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Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions

OBJECTIVES: This study examined effects of acute hypoxia on the neuromuscular responses (electromyographic (EMG) amplitude and EMG frequency) and localized muscle tissue oxygenated hemoglobin (oxygenated hemoglobin (Oxy(Hb)), deoxygenated hemoglobin (Deoxy(Hb)), total hemoglobin (Total(Hb)), and mus...

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Autores principales: Smith, Cory M., Salmon, Owen F., Jenkins, Jasmin R.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: International Society of Musculoskeletal and Neuronal Interactions 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9976181/
https://www.ncbi.nlm.nih.gov/pubmed/36856097
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author Smith, Cory M.
Salmon, Owen F.
Jenkins, Jasmin R.
author_facet Smith, Cory M.
Salmon, Owen F.
Jenkins, Jasmin R.
author_sort Smith, Cory M.
collection PubMed
description OBJECTIVES: This study examined effects of acute hypoxia on the neuromuscular responses (electromyographic (EMG) amplitude and EMG frequency) and localized muscle tissue oxygenated hemoglobin (oxygenated hemoglobin (Oxy(Hb)), deoxygenated hemoglobin (Deoxy(Hb)), total hemoglobin (Total(Hb)), and muscle tissue oxygenation saturation (StO(2)) during the process of fatigue. METHODS: Fifteen male participants (21.4±2.8yr) performed leg extension repetitions to failure at 70% 1-repetition maximum until volitional exhaustion under Normoxic (FiO(2):21%) and Hypoxic (FiO(2):12.9%) conditions. Electromyographic amplitude, EMG frequency, Oxy(Hb), Deoxy(Hb), Total(Hb), and StO(2) were measured from the vastus lateralis at Initial, 20, 40, 60, 80, and 100% of the repetitions to failure. RESULTS: There was no significant difference in the patterns of responses for EMG amplitude, Oxy(Hb), or Deoxy(Hb) between Normoxia and Hypoxia. For EMG frequency, Hypoxia was greater than Normoxia and decreased with fatigue. Total(Hb) and StO(2) were greater under Normoxia compared to Hypoxia. The patterns of responses for EMG amplitude, Deoxy(Hb), and Total(Hb) increased throughout the repetitions to failure. Oxy(Hb) and StO(2) exhibited decreases throughout the repetitions to failure for Normoxic and Hypoxic conditions. CONCLUSION: The EMG and oxygenation measurements non-invasively suggest a sympathoexcitatory response (indicated by EMG frequency) and provided complimentary information regarding the process of fatigue in normoxic and hypoxic states.
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spelling pubmed-99761812023-03-02 Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions Smith, Cory M. Salmon, Owen F. Jenkins, Jasmin R. J Musculoskelet Neuronal Interact Original Article OBJECTIVES: This study examined effects of acute hypoxia on the neuromuscular responses (electromyographic (EMG) amplitude and EMG frequency) and localized muscle tissue oxygenated hemoglobin (oxygenated hemoglobin (Oxy(Hb)), deoxygenated hemoglobin (Deoxy(Hb)), total hemoglobin (Total(Hb)), and muscle tissue oxygenation saturation (StO(2)) during the process of fatigue. METHODS: Fifteen male participants (21.4±2.8yr) performed leg extension repetitions to failure at 70% 1-repetition maximum until volitional exhaustion under Normoxic (FiO(2):21%) and Hypoxic (FiO(2):12.9%) conditions. Electromyographic amplitude, EMG frequency, Oxy(Hb), Deoxy(Hb), Total(Hb), and StO(2) were measured from the vastus lateralis at Initial, 20, 40, 60, 80, and 100% of the repetitions to failure. RESULTS: There was no significant difference in the patterns of responses for EMG amplitude, Oxy(Hb), or Deoxy(Hb) between Normoxia and Hypoxia. For EMG frequency, Hypoxia was greater than Normoxia and decreased with fatigue. Total(Hb) and StO(2) were greater under Normoxia compared to Hypoxia. The patterns of responses for EMG amplitude, Deoxy(Hb), and Total(Hb) increased throughout the repetitions to failure. Oxy(Hb) and StO(2) exhibited decreases throughout the repetitions to failure for Normoxic and Hypoxic conditions. CONCLUSION: The EMG and oxygenation measurements non-invasively suggest a sympathoexcitatory response (indicated by EMG frequency) and provided complimentary information regarding the process of fatigue in normoxic and hypoxic states. International Society of Musculoskeletal and Neuronal Interactions 2023 /pmc/articles/PMC9976181/ /pubmed/36856097 Text en Copyright: © Journal of Musculoskeletal and Neuronal Interactions https://creativecommons.org/licenses/by-nc-sa/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution-Noncommercial-Share Alike 4.0 Unported, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
spellingShingle Original Article
Smith, Cory M.
Salmon, Owen F.
Jenkins, Jasmin R.
Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title_full Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title_fullStr Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title_full_unstemmed Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title_short Neuromuscular and Muscle Tissue Hemodynamic Responses When Exposed to Normobaric Hypoxia during Lower-Body Fatiguing Muscle Actions
title_sort neuromuscular and muscle tissue hemodynamic responses when exposed to normobaric hypoxia during lower-body fatiguing muscle actions
topic Original Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9976181/
https://www.ncbi.nlm.nih.gov/pubmed/36856097
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