Cerebral cortex activation and functional connectivity during low-load resistance training with blood flow restriction: An fNIRS study

• Published in: PloS one Vol. 19; no. 5; p. e0303983
• Main Authors: Jia, Binbin, Lv, Chennan, Li, Danyang, Lv, Wangang
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 23.05.2024; Public Library of Science (PLoS)
• Subjects: Adult; Biology and Life Sciences; Blood flow; Brain; Brain research; Cerebral cortex; Cerebral Cortex - blood supply; Cerebral Cortex - diagnostic imaging; Cerebral Cortex - metabolism; Cerebral Cortex - physiology; Cerebrum; Consent; Cortex (motor); Electromyography; Experiments; Hemoglobin; Humans; Hypertrophy; Hypotheses; Infrared imaging systems; Load resistance; Male; Medicine and Health Sciences; Metabolism; Motor Cortex - diagnostic imaging; Motor Cortex - physiology; Neural networks; Neurophysiology; Physical Sciences; Physical training; Prefrontal cortex; Prefrontal Cortex - blood supply; Prefrontal Cortex - diagnostic imaging; Prefrontal Cortex - metabolism; Prefrontal Cortex - physiology; Pressure effects; Resistance training; Resistance Training - methods; Sensors; Spectroscopy, Near-Infrared - methods; Strength training; Supplementary motor area; Weight training; Young Adult; United States > US
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0303983

Despite accumulating evidence that blood flow restriction (BFR) training promotes muscle hypertrophy and strength gain, the underlying neurophysiological mechanisms have rarely been explored. The primary goal of this study is to investigate characteristics of cerebral cortex activity during BFR training under different pressure intensities. 24 males participated in 30% 1RM squat exercise, changes in oxygenated hemoglobin concentration (HbO) in the primary motor cortex (M1), pre-motor cortex (PMC), supplementary motor area (SMA), and dorsolateral prefrontal cortex (DLPFC), were measured by fNIRS. The results showed that HbO increased from 0 mmHg (non-BFR) to 250 mmHg but dropped sharply under 350 mmHg pressure intensity. In addition, HbO and functional connectivity were higher in M1 and PMC-SMA than in DLPFC. Moreover, the significant interaction effect between pressure intensity and ROI for HbO revealed that the regulation of cerebral cortex during BFR training was more pronounced in M1 and PMC-SMA than in DLPFC. In conclusion, low-load resistance training with BFR triggers acute responses in the cerebral cortex, and moderate pressure intensity achieves optimal neural benefits in enhancing cortical activation. M1 and PMC-SMA play crucial roles during BFR training through activation and functional connectivity regulation.