Assessment of muscle performance by dynamic ratio of MMG and EMG during dynamic exercise

Abstract

Mechanomyogram (MMG) measurement with body movements is difficult, quantitative muscle contraction using MMG and electromyogram (EMG) during dynamic exercise has not been evaluated. By using the MMG/EMG hybrid transducer system developed previously, it could evaluate muscle contraction with dynamic exercise. The present study aimed to evaluate muscle performance using this system during dynamic exercise. The MMG and EMG were measured for the vastus medialis of four subjects using recumbent bicycle. The ratio of MMG and EMG (dynamic MMG/EMG) showed decreasing tendency for all subjects as pedal load increased. Extent of reduction was divided into two patterns, that is, a gentle one and a sharp one. This results was suspected that dynamic MMG/EMG reflected exercise efficiency and individual reserve capacity of muscle strength against execise load. The dynamic MMG/EMG reflects muscle performance during dynamic exercise, and may be a new indicator to evaluate muscle function in recovery rehabilitation and sports training.