Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles

Introduction Quantifying neural activation is crucial for evaluating rehabilitation progress and adaptations following resistance training. A commonly used method for assessing voluntary activation (VA) is the Interpolated Twitch Technique with electrical nerve stimulation (ENS). However, this meth...

Full description

Saved in:
Bibliographic Details
Main Authors: Romina Ledergerber, Martin Keller
Format: Article
Language:English
Published: Bern Open Publishing 2025-01-01
Series:Current Issues in Sport Science
Subjects:
Online Access:https://ciss-journal.org/article/view/12028
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832542510232109056
author Romina Ledergerber
Martin Keller
author_facet Romina Ledergerber
Martin Keller
author_sort Romina Ledergerber
collection DOAJ
description Introduction Quantifying neural activation is crucial for evaluating rehabilitation progress and adaptations following resistance training. A commonly used method for assessing voluntary activation (VA) is the Interpolated Twitch Technique with electrical nerve stimulation (ENS). However, this method is often associated with discomfort, limiting its applicability in sensitive populations such as children or patients (Shield & Zhou, 2004). Magnetic nerve stimulation (MNS) offers a painless and promising alternative, but its validity and reliability remain insufficiently established (Verges et al., 2009). This study aims to address this gap by comparing ENS and MNS and assessing the reliability of MNS across sessions. Methods This study compares ENS to MNS (validity) and evaluates inter-session reliability in sixteen healthy young adults (11 females, 5 males). Data on resting single twitches (RS), 3-5 superimposed twitches (ST) during maximal voluntary contractions of knee extensors, and resting doublet twitches (RD) were assessed using both MNS and ENS. Discomfort was assessed using the visual analogue scale (VAS). Intraclass correlation (ICC), Coefficient of variation (CV) and mean absolute percentage error (MAPE) were used to assess measurement precision. Results There was strong agreement between MNS and ENS for RS, RD and VA (ICC=0.77-0.88). Accuracy was confirmed, with MAPE values of 4.4% for VA and 9.5% for RD. The inter-session reliability of MNS was good across all parameters (ICC = 0.78–0.95) with low CV for VA (4.9%) but high CV for RS, RD and ST (61.7%, 28.9%, 82%). Discomfort ratings were significantly lower for MNS (VAS = 1.0 ± 0.9) compared to ENS (VAS = 1.8 ± 1.2). Discussion/Conclusion This study demonstrates that MNS is a valid, reliable, and minimally discomforting alternative to ENS for assessing VA in knee extensor muscles. The use of a positioning arm in our methodology likely enhanced precision within sessions. However, individual twitch measurements varied between methods and sessions, warranting caution when interpreting absolute values. Given its minimal discomfort, MNS is especially suited for studying neuromuscular adaptations in vulnerable populations and should be widely adopted. References Shield, A., & Zhou, S. (2004). Assessing voluntary muscle activation with the twitch interpolation technique. Sports Medicine, 34(4), 253–267. https://doi.org/10.2165/00007256-200434040-00005 Verges, S., Maffiuletti, N. A., Kerherve, H., Decorte, N., Wuyam, B., & Millet, G. Y. (2009). Comparison of electrical and magnetic stimulations to assess quadriceps muscle function. Journal of Applied Physiology, 106(2), 701–710. https://doi.org/10.1152/japplphysiol.01051.2007
format Article
id doaj-art-512e5f66e21941389fc2a178a1b3ea57
institution Kabale University
issn 2414-6641
language English
publishDate 2025-01-01
publisher Bern Open Publishing
record_format Article
series Current Issues in Sport Science
spelling doaj-art-512e5f66e21941389fc2a178a1b3ea572025-02-04T03:15:10ZengBern Open PublishingCurrent Issues in Sport Science2414-66412025-01-0110210.36950/2025.2ciss048Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor MusclesRomina Ledergerber0Martin Keller1Department of Sport, Exercise and Health, SwitzerlandDepartment of Sport, Exercise and Health, Switzerland Introduction Quantifying neural activation is crucial for evaluating rehabilitation progress and adaptations following resistance training. A commonly used method for assessing voluntary activation (VA) is the Interpolated Twitch Technique with electrical nerve stimulation (ENS). However, this method is often associated with discomfort, limiting its applicability in sensitive populations such as children or patients (Shield & Zhou, 2004). Magnetic nerve stimulation (MNS) offers a painless and promising alternative, but its validity and reliability remain insufficiently established (Verges et al., 2009). This study aims to address this gap by comparing ENS and MNS and assessing the reliability of MNS across sessions. Methods This study compares ENS to MNS (validity) and evaluates inter-session reliability in sixteen healthy young adults (11 females, 5 males). Data on resting single twitches (RS), 3-5 superimposed twitches (ST) during maximal voluntary contractions of knee extensors, and resting doublet twitches (RD) were assessed using both MNS and ENS. Discomfort was assessed using the visual analogue scale (VAS). Intraclass correlation (ICC), Coefficient of variation (CV) and mean absolute percentage error (MAPE) were used to assess measurement precision. Results There was strong agreement between MNS and ENS for RS, RD and VA (ICC=0.77-0.88). Accuracy was confirmed, with MAPE values of 4.4% for VA and 9.5% for RD. The inter-session reliability of MNS was good across all parameters (ICC = 0.78–0.95) with low CV for VA (4.9%) but high CV for RS, RD and ST (61.7%, 28.9%, 82%). Discomfort ratings were significantly lower for MNS (VAS = 1.0 ± 0.9) compared to ENS (VAS = 1.8 ± 1.2). Discussion/Conclusion This study demonstrates that MNS is a valid, reliable, and minimally discomforting alternative to ENS for assessing VA in knee extensor muscles. The use of a positioning arm in our methodology likely enhanced precision within sessions. However, individual twitch measurements varied between methods and sessions, warranting caution when interpreting absolute values. Given its minimal discomfort, MNS is especially suited for studying neuromuscular adaptations in vulnerable populations and should be widely adopted. References Shield, A., & Zhou, S. (2004). Assessing voluntary muscle activation with the twitch interpolation technique. Sports Medicine, 34(4), 253–267. https://doi.org/10.2165/00007256-200434040-00005 Verges, S., Maffiuletti, N. A., Kerherve, H., Decorte, N., Wuyam, B., & Millet, G. Y. (2009). Comparison of electrical and magnetic stimulations to assess quadriceps muscle function. Journal of Applied Physiology, 106(2), 701–710. https://doi.org/10.1152/japplphysiol.01051.2007 https://ciss-journal.org/article/view/12028Magnetic nerve stimulationvoluntary activationneural drivevalidityinter-session reliability
spellingShingle Romina Ledergerber
Martin Keller
Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
Current Issues in Sport Science
Magnetic nerve stimulation
voluntary activation
neural drive
validity
inter-session reliability
title Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
title_full Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
title_fullStr Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
title_full_unstemmed Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
title_short Inter-session Reliability of Magnetic Nerve Stimulation and Within-Session comparison to Electrical Nerve Stimulation in Evaluating Neuromuscular Function of Knee Extensor Muscles
title_sort inter session reliability of magnetic nerve stimulation and within session comparison to electrical nerve stimulation in evaluating neuromuscular function of knee extensor muscles
topic Magnetic nerve stimulation
voluntary activation
neural drive
validity
inter-session reliability
url https://ciss-journal.org/article/view/12028
work_keys_str_mv AT rominaledergerber intersessionreliabilityofmagneticnervestimulationandwithinsessioncomparisontoelectricalnervestimulationinevaluatingneuromuscularfunctionofkneeextensormuscles
AT martinkeller intersessionreliabilityofmagneticnervestimulationandwithinsessioncomparisontoelectricalnervestimulationinevaluatingneuromuscularfunctionofkneeextensormuscles