Alternate muscle activity patterns among synergists of the quadriceps femoris including the vastus intermedius during low-level sustained contraction in men
Article first published online: 29 MAY 2012
Copyright © 2012 Wiley Periodicals, Inc.
Muscle & Nerve
Volume 46, Issue 1, pages 86–95, July 2012
How to Cite
Akima, H., Saito, A., Watanabe, K. and Kouzaki, M. (2012), Alternate muscle activity patterns among synergists of the quadriceps femoris including the vastus intermedius during low-level sustained contraction in men. Muscle Nerve, 46: 86–95. doi: 10.1002/mus.23268
- Issue published online: 12 JUN 2012
- Article first published online: 29 MAY 2012
- Accepted manuscript online: 5 DEC 2011 06:28AM EST
- Manuscript Accepted: 1 DEC 2011
- neuromuscular modulation;
- quadriceps femoris;
- surface EMG;
- vastus intermedius
We quantified the alternate muscle activity among four synergists of the quadriceps femoris (QF), including the vastus intermedius (VI), during low-level sustained contraction.
Surface electromyograms (EMGs) were recorded from the VI, vastus lateralis (VL), vastus medialis (VM), and rectus femoris (RF) in 11 healthy men during isometric knee extension at 2.5% maximum voluntary contraction for 60 min to determine alternate muscle activity among the four synergists of the QF.
Alternate activity was primarily found between the RF and VI, VL, or VM, and rarely found among the vasti muscles. Multiple muscle comparison revealed the duration of alternate activity in the RF/VI+VL+VM combination remained high throughout the experiment, although the frequency of that combination did not.
These results suggested that there is a fixed muscle combination, i.e., RF and the 3 vasti muscles, to perform low-intensity sustained contraction in the human QF. Muscle Nerve 46: 86–95, 2012