Abstract
Purpose: To investigate the effects of blood flow restriction (BFR) on electromyographic amplitude (EMGRMS)–force relationships of the biceps brachii (BB) during a single high-load muscle action. Methods: Twelve recreationally active males and eleven recreationally active females performed maximal voluntary contractions (MVCs), followed by an isometric trapezoidal muscle action of the elbow flexors at 70% MVC. Surface EMG was recorded from the BB during BFR and control (CON) visits. For BFR, cuff pressure was 60% of the pressure required to completely occlude blood at rest. Individual b (slope) and a terms (gain) were calculated from the log-transformed EMGRMS–force relationships during the linearly increasing and decreasing segments of the trapezoid. EMGRMS during the steady force segment was normalized to MVC EMGRMS. Results: For BFR, the b terms were greater during the linearly increasing segment than the linearly decreasing segment (p < 0.001), and compared to the linearly increasing segment for CON (p < 0.001). The a terms for BFR were greater during the linearly decreasing than linearly increasing segment (p = 0.028). Steady force N-EMGRMS was greater for BFR than CON collapsed across sex (p = 0.041). Conclusion: BFR likely elicited additional recruitment of higher threshold motor units during the linearly increasing- and steady force-segment. The differences between activation and deactivation strategies were only observed with BFR, such as the b terms decreased and the a terms increased for the linearly decreasing segment in comparison to the increasing segment. However, EMGRMS–force relationships during the linearly increasing- and decreasing-segments were not different between sexes during BFR and CON.
Original language | English |
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Pages (from-to) | 1807-1820 |
Number of pages | 14 |
Journal | European Journal of Applied Physiology |
Volume | 124 |
Issue number | 6 |
DOIs | |
State | Accepted/In press - 2024 |
Bibliographical note
Publisher Copyright:© 2024, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Keywords
- Biceps brachii
- Blood flow restriction
- Electromyography
- Motor unit control strategies
ASJC Scopus subject areas
- Orthopedics and Sports Medicine
- Public Health, Environmental and Occupational Health
- Physiology (medical)