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Slope walking causes short-term changes in soleus H-reflex excitability

The purpose of this study was to test the hypothesis that downslope treadmill walking decreases spinal excitability. Soleus H-reflexes were measured in sixteen adults on 3 days. Measurements were taken before and twice after 20 min of treadmill walking at 2.5 mph (starting at 10 and 45 min post). Pa...

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Autores principales: Sabatier, Manning J, Wedewer, Wesley, Barton, Ben, Henderson, Eric, Murphy, John T, Ou, Kar
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BlackWell Publishing Ltd 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4393150/
https://www.ncbi.nlm.nih.gov/pubmed/25742955
http://dx.doi.org/10.14814/phy2.12308
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author Sabatier, Manning J
Wedewer, Wesley
Barton, Ben
Henderson, Eric
Murphy, John T
Ou, Kar
author_facet Sabatier, Manning J
Wedewer, Wesley
Barton, Ben
Henderson, Eric
Murphy, John T
Ou, Kar
author_sort Sabatier, Manning J
collection PubMed
description The purpose of this study was to test the hypothesis that downslope treadmill walking decreases spinal excitability. Soleus H-reflexes were measured in sixteen adults on 3 days. Measurements were taken before and twice after 20 min of treadmill walking at 2.5 mph (starting at 10 and 45 min post). Participants walked on a different slope each day [level (Lv), upslope (Us) or downslope (Ds)]. The tibial nerve was electrically stimulated with a range of intensities to construct the M-response and H-reflex curves. Maximum evoked responses (H(max) and M(max)) and slopes of the ascending limbs (Hslp and Mslp) of the curves were evaluated. Rate-dependent depression (RDD) was measured as the % depression of the H-reflex when measured at a rate of 1.0 Hz versus 0.1 Hz. Heart rate (HR), blood pressure (BP), and ratings of perceived exertion (RPE) were measured during walking. Ds and Lv walking reduced the H(max)/M(max) ratio (P = 0.001 & P = 0.02), although the reduction was larger for Ds walking (29.3 ± 6.2% vs. 6.8 ± 5.2%, P = 0.02). The reduction associated with Ds walking was correlated with physical activity level as measured via questionnaire (r = −0.52, P = 0.04). Us walking caused an increase in the Hslp/Mslp ratio (P = 0.03) and a decrease in RDD (P = 0.04). These changes recovered by 45 min. Exercise HR and BP were highest during Us walking. RPE was greater during Ds and Us walking compared to Lv walking, but did not exceed “Fairly light” for Ds walking. In conclusion, in healthy adults treadmill walking has a short-term effect on soleus H-reflex excitability that is determined by the slope of the treadmill surface.
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spelling pubmed-43931502015-04-20 Slope walking causes short-term changes in soleus H-reflex excitability Sabatier, Manning J Wedewer, Wesley Barton, Ben Henderson, Eric Murphy, John T Ou, Kar Physiol Rep Original Research The purpose of this study was to test the hypothesis that downslope treadmill walking decreases spinal excitability. Soleus H-reflexes were measured in sixteen adults on 3 days. Measurements were taken before and twice after 20 min of treadmill walking at 2.5 mph (starting at 10 and 45 min post). Participants walked on a different slope each day [level (Lv), upslope (Us) or downslope (Ds)]. The tibial nerve was electrically stimulated with a range of intensities to construct the M-response and H-reflex curves. Maximum evoked responses (H(max) and M(max)) and slopes of the ascending limbs (Hslp and Mslp) of the curves were evaluated. Rate-dependent depression (RDD) was measured as the % depression of the H-reflex when measured at a rate of 1.0 Hz versus 0.1 Hz. Heart rate (HR), blood pressure (BP), and ratings of perceived exertion (RPE) were measured during walking. Ds and Lv walking reduced the H(max)/M(max) ratio (P = 0.001 & P = 0.02), although the reduction was larger for Ds walking (29.3 ± 6.2% vs. 6.8 ± 5.2%, P = 0.02). The reduction associated with Ds walking was correlated with physical activity level as measured via questionnaire (r = −0.52, P = 0.04). Us walking caused an increase in the Hslp/Mslp ratio (P = 0.03) and a decrease in RDD (P = 0.04). These changes recovered by 45 min. Exercise HR and BP were highest during Us walking. RPE was greater during Ds and Us walking compared to Lv walking, but did not exceed “Fairly light” for Ds walking. In conclusion, in healthy adults treadmill walking has a short-term effect on soleus H-reflex excitability that is determined by the slope of the treadmill surface. BlackWell Publishing Ltd 2015-03-05 /pmc/articles/PMC4393150/ /pubmed/25742955 http://dx.doi.org/10.14814/phy2.12308 Text en © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society. http://creativecommons.org/licenses/by/4.0/ This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Original Research
Sabatier, Manning J
Wedewer, Wesley
Barton, Ben
Henderson, Eric
Murphy, John T
Ou, Kar
Slope walking causes short-term changes in soleus H-reflex excitability
title Slope walking causes short-term changes in soleus H-reflex excitability
title_full Slope walking causes short-term changes in soleus H-reflex excitability
title_fullStr Slope walking causes short-term changes in soleus H-reflex excitability
title_full_unstemmed Slope walking causes short-term changes in soleus H-reflex excitability
title_short Slope walking causes short-term changes in soleus H-reflex excitability
title_sort slope walking causes short-term changes in soleus h-reflex excitability
topic Original Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4393150/
https://www.ncbi.nlm.nih.gov/pubmed/25742955
http://dx.doi.org/10.14814/phy2.12308
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