Gomez Manuel, Montalvo Samuel, Sanchez Alejandro, Conde Daniel, Ibarra-Mejia Gabriel, Peñailillo Luis E, Gurovich Alvaro N
The University of Texas at El Paso.
Stanford University School of Medicine.
Res Q Exerc Sport. 2025 Jun;96(2):287-297. doi: 10.1080/02701367.2024.2404139. Epub 2024 Sep 20.
Eccentric exercise has gained attention as a novel exercise modality that increases muscle performance at a lower metabolic demand. However, vascular responses to eccentric cycling (ECC) are unknown, thus gaining knowledge regarding endothelial shear stress (ESS) during ECC may be crucial for its application in patients. The purpose of this study was to explore ECC-induced blood flow patterns and ESS across three different intensities in ECC. Eighteen young, apparently healthy subjects were recruited for two laboratory visits. Maximum oxygen consumption, power output, and blood lactate (BLa) threshold were measured to determine workload intensities. Blood flow patterns in the brachial artery were measured via ultrasound imaging and Doppler on an eccentric ergometer during a 5 min workload steady exercise test at low (BLa of 0-2 mmol/L), moderate (BLa 2-4 mmol/L), and high intensity (BLa levels > 4 mmol/L). There was a significant increase in the antegrade ESS in an intensity-dependent manner (baseline: 44.2 ± 8.97; low: 55.6 ± 15.2; moderate: 56.0 ± 10.5; high: 70.7 ± 14.9, all dynes/cm2, all values < 0.0002) with the exception between low and moderate and Re (AU) showed turbulent flow at all intensities. Regarding retrograde flow, ESS also increased in an intensity-dependent manner (baseline 9.72 ± 4.38; low: 12.5 ± 3.93; moderate: 15.8 ± 5.45; high: 15.7 ± 6.55, all dynes/cm2, all values < 0.015) with the exception between high and moderate and Re (AU) showed laminar flow in all intensities. ECC produced exercise-induced blood flow patterns that are intensity-dependent. This suggests that ECC could be beneficial as a modulator of endothelial homeostasis.
离心运动作为一种新型运动方式已受到关注，它能以较低的代谢需求提高肌肉性能。然而，血管对离心骑行（ECC）的反应尚不清楚，因此了解ECC期间的内皮剪切应力（ESS）对于其在患者中的应用可能至关重要。本研究的目的是探讨ECC在三种不同强度下引起的血流模式和ESS。招募了18名年轻、看似健康的受试者进行两次实验室检查。测量最大耗氧量、功率输出和血乳酸（BLa）阈值以确定工作负荷强度。在低强度（BLa为0 - 2 mmol/L）、中等强度（BLa为2 - 4 mmol/L）和高强度（BLa水平> 4 mmol/L）的5分钟工作负荷稳定运动测试期间，通过超声成像和多普勒在离心测力计上测量肱动脉的血流模式。顺行ESS以强度依赖的方式显著增加（基线：44.2±8.97；低强度：55.6±15.2；中等强度：56.0±10.5；高强度：70.7±14.9，单位均为达因/平方厘米，所有P值<0.0002），低强度和中等强度之间除外，且雷诺数（AU）在所有强度下均显示湍流。关于逆行血流，ESS也以强度依赖的方式增加（基线9.72±4.38；低强度：12.5±3.93；中等强度：15.8±5.45；高强度：15.7±6.55，单位均为达因/平方厘米，所有P值<0.015），高强度和中等强度之间除外，且雷诺数（AU）在所有强度下均显示层流。ECC产生了强度依赖的运动诱导血流模式。这表明ECC作为内皮稳态的调节剂可能是有益的。
