HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Electromechanical delay revisited using very high frame rate ultrasound

Abstract : Electromechanical delay (EMD) represents the time lag between muscle activation and muscle force production and is used to assess muscle function in healthy and pathological subjects. There is no experimental methodology to quantify the actual contribution of each series elastic component structures that together contribute to the EMD. We designed the present study to determine, using very high frame rate ultrasound (4 kHz), the onset of muscle fascicles and tendon motion induced by electrical stimulation. Nine subjects underwent two bouts composed of five electrically evoked contractions with the echographic probe maintained over 1) the gastrocnemius medialis muscle belly (muscle trials) and 2) the myotendinous junction of the gastrocnemius medialis muscle (tendon trials). EMD was 11.63 +/- 1.51 and 11.67 +/- 1.27 ms for muscle trials and tendon trials, respectively. Significant difference (P < 0.001) was found between the onset of muscle fascicles motion (6.05 +/- 0.64 ms) and the onset of myotendinous junction motion (8.42 +/- 1.63 ms). The noninvasive methodology used in the present study enabled us to determine the relative contribution of the passive part of the series elastic component (47.5 +/- 6.0% of EMD) and each of the two main structures of this component (aponeurosis and tendon, representing 20.3 +/- 10.7% and 27.6 +/- 11.4% of EMD, respectively). The relative contributions of the synaptic transmission, the excitation-contraction coupling, and the active part of the series elastic component could not be directly quantified with our results. However, they suggest a minor role of the active part of the series elastic component that needs to be confirmed by further experiments.
Document type :
Journal articles
Complete list of metadata

Contributor : Pascale Talour Connect in order to contact the contributor
Submitted on : Friday, January 15, 2010 - 11:39:58 AM
Last modification on : Wednesday, April 27, 2022 - 4:34:12 AM



Antoine Nordez, Thomas Gallot, Stefan Catheline, Arnaud Guével, Christophe Cornu, et al.. Electromechanical delay revisited using very high frame rate ultrasound. Journal of Applied Physiology, American Physiological Society, 2009, 106 (6), pp.1970-1975. ⟨10.1152/japplphysiol.00221.2009⟩. ⟨insu-00447530⟩



Record views