Evaluation of isokinetic muscle performance using a novel mechanomyogram sensor

Abstract

A pilot investigation was conducted on the measurement of muscle performance during voluntary exercise using a novel mechanomyogram muscle contraction sensor quantifying muscle tension - the MC-Sensor (TMG-BMC Ltd. Ljubljana, Slovenia). Surface electromyography (sEMG) and the torque output from an isokinetic dynamometer were used as reference for comparative assessment of the MC-sensor data. Five able-bodied subjects performed isokinetic knee extension at 90 deg· s-1 and 120 deg· s-1. Correlation coefficients (r) between the muscle tension data from MC-sensor, sEMG and Biodex were calculated using Microsoft Excel and a high correlation was observed with an average rvalue of 0.82 to 0.91 at 90 deg· s1, and 0.77 to 0.90 at 120 deg· s-1, respectively. A stronger association was observed between MC-sensor and Biodex, compared to MC-EMG and Biodex-EMG. This might be due to reported complications in achieving an accurate force-EMG ratio. However, further research is necessary to establish the reliability of the mechanomyogram sensors before muscle tension can be utilized as a proxy for muscle force during functional electrical stimulation(FES)-evoked exercise and/or functional movements.