Changes in the spatial distribution of RMS values with knee position.

<p>Median values and inter-quartile intervals are shown for the RMS amplitude (<i>a</i>), the <i>active channels</i> (<i>b</i>) and the barycentre coordinate (<i>c</i>). These variables were respectively normalised with respect to the maximal RMS value obtained at 100% MVC attempts performed during knee extended position, the total number of channels located over the MG superficial aponeurosis and the distance between the femoral condyle and the distal extremity of the superficial aponeurosis (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126888#pone.0126888.g001" target="_blank">Fig 1</a>). Asterisks denote statistical significance at <i>P</i><0.05.</p>