Department of Kinesiology, University of Alabama, Tuscaloosa, Alabama, USA.
Department of Educational and Psychological Studies, College of Education, University of South Florida, Tampa, Florida, USA.
Clin Physiol Funct Imaging. 2024 Jul;44(4):285-296. doi: 10.1111/cpf.12873. Epub 2024 Feb 24.
This study was conducted to investigate the systemic hemodynamic and vascular changes in women during and after two commonly used clinical blood flow restriction (BFR) pressures at rest. There are minimal data regarding the independent effects of BFR on hemodynamic and systemic vascular changes due to pressor response, particularly among women. Therefore, this study investigated BFR-induced alterations in pressor response and systemic flow redistribution at rest during two commonly used pressures (50% and 80% limb occlusion pressure [LOP]). Fifteen women (22.1 ± 4.2 years) completed two randomised sessions involving 8-min of bilateral, lower limb restriction at 50% or 80% LOP followed by 8-min of recovery post-deflation. Changes in vascular (arterial diameter [DIA], time-averaged mean velocity [TAMV], volume flow [VF], and area) and hemodynamic (heart rate [HR] and blood pressure) measures over time (pre-, during, post-occlusion) and by session (50% vs. 80% LOP) were tested using repeated measures analysis of variance. Repeated measures correlations (r) quantified common intraindividual associations between BFR-induced hemodynamic and vascular responses. HR increased from baseline during 50% LOP and remained elevated during recovery (p < 0.05). HR increased from baseline during 80% LOP, while tibial VF and TAMV decreased (p < 0.03 for all). HR and TAMV values returned to baseline during recovery, while brachial artery VF decreased (p < 0.05). Changes in HR, brachial VF, and brachial TAMV were similar between 50% and 80% LOP (r = 0.32-0.70, p < 0.05 for all). At 80% LOP, changes in HR were positively correlated with brachial VF (r = 0.38) and TAMV (r = 0.43) and negatively correlated with tibial VF (r = -0.36) and TAMV (r = -0.30) (p < 0.05 for all). Results suggest that BFR at 80% LOP elicits an acute systemic pressor reflex without concomitant increases in brachial arterial flow, while 50% LOP elicits a subdued response.
本研究旨在探究两种常用临床血流限制（BFR）压力下女性的全身血液动力学和血管变化。由于加压反应，BFR 对血流动力学和全身血管变化的独立影响的数据很少，特别是在女性中。因此，本研究调查了在两种常用压力（50%和 80%肢体闭塞压力[LOP]）下，BFR 诱导的加压反应和全身血流再分布的变化。15 名女性（22.1±4.2 岁）完成了两次随机试验，包括 8 分钟的双侧下肢限制，分别为 50%或 80%LOP，然后在放气后 8 分钟恢复。使用重复测量方差分析测试了血管（动脉直径[DIA]、时间平均流速[TAMV]、体积流量[VF]和面积）和血液动力学（心率[HR]和血压）随时间（预、中、后闭塞）和试验（50%与 80%LOP）的变化。重复测量相关系数（r）量化了 BFR 诱导的血液动力学和血管反应之间的个体内常见关联。HR 在 50%LOP 期间从基线增加，并在恢复期间保持升高（p<0.05）。HR 在 80%LOP 期间从基线增加，而胫骨 VF 和 TAMV 降低（p<0.03 所有）。HR 和 TAMV 值在恢复期间恢复到基线，而肱动脉 VF 降低（p<0.05）。50%和 80%LOP 之间的 HR、肱动脉 VF 和肱动脉 TAMV 变化相似（r=0.32-0.70，p<0.05 所有）。在 80%LOP 下，HR 的变化与肱动脉 VF（r=0.38）和 TAMV（r=0.43）呈正相关，与胫骨 VF（r=-0.36）和 TAMV（r=-0.30）呈负相关（p<0.05 所有）。结果表明，80%LOP 时的 BFR 会引起急性全身加压反射，而不会同时增加肱动脉血流，而 50%LOP 则会引起较弱的反应。
