Influence of passive muscle tension on electromechanical delay in humans

Lacourpaille, Lilian, Hug, Francois and Nordez, Antoine (2013) Influence of passive muscle tension on electromechanical delay in humans. PLoS ONE, 8 1: e53159.1-e53159.5. doi:10.1371/journal.pone.0053159

Author Lacourpaille, Lilian
Hug, Francois
Nordez, Antoine
Title Influence of passive muscle tension on electromechanical delay in humans
Journal name PLoS ONE   Check publisher's open access policy
ISSN 1932-6203
Publication date 2013-01-01
Year available 2013
Sub-type Article (original research)
DOI 10.1371/journal.pone.0053159
Open Access Status DOI
Volume 8
Issue 1
Start page e53159.1
End page e53159.5
Total pages 6
Place of publication San Francisco, CA United States
Publisher Public Library of Science
Language eng
Formatted abstract
Background: Electromechanical delay is the time lag between onsets of muscle activation and muscle force production and reflects both electro-chemical processes and mechanical processes. The aims of the present study were two-fold: to experimentally determine the slack length of each head of the biceps brachii using elastography and to determine the influence of the length of biceps brachii on electromechanical delay and its electro-chemical/mechanical processes using very high frame rate ultrasound.

First, 12 participants performed two passive stretches to evaluate the change in passive tension for each head of the biceps brachii. Then, they underwent two electrically evoked contractions from 120 to 20° of elbow flexion (0°: full extension), with the echographic probe maintained over the muscle belly and the myotendinous junction of biceps brachii. The slack length was found to occur at 95.5 ± 6.3° and 95.3 ± 8.2° of the elbow joint angle for the long and short heads of the biceps brachii, respectively. The electromechanical delay was significantly longer at 120° (16.9 ± 3.1 ms; p<0.001), 110° (15.0 ± 3.1 ms; p<0.001) and 100° (12.7 ± 2.5 ms; p = 0.01) of elbow joint angle compared to 90° (11.1 ± 1.7 ms). However, the delay between the onset of electrical stimulation and the onset of both muscle fascicles (3.9 ± 0.2 ms) and myotendinous junction (3.7 ± 0.3 ms) motion was not significantly affected by the joint angle (p>0.95).

Conclusion: In contrast to previous observations on gastrocnemius medialis, the onset of muscle motion and the onset of myotendinous junction motion occurred simultaneously regardless of the length of the biceps brachii. That suggests that the between-muscles differences reported in the literature cannot be explained by different muscle passive tension but instead may be attributable to muscle architectural differences.
Keyword Magnetic resonance elastography
Human skeletal muscle
Frame Rate Ultrasound
Elbow Flexor Muscles
Gastrocnemius muscle
Ankle Joint
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: Non HERDC
School of Health and Rehabilitation Sciences Publications
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 19 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 21 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Thu, 29 Aug 2013, 02:00:38 EST by Francois Hug on behalf of School of Health & Rehabilitation Sciences