title: Motor unit firing pattern of vastus lateralis muscle in type 2 diabetes mellitus patients.
abstract: BACKGROUND
  We investigated the motor unit (MU) firing pattern in type 2 diabetes mellitus (T2DM) patients by means of multichannel surface electromyography (SEMG).
  
  
  METHODS
  Eight T2DM patients and 8 age-matched, healthy men performed a ramp-up contraction to 20% of maximal voluntary contraction (MVC). They also performed a sustained contraction at 10% of MVC during isometric knee extension. Multichannel SEMG signals recorded from the vastus lateralis muscle were decomposed with the convolution kernel compensation technique to extract individual MU firing patterns.
  
  
  RESULTS
  During the ramp contraction, the extent of MU firing modulation was significantly attenuated in T2DM. Variability of MU firing rate was significantly higher in T2DM at later periods during the sustained contraction.
  
  
  CONCLUSIONS
  Our findings suggest that T2DM patients manifest characteristic MU activity patterns due possibly to some degree of neuromuscular impairment affecting the integrity of MU firing modulation.
authors: School of International Liberal Studies, Chukyo University, Yagotohonmachi, Showa-ku, Nagoya, 466-8666, Japan; Laboratory of Applied Physiology, Graduate School of Human and Environmental Studies, Kyoto University, Kyoto, Japan.
authors: Kohei
authors: K
authors: Watanabe
authors: Marco
authors: M
authors: Gazzoni
authors: Ales
authors: A
authors: Holobar
authors: Toshiaki
authors: T
authors: Miyamoto
authors: Kazuhito
authors: K
authors: Fukuda
authors: Roberto
authors: R
authors: Merletti
authors: Toshio
authors: T
authors: Moritani
mesh_terms: D000368:Aged; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D004576:Electromyography / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007717:Knee / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D052097:Quadriceps Muscle / Q000294:innervation / Q000503:physiopathology*; D011999:Recruitment, Neurophysiological / Q000502:physiology*
keywords: firing rate; knee extensors; multichannel surface electromyography; type 2 diabetes mellitus; vastus lateralis