ArticleJournal of applied physiology (Bethesda, Md. : 1985)2009
Motor unit control and force fluctuation during fatigue.
Article in Journal of applied physiology (Bethesda, Md. : 1985), 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 50 papers, 1 of them a synthesis that pooled it.
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Who cites it
50 citing papers in PubMed, 1 synthesis or guideline pooled it, 163 citations in OpenAlex.
- The use of non-linear tools to analyze the variability of force production as an index of fatigue: A systematic review.Frontiers in physiology · 2022Pooled it
- Marine Phytoplankton Improves Exercise Recovery in Humans and Activates Repair Mechanisms in Rats.International journal of sports medicine · 2021Trial
- [Research on a muscle fatigue quantification based on an improved critical power model].Sheng wu yi xue gong cheng xue za zhi = Journal of biomedical engineering = Shengwu yixue gongchengxue zazhi · 2026Article
- Blood flow restriction modulates common drive to motor units and force precision: implications for neuromuscular coordination.European journal of applied physiology · 2026Article
- Force fluctuations regulation and the role of neurophysiological mechanisms throughout different isometric contraction intensities.Scientific reports · 2025Article
- Neuromuscular fatigue reduces force responsiveness when controlling leg external forces.Physiological reports · 2025Article
- The neuromechanical delay of the quadriceps shortens with increasing contraction intensity.Scientific reports · 2025Article
- Changes in muscle oxygenation and activity during cumulative isometric muscle contraction: new insight into muscle fatigue.Frontiers in physiology · 2025Article
- Alpha band oscillations in common synaptic input are explanatory of the complexity of isometric knee extensor muscle torque signals.Experimental physiology · 2024Article
- Boys-men mean-power-frequency differences in progressive exercise to exhaustion, confounded by variability and adiposity.European journal of applied physiology · 2024Article
- A comparison of individual force decline profiles during a fatiguing eccentric trunk flexion and extension protocol: a pilot study.Frontiers in sports and active living · 2024Article
- A comparison of techniques for verifying the accuracy of precision decomposition-derived relationships between motor unit firing rates and recruitment thresholds from surface EMG signals.Experimental brain research · 2023Article
- The Back Muscle Surface Electromyography-Based Fatigue Index: A Digital Biomarker of Human Neuromuscular Aging?Bioengineering (Basel, Switzerland) · 2023Article
- The influence of chronic training status on the mechanical behavior of the vastus lateralis during repetitive trapezoidal contractions.Journal of musculoskeletal & neuronal interactions · 2022Article
- Effect of New Zealand Blackcurrant Extract on Force Steadiness of the Quadriceps Femoris Muscle during Sustained Submaximal Isometric Contraction.Journal of functional morphology and kinesiology · 2022Article
- The Influence of the sEMG Amplitude Estimation Technique on the EMG-Force Relationship.Sensors (Basel, Switzerland) · 2022Article
- Effects of Fatigue on Postural Sway and Electromyography Modulation in Young Expert Acrobatic Gymnasts and Healthy Non-trained Controls During Unipedal Stance.Frontiers in physiology · 2022Article
- Examining Additional Aspects of Muscle Function with a Digital Handgrip Dynamometer and Accelerometer in Older Adults: A Pilot Study.Geriatrics (Basel, Switzerland) · 2020Article
- A model-based estimation of critical torques reduces the experimental effort compared to conventional testing.European journal of applied physiology · 2020Article
- Fatigue-related modulation of low-frequency common drive to motor units.European journal of applied physiology · 2020Article
Corrections and comments
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
Abstract
During isometric contractions, the fluctuation of the force output of muscles increases as the muscle fatigues, and the contraction is sustained to exhaustion. We analyzed motor unit firing data from the vastus lateralis muscle to investigate which motor unit control parameters were associated with the increased force fluctuation. Subjects performed a sequence of isometric constant-force contractions sustained at 20% maximal force, each spaced by a 6-s rest period. The contractions were performed until the mean value of the force output could not be maintained at the desired level. Intramuscular EMG signals were detected with a quadrifilar fine-wire sensor. The EMG signals were decomposed to identify all of the firings of several motor units by using an artificial intelligence-based set of algorithms. We were able to follow the behavior of the same motor units as the endurance time progressed. The force output of the muscle was filtered to remove contributions from the tracking task. The coefficient of variation of the force was found to increase with endurance time (P < 0.001, R(2) = 0.51). We calculated the coefficient of variation of the firing rates, the synchronization of pairs of motor unit firings, the cross-correlation value of the firing rates of pairs of motor units, the cross-correlation of the firing rates of motor units and the force, and the number of motor units recruited during the contractions. Of these parameters, only the cross-correlation of the firing rates (P < 0.01, R(2) = 0.10) and the number of recruited motor units (P = 0.042, R(2) = 0.22) increased significantly with endurance time for grouped subjects. A significant increase (P < 0.001, R(2) = 0.16) in the cross-correlation of the firing rates and force was also observed. It is suggested that the increase in the cross-correlation of the firing rates is likely due to a decrease in the sensitivity of the proprioceptive feedback from the spindles.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.