Evidence map›Paper›PMID 41648633›Full record

ArticlebioRxiv : the preprint server for biology2026

Motor unit discharge properties are modestly influenced by menstrual cycle-related fluctuations in sex hormone concentrations.

Sophia T Jenz, Pádraig Spillane, Mollie O'Hanlon, Elisa Nédélec, MUSH Collaboration, C J Heckman, Mathew Piasecki, Paul Ansdell, Jessica Piasecki, Gregory E P Pearcey

Abstract readPreprint
In one paragraph

Article in bioRxiv : the preprint server for biology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Sophia T JenzDepartment of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, USA.ORCID 0000-0003-3150-1281
Pádraig SpillaneSchool of Sport, Exercise, and Rehabilitation, Faculty of Health and Wellbeing, Northumbria University, Newcastle Upon Tyne, UK.
Mollie O'HanlonSport Health and Performance Enhancement (SHAPE) Research Centre, Department of Sport Science, Nottingham Trent University, Nottingham, UK.
Elisa NédélecSchool of Sport, Exercise, and Rehabilitation, Faculty of Health and Wellbeing, Northumbria University, Newcastle Upon Tyne, UK.
MUSH Collaboration
C J HeckmanDepartment of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, USA.ORCID 0000-0002-1324-7278
Mathew PiaseckiCentre of Metabolism, Ageing and Physiology (CoMAP), NIHR Nottingham Biomedical Research Centre, University of Nottingham, Nottingham, UK.ORCID 0000-0002-7804-4631
Paul AnsdellSchool of Sport, Exercise, and Rehabilitation, Faculty of Health and Wellbeing, Northumbria University, Newcastle Upon Tyne, UK.ORCID 0000-0001-7542-1107
Jessica PiaseckiSport Health and Performance Enhancement (SHAPE) Research Centre, Department of Sport Science, Nottingham Trent University, Nottingham, UK.ORCID 0000-0001-9758-6295
Gregory E P PearceySchool of Human Kinetics and recreation, Memorial University of Newfoundland, St. Johns, Canada.ORCID 0000-0002-6751-4351

Funding

Identifying mechanisms underlying sex differences in motoneuron dischargeF31NS130767 · NINDS · NORTHWESTERN UNIVERSITY AT CHICAGO · PI JENZ, SOPHIA THERESA · 2023 to 2025
$119k
NINDS NIH HHS F31 NS130767
6 · The paper itself

Abstract

Concentrations of estradiol (E2) and progesterone (P4), the main female sex hormones, exhibit large fluctuations across the menstrual cycle. Due to their receptors throughout the central nervous system, both hormones have the potential to influence motor function by influencing ionotropic and metabotropic inputs to motor pools, which can be estimated through the neural codes extracted from motor unit discharge patterns. To address key methodological limitations in prior menstrual cycle research on motor output, we established the Motor Units and Sex Hormones (MUSH) collaboration. The objective of this multi-site investigation was to determine whether endogenous fluctuations in estradiol and progesterone influence human motor unit activity. We hypothesized that motor unit discharge rates and persistent inward current (PIC)-related contributions to discharge would be greatest during the late follicular phase, when estradiol concentrations were highest. Fifty females completed a comprehensive protocol involving menstrual cycle and ovulation tracking, serum hormone measurement, and high-density surface electromyographic recordings during isometric contractions to quantify motor unit activity in the early follicular, late follicular, and mid luteal phases. After exclusion of 10 females with either atypical hormone concentration profiles or insufficient motor unit yield, 40 remained in the final analysis. There were significant changes in several motor unit discharge variables between menstrual cycle phases and significant associations with hormone concentrations. Increased estradiol was associated with higher peak discharge rates and ascending discharge rate nonlinearity, while increased progesterone was associated with higher peak discharge rates, more discharge rate hysteresis and ascending discharge rate nonlinearity. Despite reaching statistical significance, the magnitudes of these effects (i.e., effect sizes) were small. Overall, these findings indicate that fluctuations in sex hormones influence motor unit behavior, but the effects are subtle, highlighting the need for well-powered and methodologically rigorous menstrual cycle research.

Identifiers

PMID41648633
PMCPMC12871738

What OpenQuestion holds

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LicenceCC BY
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Registered trials

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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.