Muscle-Monitoring Textiles: Cutaneous Recording and Stimulation of Muscles Using Organic Electronic Textiles (Adv. Healthcare Mater. 16/2016)

Cutaneous Recording and Stimulation of Muscles Using Organic Electronic Textiles

International audience; Electronic textiles are an emerging field providing novel and non-intrusive solutions for healthcare. Conducting polymer-coated textiles enable a new generation of fully organic surface electrodes for electrophysiological evaluations. Textile electrodes are able to assess high quality muscular monitoring and to perform transcutaneous electrical stimulation.

Neuromuscular Fatigue Is Not Different between Constant and Variable Frequency Stimulation

International audience; This study compared fatigue development of the triceps surae induced by two electrical stimulation protocols composed of constant and variable frequency trains (CFTs, VFTs, 450 trains, 30 Hz, 167 ms ON, 500 ms OFF and 146 ms ON, 500 ms OFF respectively). For the VFTs protocol a doublet (100 Hz) was used at the beginning of each train. The intensity used evoked 30% of a maximal voluntary contraction (MVC) and was defined using CFTs. Neuromuscular tests were performed before and after each protocol. Changes in excitation-contraction coupling were assessed by analysing the M-wave [at rest (M-max) and during MVC (M-sup)] and associated peak twitch (Pt). H-reflex [at rest…

Spinal and supraspinal mechanisms affecting torque development at different joint angles

INTRODUCTION We examined the neural mechanisms responsible for plantar flexion torque changes at different joint positions. METHODS Nine subjects performed maximal voluntary contractions (MVC) at 6 ankle-knee angle combinations [3 ankle angles (dorsiflexion, anatomic position, plantar flexion) and 2 knee angles (flexion, full extension)]. Neural mechanisms were determined by V-wave, H-reflex (at rest and during MVC), and electromyography during MVC (RMS), normalized to the muscle compound action potential (V/Msup, Hmax/Mmax, Hsup Msup and RMS/Msup) and voluntary activation (VA), while muscle function was assessed by doublet amplitude. RESULTS MVC and doublet amplitude were significantly low…

Electrically induced torque decrease reflects more than muscle fatigue

The aim of the study was to compare the fatigue induced by different electrical stimulation (ES) protocols. The triceps surae muscle of 8 healthy subjects was fatigued with 4 protocols (30 Hz-500 μs, 30 Hz-1 ms, 100 Hz-1 ms, and 100 Hz-500 μs), composed of 60 trains (4 s on-6 s off), delivered at an intensity evoking 30% of maximal voluntary contraction (MVC). Fatigue was quantified by ES and MVC torque decreases. The amplitude of the twitch delivered at the intensity and pulse width used in each fatiguing protocol (twitch at Istim ) was analyzed. All parameters decreased significantly after all protocols. The ES torque decrease correlated positively with the twitch decrease elicited at Ist…