ArticleGeroScience2021
Intrinsic motoneuron excitability is reduced in soleus and tibialis anterior of older adults.
Article in GeroScience, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 28 papers, 1 of them a synthesis that pooled it.
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Who cites it
28 citing papers in PubMed, 1 synthesis or guideline pooled it, 53 citations in OpenAlex.
- A Systematic Review of Surface Electromyography in Sarcopenia: Muscles Involved, Signal Processing Techniques, Significant Features, and Artificial Intelligence Approaches.Sensors (Basel, Switzerland) · 2025Pooled it
- Age-related differences in motor unit discharge rate modulation across contraction levels.GeroScience · 2026Article
- Dual-Tasking Exacerbates Force and Neural Control Unsteadiness in Older Adults With Sarcopenia.Journal of cachexia, sarcopenia and muscle · 2026Article
- Efficient Suprahyoid Muscle Contraction by Combined Modulated Currents in Mice.The Laryngoscope · 2026Article
- Estimation of persistent inward currents contribution to inspiratory motoneuron firing in humans.The Journal of physiology · 2026Article
- Ageing does not impair motor neuron adaptations: comparable motor unit responses to strength training in young and older adults.The Journal of physiology · 2026Article
- SK channel upregulation and sex-specific mechanisms drive spinal motoneuron reduced excitability with age.Frontiers in aging neuroscience · 2026Article
- Intrinsic Motoneuron Excitability Differentiates Sarcopenic, Nonsarcopenic and Athletic Ageing Phenotypes.Journal of cachexia, sarcopenia and muscle · 2025Article
- Changes in eccentric hamstring strength and muscle soreness in younger and older male football players following match play.BMC sports science, medicine & rehabilitation · 2025Article
- Is soleus intrinsic motor neuron excitability contributing to motor deficits in runners with Achilles tendinopathy?European journal of applied physiology · 2025Article
- Pathophysiology of voluntary motor commands at the level of the spinal motoneuron in patients with multiple sclerosis.medRxiv : the preprint server for health sciences · 2025Article
- Sex and Age-Related Changes in Lean Mass of C57BL/6 Mice: A New Method for Assessing Body Composition.Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference · 2025Article
- Motor unit adaptation to disuse: crossing the threshold from firing rate suppression to neuromuscular junction transmission.The Journal of physiology · 2025Review
- In vivo estimation of motor unit intrinsic properties in individuals with spinal cord injury.Journal of neuroengineering and rehabilitation · 2025Article
- 5-HTGeroScience · 2025Article
- Age-related increase in the excitability of mouse layer V pyramidal neurons in the primary motor cortex is accompanied by an increased persistent inward current.GeroScience · 2025Article
- Can non-invasive motor unit analysis reveal distinct neural strategies of force production in young with uncomplicated type 1 diabetes?European journal of applied physiology · 2025Article
- Article
- Minimum Electromyography Sensor Set Needed to Identify Age-Related Impairments in the Neuromuscular Control of Walking Using the Dynamic Motor Control Index.Sensors (Basel, Switzerland) · 2024Article
- Multi-channel EMG manifestations of upper-extremity muscle coordination imbalance among community-dwelling sarcopenic seniors.Biomedical engineering online · 2024Article
Corrections and comments
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Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Age-related deterioration within both motoneuron and monoaminergic systems should theoretically reduce neuromodulation by weakening motoneuronal persistent inward current (PIC) amplitude. However, this assumption remains untested. Surface electromyographic signals were collected using two 32-channel electrode matrices placed on soleus and tibialis anterior of 25 older adults (70 ± 4 years) and 17 young adults (29 ± 5 years) to investigate motor unit discharge behaviors. Participants performed triangular-shaped plantar and dorsiflexion contractions to 20% of maximum torque at a rise-decline rate of 2%/s of each participant's maximal torque. Pairwise and composite paired-motor unit analyses were adopted to calculate delta frequency (ΔF), which has been used to differentiate between the effects of synaptic excitation and intrinsic motoneuronal properties and is assumed to be proportional to PIC amplitude. Soleus and tibialis anterior motor units in older adults had lower ΔFs calculated with either the pairwise [-0.99 and -1.46 pps; -35.4 and -33.5%, respectively] or composite (-1.18 and -2.28 pps; -32.1 and -45.2%, respectively) methods. Their motor units also had lower peak discharge rates (-2.14 and -2.03 pps; -19.7 and -13.9%, respectively) and recruitment thresholds (-1.50 and -2.06% of maximum, respectively) than young adults. These results demonstrate reduced intrinsic motoneuron excitability during low-force contractions in older adults, likely mediated by decreases in the amplitude of persistent inward currents. Our findings might be explained by deterioration in the motoneuron or monoaminergic systems and could contribute to the decline in motor function during aging; these assumptions should be explicitly tested in future investigations.
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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.