Open AccessEffect of an inverted seated position with upper arm blood flow restriction on measures of elbow flexors neuromuscular performance
Author(s) -
Hamid Ahmadi,
Nehara Herat,
Shahab Alizadeh,
Duane C. Button,
Urs Granacher,
David G. Behm
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0245311
Subject(s) - algorithm , medicine , computer science
Purpose The objective of the investigation was to determine the concomitant effects of upper arm blood flow restriction (BFR) and inversion on elbow flexors neuromuscular responses. Methods Randomly allocated, 13 volunteers performed four conditions in a within-subject design: rest (control, 1-min upright position without BFR), control (1-min upright with BFR), 1-min inverted (without BFR), and 1-min inverted with BFR. Evoked and voluntary contractile properties, before, during and after a 30-s maximum voluntary contraction (MVC) exercise intervention were examined as well as pain scale. Results Inversion induced significant pre-exercise intervention decreases in elbow flexors MVC (21.1%,η p 2= 0.48, p = 0.02) and resting evoked twitch forces (29.4%,η p 2= 0.34, p = 0.03). The 30-s MVC induced significantly greater pre- to post-test decreases in potentiated twitch force (η p 2= 0.61, p = 0.0009) during inversion (↓75%) than upright (↓65.3%) conditions. Overall, BFR decreased MVC force 4.8% (η p 2= 0.37, p = 0.05). For upright position, BFR induced 21.0% reductions in M-wave amplitude (η p 2= 0.44, p = 0.04). There were no significant differences for electromyographic activity or voluntary activation as measured with the interpolated twitch technique. For all conditions, there was a significant increase in pain scale between the 40–60 s intervals and post-30-s MVC (upright