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Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation
Published on: September 13, 2015
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Interleaved neuromuscular electrical stimulation reduces muscle fatigue
Jenny W H Lou1, Austin J Bergquist2, Abdulaziz Aldayel3
1Human Neurophysiology Laboratory, Faculty of Physical Education and Recreation, University of Alberta, E-488 Van Vliet Centre, Edmonton, Alberta, T6G 2H9, Canada.
Muscle & Nerve
|June 18, 2016
Summary
Interleaved neuromuscular electrical stimulation (iNMES) reduces muscle fatigue by alternating stimulation between muscle and nerve. This novel approach, iNMES, offers a promising method for enhancing NMES-based rehabilitation by lowering motor unit discharge frequencies.
Area of Science:
- Rehabilitation Medicine
- Neuroscience
- Biomedical Engineering
Background:
- Neuromuscular electrical stimulation (NMES) is used in rehabilitation.
- Conventional NMES methods (muscle belly or nerve trunk) cause rapid muscle fatigue due to high motor unit discharge rates.
Purpose of the Study:
- To introduce and evaluate interleaved NMES (iNMES) as a method to reduce muscle fatigue.
- To compare the fatigue-inducing effects of iNMES against traditional mNMES and nNMES.
Main Methods:
- Developed interleaved NMES (iNMES) by alternating stimulus pulses between muscle and nerve.
- Conducted 12-minute fatigue protocols with 240 contractions using mNMES, nNMES, and iNMES.
- Recorded torque and electromyography to assess muscle fatigue.
Main Results:
- Torque declined significantly by 3 minutes with iNMES, compared to 1 minute for mNMES and nNMES.
- Torque decreased by 39% with iNMES, versus 67% for mNMES and 58% for nNMES.
- iNMES demonstrated significantly less muscle fatigue compared to mNMES and nNMES.
Conclusions:
- Interleaved NMES (iNMES) effectively reduces muscle fatigue compared to conventional methods.
- Modulating motor unit discharge frequencies through novel NMES delivery holds potential for improved rehabilitation outcomes.
- iNMES presents a promising alternative for reducing muscle fatigue in NMES applications.
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