Muscle fiber velocity and electromyographic signs of fatigue in fibromyalgia
Muscle & Nerve, 05/04/2012
Klaver–Krol EG et al. – In the patients with Fibromyalgia (FM), the authors clearly showed functional abnormalities of the muscle membrane which lead to high conduction velocity and resistance to fatigue in electromyography.Methods
- Surface electromyography (SEMG) was performed on the biceps brachii muscle of 13 women with FM and 14 matched controls during prolonged dynamic exercises, unloaded and loaded up to 20% of maximum voluntary contraction.
- The sEMG parameters were: muscle fiber conduction velocity (CV), skewness of motor unit potential (peak) velocities, peak frequency (PF) (number of peaks per second) and average rectified voltage (ARV).
- There was significantly higher CV in the FM group.
- Although the FM group performed the tests equally well, their electromyographic fatigue was significantly less expressed compared with controls (in CV, PF and ARV).