Multiple Comparisons in Different ROI (HbO_max).

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.尽管已有大量研究证据表明，血流限制训练（blood flow restriction, BFR）可促进肌肉肥大与力量增长，但其潜在的神经生理机制却极少被探索。本研究的首要目标为探究不同压力强度下，血流限制训练过程中大脑皮层的活动特征。招募24名男性受试者完成30%1RM负荷的深蹲练习，采用功能性近红外光谱（fNIRS）检测了初级运动皮层（M1）、前运动皮层（PMC）、辅助运动区（SMA）及背外侧前额叶皮层（DLPFC）的氧合血红蛋白浓度（HbO）变化。结果显示，HbO水平随压力从0 mmHg（无BFR干预）升至250 mmHg时逐渐升高，但在350 mmHg压力强度下出现显著下降。此外，M1以及PMC-SMA通路的HbO水平与功能连接均高于DLPFC。进一步分析发现，压力强度与感兴趣区（Region of Interest, ROI）对HbO的交互效应显著，提示血流限制训练过程中大脑皮层的调控作用在M1与PMC-SMA通路中较DLPFC更为突出。综上，伴随血流限制的低负荷抗阻训练可诱发大脑皮层的急性响应，且中等压力强度可实现最优的神经益处，以增强皮层激活。M1与PMC-SMA通路可通过激活及功能连接调控，在血流限制训练中发挥关键作用。