A1 Journal article (refereed)
Test–retest reliability of cortico-spinal measurements in the rectus femoris at different contraction levels (2023)

Gomez-Guerrero, G., Avela, J., Enroth, M., Häkkinen, E., Ansdell, P., Howatson, G., & Walker, S. (2023). Test–retest reliability of cortico-spinal measurements in the rectus femoris at different contraction levels. Frontiers in Neuroscience, 17, Article 1239982. https://doi.org/10.3389/fnins.2023.1239982

JYU authors or editors

Publication details

All authors or editors: Gomez-Guerrero, Gonzalo; Avela, Janne; Enroth, Miro; Häkkinen, Ella; Ansdell, Paul; Howatson, Glyn; Walker, Simon

Journal or series: Frontiers in Neuroscience

ISSN: 1662-4548

eISSN: 1662-453X

Publication year: 2023

Publication date: 02/10/2023

Volume: 17

Article number: 1239982

Publisher: Frontiers Media SA

Publication country: Switzerland

Publication language: English

DOI: https://doi.org/10.3389/fnins.2023.1239982

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/89387

Abstract

Single-pulse Transcranial Magnetic Stimulation (TMS) and, very recently, lumbar stimulation (LS) have been used to measure cortico-spinal excitability from various interventions using maximal or submaximal contractions in the lower limbs. However, reliability studies have overlooked a wide range of contraction intensities for MEPs, and no reliability data is available for LEPs. This study investigated the reliability of motor evoked potentials and lumbar evoked potentials at different stimulation intensities and contraction levels in m.rectus femoris. Twenty-two participants performed non-fatiguing isometric knee extensions at 20 and 60% of maximum voluntary contraction (MVC). LS induced a lumbar-evoked potential (LEP) of 25 and 50% resting maximal compound action potential (M-max). TMS stimulator output was adjusted to 120, 140, and 160% of active motor threshold (aMT). In each contraction, a single MEP or LEP was delivered. Ten contractions were performed at each stimulator intensity and contraction level in random order. Moderate-to-good reliability was found when LEP was normalized to M-max/ Root Mean Square in all conditions (ICC:0.74–0.85). Excellent reliability was found when MEP was normalized to Mmax for all conditions (ICC  >  0.90) at 60% of MVC. Good reliability was found for the rest of the TMS conditions. Moderateto-good reliability was found for silent period (SP) elicited by LS (ICC: 0.71–0.83). Good-to-excellent reliability was found for SP elicited by TMS (ICC  >  0.82). MEPs and LEPs elicited in m.rectus femoris appear to be reliable to assess changes at different segments of the cortico-spinal tract during different contraction levels and stimulator output intensities. Furthermore, the TMS- and LS- elicited SP was a reliable tool considered to reflect inhibitory processes at spinal and cortical levels.

Keywords: neuromuscular activity; stimulation; transcranial magnetic stimulation; measuring methods; reliability (science)

Free keywords: reliability; lumbar stimulation; spinal excitability; silent period; cortico-spinal tract; lower limb; knee extensors

Contributing organizations

Ministry reporting: Yes

VIRTA submission year: 2023

JUFO rating: 1