Journal article
Motor unit recruitment strategies are altered during deep-tissue pain
The Journal of Neuroscience, Vol.29(35), pp.10820-10826
2009
PMCID: PMC6665526
PMID: 19726639
Abstract
Muscle pain is associated with decreased motor unit discharge rate during constant force contractions. As discharge rate is a determinant of force, other adaptations in strategy must explain force maintenance during pain. Our aim was to determine whether motor unit recruitment strategies are altered during pain to maintain force despite reduced discharge rate. Motor unit discharge behavior was recorded in two muscles, one with (quadriceps) and one without [flexor pollicis longus (FPL)] synergists. Motor units were recruited during matched low-force contractions with and without experimentally induced pain, and at higher force without pain. A total of 52 and 34 units were recorded in quadriceps and FPL, respectively, during low-force contractions with and without pain. Of these, 20 quadriceps and 9 FPL units were identified during both trials. The discharge rate of these units reduced during pain in both muscles [quadriceps: 8.7 (1.5) to 7.5 (1.3) Hz, p < 0.001; FPL: 11.9 (1.5) to 10.0 (1.7) Hz, p < 0.001]. All remaining units discharged only with or without pain, but not in both conditions. Only one-third of the additional units recruited during pain (quadriceps n = 7/19, FPL n = 3/15) were those expected given orderly recruitment of the motor unit pool as determined during higher-force contractions. We conclude that reduced motor unit discharge rate with pain is accompanied by changes in the population of units used to maintain force. The recruitment of new units is partly inconsistent with generalized inhibition of the motoneuron pool predicted by the "pain adaptation" theory, and provides the basis for a new mechanism of motor adaptation with pain.
Details
- Title
- Motor unit recruitment strategies are altered during deep-tissue pain
- Authors
- Kylie Tucker (Author) - University of QueenslandJane Butler (Author) - Prince of Wales Medical Research InstituteThomas Graven-Nielsen (Author) - Aalborg UniversityStephan Riek (Author) - University of QueenslandPaul Hodges (Author) - University of Queensland
- Publication details
- The Journal of Neuroscience, Vol.29(35), pp.10820-10826
- Publisher
- Society for Neuroscience
- DOI
- 10.1523/JNEUROSCI.5211-08.2009
- ISSN
- 1529-2401
- PMID
- 19726639; PMC6665526
- Organisation Unit
- University of the Sunshine Coast, Queensland; Graduate Research School
- Language
- English
- Record Identifier
- 99472602802621
- Output Type
- Journal article
Metrics
10 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- International collaboration
- Web Of Science research areas
- Neurosciences
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites