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Updated: Aug 18, 2026

A Simple Non-invasive Method for Temporary Knockdown of Upper Limb Proprioception
Published on: March 3, 2018
Task-specific recruitment of motor units for vibration damping
James M Wakeling1, Anna-Maria Liphardt
1Structure and Motion Laboratory, The Royal Veterinary College, North Mymms, Herts AL9 7TA, UK. jwakeling@rvc.ac.uk
Abstract:
Vibrations occur within the soft tissues of the lower extremities due to the heel-strike impact during walking. Increases in muscle activity in the lower extremities result in increased damping to reduce this vibration. The myoelectric intensity spectra were compared using principal component analysis from the tibialis anterior and lateral gastrocnemius of 40 subjects walking with different shoe conditions. The soft insert condition resulted in a significant, simultaneous increase in muscle activity with a shift to higher myoelectric frequencies in the period 0-60 ms after heel-strike which is the period when the greater vibration damping occurred. These increases in myoelectric frequency match the spectral patterns which indicate increases in recruitment of faster motor units. It is concluded that fast motor units are recruited during the task of damping the soft-tissue resonance that occurs following heel-strike.
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