Percent voluntary inactivation and peak force predictions with the interpolated twitch technique in individuals with high ability of voluntary activation

Trent J. Herda, Ashley A. Walter, Pablo B. Costa, Eric D. Ryan, Katherine M. Hoge, Jeffrey R. Stout, Joel T. Cramer

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

The purpose of this study was to examine the sensitivity and peak force prediction capability of the interpolated twitch technique (ITT) performed during submaximal and maximal voluntary contractions (MVCs) in subjects with the ability to maximally activate their plantar flexors. Twelve subjects performed two MVCs and nine submaximal contractions with the ITT method to calculate percent voluntary inactivation (%VI). Additionally, two MVCs were performed without the ITT. Polynomial models (linear, quadratic and cubic) were applied to the 10-90% VI and 40-90% VI versus force relationships to predict force. Peak force from the ITT MVC was 6.7% less than peak force from the MVC without the ITT. Fifty-eight percent of the 10-90% VI versus force relationships were best fit with nonlinear models; however, all 40-90% VI versus force relationships were best fit with linear models. Regardless of the polynomial model or the contraction intensities used to predict force, all models underestimated the actual force from 22% to 28%. There was low sensitivity of the ITT method at high contraction intensities and the predicted force from polynomial models significantly underestimated the actual force. Caution is warranted when interpreting the % VI at high contraction intensities and predicted peak force from submaximal contractions.

Original languageEnglish (US)
Pages (from-to)1591-1603
Number of pages13
JournalPhysiological Measurement
Volume32
Issue number10
DOIs
StatePublished - Oct 2011
Externally publishedYes

ASJC Scopus subject areas

  • Biophysics
  • Physiology
  • Biomedical Engineering
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Percent voluntary inactivation and peak force predictions with the interpolated twitch technique in individuals with high ability of voluntary activation'. Together they form a unique fingerprint.

Cite this