to 35-Hz frequency band (β-band) during weak moderate sustained isometric contraction. We aimed examine acute changes in this corticomuscular coupling due fatigue and its effect on steadiness exerted force. quantified between electroencephalogram (EEG) recorded over rectified surface electromyogram (EMG) tibialis anterior as well coefficient variance dorsiflexion force (Force(CV)) sum auto-power spectral density function β-band (Force(β-PSD)) 30% maximal voluntary contraction (MVC) for 60 s before (prefatiguing task) after (postfatiguing induced by at 50% MVC until exhaustion seven healthy male subjects. The magnitude EEG-EMG increased postfatiguing task six peak stayed both pre- tasks. Interestingly, two subjects, who had no significant prefatiguing task, showed task. Additionally, Force(CV) Force(β-PSD) significantly fatigue. These data suggest that when develops, central nervous system enhances oscillatory muscular stronger coupled accomplishing lower performance levels.