The Effect of Antagonist Muscle Sensory Input on Force Regulation. PLoS One 2015;10(7):e0133561
Date
07/18/2015Pubmed ID
26186590Pubmed Central ID
PMC4506057DOI
10.1371/journal.pone.0133561Scopus ID
2-s2.0-84941348356 (requires institutional sign-in at Scopus site) 3 CitationsAbstract
The purpose of this study was to understand how stretch-related sensory feedback from an antagonist muscle affects agonist muscle output at different contraction levels in healthy adults. Ten young (25.3 ± 2.4 years), healthy subjects performed constant isometric knee flexion contractions (agonist) at 6 torque levels: 5%, 10%, 15%, 20%, 30%, and 40% of their maximal voluntary contraction. For half of the trials, subjects received patellar tendon taps (antagonist sensory feedback) during the contraction. We compared error in targeted knee flexion torque and hamstring muscle activity, with and without patellar tendon tapping, across the 6 torque levels. At lower torque levels (5%, 10%, and 15%), subjects produced greater knee torque error following tendon tapping compared with the same torque levels without tendon tapping. In contrast, we did not find any difference in torque output at higher target levels (20%, 30%, and 40%) between trials with and without tendon tapping. We also observed a load-dependent increase in the magnitude of agonist muscle activity after tendon taps, with no associated load-dependent increase in agonist and antagonist co-activation, or reflex inhibition from the antagonist tapping. The findings suggest that at relatively low muscle activity there is a deficiency in the ability to correct motor output after sensory disturbances, and cortical centers (versus sub-cortical) are likely involved.
Author List
Onushko T, Schmit BD, Hyngstrom AAuthors
Allison Hyngstrom PhD Associate Professor in the Physical Therapy department at Marquette UniversityBrian Schmit PhD Professor in the Biomedical Engineering department at Marquette University
MESH terms used to index this publication - Major topics in bold
AdultBiomechanical Phenomena
Electromyography
Feedback, Sensory
Humans
Knee
Male
Motor Activity
Muscle, Skeletal
Range of Motion, Articular
Sensation
Torque