Boys-men mean-power-frequency differences in progressive exercise to exhaustion, confounded by variability and adiposity.
Child–adult differences
EMG threshold
Endurance
Fatigue
Motor-unit activation
Neuromotor control
Journal
European journal of applied physiology
ISSN: 1439-6327
Titre abrégé: Eur J Appl Physiol
Pays: Germany
ID NLM: 100954790
Informations de publication
Date de publication:
09 Aug 2023
09 Aug 2023
Historique:
received:
02
03
2023
accepted:
26
07
2023
medline:
9
8
2023
pubmed:
9
8
2023
entrez:
8
8
2023
Statut:
aheadofprint
Résumé
Only scant research has compared children's mean power frequency (MPF) to adults', with a clear overview still lacking. A significant obstacle has been MPF's high variability, which this study aimed to overcome by elucidating the MPF characteristics distinguishing boys from men in progressive exhaustive exercise. Electromyographic (EMG) data of 20 men (23.5 ± 2.5yrs) and 17 boys (10.2 ± 1.0 yrs), who performed progressively exhausting, intermittent isometric knee extensions, were subjected to secondary MPF analysis. Participants' vastus lateralis MPF data series were transformed to third-order polynomial regressions and expressed as percentages of the peak polynomial MPF values (%MPF No overall interaction or group effects could be shown between the %MPF The boys were lower than the men in both the observed and, more so, in the adiposity-corrected MPF values that presumably estimate muscle-level MPF. The boys' shallower MPF rise and decline conform to children's claimed type-II motor-unit activation and/or compositional deficits and their related known advantage in muscular endurance.
Sections du résumé
BACKGROUND
BACKGROUND
Only scant research has compared children's mean power frequency (MPF) to adults', with a clear overview still lacking. A significant obstacle has been MPF's high variability, which this study aimed to overcome by elucidating the MPF characteristics distinguishing boys from men in progressive exhaustive exercise.
METHODS
METHODS
Electromyographic (EMG) data of 20 men (23.5 ± 2.5yrs) and 17 boys (10.2 ± 1.0 yrs), who performed progressively exhausting, intermittent isometric knee extensions, were subjected to secondary MPF analysis. Participants' vastus lateralis MPF data series were transformed to third-order polynomial regressions and expressed as percentages of the peak polynomial MPF values (%MPF
RESULTS
RESULTS
No overall interaction or group effects could be shown between the %MPF
CONCLUSIONS
CONCLUSIONS
The boys were lower than the men in both the observed and, more so, in the adiposity-corrected MPF values that presumably estimate muscle-level MPF. The boys' shallower MPF rise and decline conform to children's claimed type-II motor-unit activation and/or compositional deficits and their related known advantage in muscular endurance.
Identifiants
pubmed: 37553549
doi: 10.1007/s00421-023-05292-3
pii: 10.1007/s00421-023-05292-3
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Informations de copyright
© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
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