ArticleThe Journal of physiology2009
Fluctuations in isometric muscle force can be described by one linear projection of low-frequency components of motor unit discharge rates.
Article in The Journal of physiology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 131 papers, 2 of them syntheses that pooled it.
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Who cites it
131 citing papers in PubMed, 2 syntheses or guidelines pooled it.
- Does pain influence control of muscle force? A systematic review and meta-analysis.European journal of pain (London, England) · 2025Pooled it
- Can Resistance Training Improve Upper Limb Postural Tremor, Force Steadiness and Dexterity in Older Adults? A Systematic Review.Sports medicine (Auckland, N.Z.) · 2019Pooled it
- Differential training benefits and motor unit remodeling in wrist force precision tasks following high and low load blood flow restriction exercises under volume-matched conditions.Journal of neuroengineering and rehabilitation · 2024Trial
- Mental fatigue impairs physical performance but not the neural drive to the muscle: a preliminary analysis.European journal of applied physiology · 2023Trial
- Low-frequency oscillations of the neural drive to the muscle are increased with experimental muscle pain.Journal of neurophysiology · 2012Trial
- Dual-Tasking Exacerbates Force and Neural Control Unsteadiness in Older Adults With Sarcopenia.Journal of cachexia, sarcopenia and muscle · 2026Article
- Differential changes in the effective neural drive following new motor skill acquisition between vastus lateralis and medialis.European journal of applied physiology · 2026Article
- Estimation of persistent inward currents contribution to inspiratory motoneuron firing in humans.The Journal of physiology · 2026Article
- Modulation of Hamstrings Neural Drive During Isometric Contractions of the Hip Extensors and Knee Flexors.Scandinavian journal of medicine & science in sports · 2026Article
- Reduced knee extensor torque steadiness and increased motor unit discharge rate variability in young people with patellofemoral pain: a pilot study.European journal of applied physiology · 2026Article
- The Effects of an Acute Strongman Competition on Electromyographic Responses of the Shoulder Girdle Complex.Life (Basel, Switzerland) · 2026Article
- Age-related alterations in trunk extensor force control during isometric and isokinetic contractions.Scientific reports · 2026Article
- Independent neural drives and distinct motor unit discharge characteristics in hamstring muscles during isometric knee flexion.European journal of applied physiology · 2026Article
- Adaptation of motor unit synergies in the synergetic ankle plantarflexors in ambulatory persons with incomplete spinal cord injury.Journal of neuroengineering and rehabilitation · 2026Article
- Reassessment of isometric muscle force complexity under different contraction intensities, joint angles, and visual feedback conditions.European journal of applied physiology · 2025Article
- Characterization of motor unit activities during isometric elbow flexion with different speeds.Journal of neuroengineering and rehabilitation · 2025Article
- A single low-dimensional neural component of spinal motor neuron activity explains force generation across repetitive isometric tasks.iScience · 2025Article
- Exploring the role of ankle torque fluctuations and intramuscular coherence in gait function among older adults.Aging clinical and experimental research · 2025Article
- Neuromuscular control of a five-finger pinch task is influenced by training history.Experimental brain research · 2025Article
- Projection of Cortical Beta Band Oscillations to a Motor Neuron Pool across the Full Range of Recruitment.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2025Article
71 more citing papers are in PubMed but not listed here.
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The aim of the study was to investigate the relation between linear transformations of motor unit discharge rates and muscle force. Intramuscular (wire electrodes) and high-density surface EMG (13 x 5 electrode grid) were recorded from the abductor digiti minimi muscle of eight healthy men during 60 s contractions at 5%, 7.5% and 10% of the maximal force. Spike trains of a total of 222 motor units were identified from the EMG recordings with decomposition algorithms. Principal component analysis of the smoothed motor unit discharge rates indicated that one component (first common component, FCC) described 44.2 +/- 7.5% of the total variability of the smoothed discharge rates when computed over the entire contraction interval and 64.3 +/- 10.2% of the variability when computed over 5 s intervals. When the FCC was computed from four or more motor units per contraction, it correlated with the force produced by the muscle (62.7 +/- 10.1%) by a greater degree (P < 0.001) than the smoothed discharge rates of individual motor units (41.4 +/- 7.8%). The correlation between FCC and the force signal increased up to 71.8 +/- 13.1% when the duration and the shape of the smoothing window for discharge rates were similar to the average motor unit twitch force. Moreover, the coefficients of variation (CoV) for the force and for the FCC signal were correlated in all subjects (R(2) range = 0.14-0.56; P < 0.05) whereas the CoV for force was correlated to the interspike interval variability in only one subject (R(2) = 0.12; P < 0.05). Similar results were further obtained from measures on the tibialis anterior muscle of an additional eight subjects during contractions at forces up to 20% of the maximal force (e.g. FCC explained 59.8 +/- 11.0% of variability of the smoothed discharge rates). In conclusion, one signal captures most of the underlying variability of the low-frequency components of motor unit discharge rates and explains large part of the fluctuations in the motor output during isometric contractions.
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