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Updated: Mar 8, 2026
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Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
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Fatigability in Patients With Multiple Sclerosis During Maximal Concentric Contractions.
Sophie Hameau1, Djamel Bensmail1, Nicolas Roche2
1Inserm Unit 1179, Team 3: Technology and Innovative Therapies Applied to Neuromuscular Diseases, University of Versailles Saint Quentin en Yvelines, Garches, France; Department of Physical Medicine and Rehabilitation, R. Poincaré Hospital, Garches, France.
Archives of Physical Medicine and Rehabilitation
|January 29, 2017
Summary
Individuals with multiple sclerosis (MS) experience less quadriceps muscle fatigability than healthy individuals during maximal contractions. Despite this, both groups conclude the fatigue protocol at a similar relative strength level.
Area of Science:
- Neurology
- Rehabilitation Medicine
- Exercise Physiology
Background:
- Fatigue is a common and disabling symptom in multiple sclerosis (MS).
- Understanding muscle fatigability is crucial for managing MS-related functional decline.
Purpose of the Study:
- To compare quadriceps fatigability during maximal concentric contractions in persons with MS and healthy subjects.
- To investigate the neuromuscular mechanisms underlying fatigue in MS.
Main Methods:
- An observational study involving 38 persons with MS and 14 healthy controls.
- Isokinetic evaluation of knee flexor and extensor muscles, assessing fatigability of knee extensors.
- Surface electromyography recorded for key leg muscles.
Main Results:
- Persons with MS demonstrated a lower torque fatigue index compared to healthy subjects.
- When normalized, both groups reached 50% of their maximal isometric peak torque.
- Reduced neuromuscular efficiency, not increased antagonist coactivation, primarily explained torque reduction in MS.
Conclusions:
- Persons with MS exhibit less muscle fatigability than healthy individuals during maximal concentric contractions.
- Despite lower fatigability, individuals with MS maintain the same relative strength post-fatigue as controls.
- Neuromuscular efficiency is a key factor in fatigue response in MS.
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