Time–frequency analysis and estimation of muscle fiber conduction velocity from surface EMG signals during explosive dynamic contractions

Pain-induced changes in cervical muscle activation do not affect muscle fatigability during sustained isometric contraction

“…It may be argued that the change in initial MNF is a result of the lower EMG amplitude, and thus reduced muscle activation, during the painful condition. However, absolute values of the MNF are poorly correlated with muscle fiber membrane properties (e.g., muscle fiber conduction velocity) or motor unit recruitment (Falla et al, 2006;Farina et al, 2002;Farina et al, 2004b;Masuda et al, 1999;Merlo et al, 2005). Thus, changes in absolute values of MNF cannot be attributed to specific physiological mechanisms.…”

Muscle fluid shift does not alter EMG global variables during sustained isometric actions

“…Less is known about the effect of microgravity on muscular endurance characteristics. Changes in muscle fatigability can be assessed through their myoelectrical manifestations, i.e., by estimating electromyographic (EMG) spectral variables (mean power frequency, MNF) (Antonutto and Di Prampero, 2003;Merletti and Lo Conte, 1997) during isometric, constant force actions (although more sophisticated methods are needed for variable-force tasks (Merlo et al, 2005;Pozzo et al, 2006)). Hence, EMG techniques provide a tool for monitoring the effectiveness of in-flight countermeasures (Berg and Tesch, 1994).…”

Piper rhythm of the electromyograms of the abductor pollicis brevis muscle during isometric contractions

“…One has therefore to differentiate between some MUAP that occur in a stochastic order, those that occur in a rhythmic order and those that occur in a synchronized way e.g. during an explosive movement (Merlo et al, 2005).…”