Dataset Information

Improving the measurement of TMS-assessed voluntary activation in the knee extensors.

ABSTRACT:

Purpose

To test the accuracy, validity, reliability and sensitivity of an alternative method for the measure of TMS-assessed voluntary activation (VATMS) in the knee extensors.

Methods

Ten healthy males (24 ± 5 years) completed a neuromuscular assessment protocol before and after a fatiguing isometric exercise: two sets of five contractions (50%, 62.5%, 75%, 87.5%, 100% Maximal Voluntary Contraction; MVC) with superimposed TMS-evoked twitches for calculation of VATMS using either the first 5 stimulations (1x5C) or all 10 (2x5C). This was performed on two separate occasions (between-day reliability). Accuracy and validity were compared with a routinely used protocol [i.e. 50%, 75%, and 100% of MVC (1x3C) performed three times (3x3C)].

Results

95% confidence interval for estimated resting twitch, a key determinant of VATMS, was similar between 1x5C, 2x5C, and 3x3C but improved by six-fold when compared to 1x3C (P<0.05). In a fresh state, potentiated twitch force was unchanged following 1x5C but decreased following 2x5C (P<0.05). A recovery was found post-exercise but was smaller for 1x5C compared to 2x5C (P<0.05), with no difference between the latter two (P>0.05). Absolute reliability was strong enough for both 1x5C and 2x5C to depict a true detectable change in the sample's VATMS following the fatiguing exercise (TEM < 3% at rest, <9% post-exercise) but 2x5C was marginally more sensitive to individual's changes from baseline.

Conclusion

Both 1x5C and 2x5C provide reliable measures of VATMS. However, 1x5C may hold stronger internal validity. Both protocols allow detection of 'true' changes in sample's means but not individual scores following a fatiguing isometric exercise.

SUBMITTER: Dekerle J

PROVIDER: S-EPMC6553714 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Improving the measurement of TMS-assessed voluntary activation in the knee extensors.

Dekerle Jeanne J Greenhouse-Tucknott Aaron A Wrightson James G JG Schäfer Lisa L Ansdell Paul P

PloS one 20190606 6

<h4>Purpose</h4>To test the accuracy, validity, reliability and sensitivity of an alternative method for the measure of TMS-assessed voluntary activation (VATMS) in the knee extensors.<h4>Methods</h4>Ten healthy males (24 ± 5 years) completed a neuromuscular assessment protocol before and after a fatiguing isometric exercise: two sets of five contractions (50%, 62.5%, 75%, 87.5%, 100% Maximal Voluntary Contraction; MVC) with superimposed TMS-evoked twitches for calculation of VATMS using either ...[more]

PMID: 31170180

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Dataset Information

Improving the measurement of TMS-assessed voluntary activation in the knee extensors.

Purpose

Methods

Results

Conclusion

Publications

Improving the measurement of TMS-assessed voluntary activation in the knee extensors.

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