What is "mechanomyogram"

n. The low-frequency mechanical signal observable from the surface of a muscle when the muscle is contracted.

The mechanomyogram (MMG) is the mechanical signal observable from the surface of a muscle when the muscle is contracted. At the onset of muscle contraction, gross changes in the muscle shape cause a large peak in the MMG. Subsequent vibrations are due to oscillations of the muscle fibres at the resonance frequency of the muscle. The mechanomyogram is also known as the phonomyogram, acoustic myogram, sound myogram or vibromyogram.