Blood flow restriction attenuates surface mechanomyography lateral and longitudinal, but not transverse oscillations during fatiguing exercise

Ethan C Hill; Chris E Proppe; Paola M Rivera; Sean M Lubiak; David H Gonzalez Rojas; John E Lawson; Hwan Choi; Hansen Mansy; Joshua L Keller

doi:10.1088/1361-6579/ad360b

Blood flow restriction attenuates surface mechanomyography lateral and longitudinal, but not transverse oscillations during fatiguing exercise

Physiol Meas. 2024 Apr 9;45(4). doi: 10.1088/1361-6579/ad360b.

Authors

Ethan C Hill^{1

2

3}, Chris E Proppe¹, Paola M Rivera¹, Sean M Lubiak¹, David H Gonzalez Rojas¹, John E Lawson¹, Hwan Choi⁴, Hansen Mansy⁴, Joshua L Keller^{5

6}

Affiliations

¹ School of Kinesiology & Rehabilitation Sciences, University of Central Florida, Orlando, FL 32816, United States of America.
² Florida Space Institute, Partnership I, Research Parkway, University of Central Florida, Orlando, FL 32826, United States of America.
³ College of Medicine, 6850 Lake Nona Blvd, University of Central Florida, Orlando, FL 32827, United States of America.
⁴ College of Engineering, Mechanical and Aerospace, 4328 Scorpius St, University of Central Florida, Orlando, FL 32816, United States of America.
⁵ College of Education and Professional Studies, University of South Alabama, Mobile, AL 36618, United States of America.
⁶ College of Medicine, Department of Physiology and Cell Biology, University of South Alabama, Mobile, AL 36618, United States of America.

PMID: 38507792
DOI: 10.1088/1361-6579/ad360b

Abstract

Objective. Surface mechanomyography (sMMG) can measure oscillations of the activated muscle fibers in three axes (i.e.X,Y, andZ-axes) and has been used to describe motor unit activation patterns (X-axis). The application of blood flow restriction (BFR) is common in exercise studies, but the cuff may restrict muscle fiber oscillations. Therefore, the purpose of this investigation was to examine the acute effects of submaximal, fatiguing exercise with and without BFR on sMMG amplitude in theX,Y, andZ-axes among female participants.Approach. Sixteen females (21 ± 1 years) performed two separate exercise bouts to volitional exhaustion that consisted of unilateral, submaximal (50% maximal voluntary isometric contraction [MVIC]) intermittent, isometric, leg extensions with and without BFR. sMMG was recorded and examined across percent time to exhaustion (%TTE) in 20% increments. Separate 2-way repeated measures ANOVA models were constructed: (condition [BFR, non-BFR]) × (time [20, 40, 60, 80, and 100% TTE]) to examine absolute (m·s^-2) and normalized (% of pretest MVIC) sMMG amplitude in theX-(sMMG-X),Y-(sMMG-Y), andZ-(sMMG-Z) axes.Main results. The absolute sMMG-X amplitude responses were attenuated with the application of BFR (mean ± SD = 0.236 ± 0.138 m·s^-2) relative to non-BFR (0.366 ± 0.199 m·s^-2, collapsed across time) and for sMMG-Y amplitude at 60%-100% of TTE (BFR range = 0.213-0.232 m·s^-2versus non-BFR = 0.313-0.445 m·s^-2). Normalizing sMMG to pretest MVIC removed most, but not all the attenuation which was still evident for sMMG-Y amplitude at 100% of TTE between BFR (72.9 ± 47.2%) and non-BFR (98.9 ± 53.1%). Interestingly, sMMG-Z amplitude was not affected by the application of BFR and progressively decreased across %TTE (0.332 ± 0.167 m·s^-2to 0.219 ± 0.104 m·s^-2, collapsed across condition.)Significance. The application of BFR attenuated sMMG-X and sMMG-Y amplitude, although normalizing sMMG removed most of this attenuation. Unlike theXandY-axes, sMMG-Z amplitude was not affected by BFR and progressively decreased across each exercise bout potentially tracking the development of muscle fatigue.

Keywords: BFR; MMG; fatigue; occlusion; women.

Creative Commons Attribution license.

MeSH terms

Electromyography
Exercise / physiology
Female
Humans
Isometric Contraction / physiology
Muscle Fatigue* / physiology
Muscle, Skeletal / physiology
Physical Therapy Modalities
Regional Blood Flow
Resistance Training* / methods