Human Integrative Physiology Laboratory, School of Business Administration, Meiji University, Tokyo, Japan.
Eur J Appl Physiol. 2014 Mar;114(3):451-65. doi: 10.1007/s00421-013-2691-y. Epub 2013 Jul 12.
During high-intensity dynamic exercise, O2 delivery to active skeletal muscles is enhanced through marked increases in both cardiac output and skeletal muscle blood flow. When the musculature is vigorously engaged in exercise, the human heart lacks the pumping capacity to meet the blood flow demands of both the skeletal muscles and other organs such as the brain. Vasoconstriction must therefore be induced through activation of sympathetic nervous activity to maintain blood flow to the brain and to produce the added driving pressure needed to increase flow to the skeletal muscles. In this review, we first briefly summarize the local vascular and neural control mechanisms operating during high-intensity exercise. This is followed by a review of the major neural mechanisms regulating blood pressure during high-intensity exercise, focusing mainly on the integrated activities of the arterial baroreflex and muscle metaboreflex. In high cardiac output situations, such as during high-intensity dynamic exercise, small changes in total peripheral resistance can induce large changes in blood pressure, which means that rapid and fine regulation is necessary to avoid unacceptable drops in blood pressure. To accomplish this rapid regulation, arterial baroreflex function may be modulated in various ways through activation of the muscle metaboreflex and/or other neural mechanisms. Moreover, this modulation of the arterial baroreflex may change over the time course of an exercise bout, or to accommodate changes in exercise intensity. Within this model, integration of arterial baroreflex modulation with other neural mechanisms plays an important role in cardiovascular control during high-intensity exercise.
在高强度动态运动中，通过心输出量和骨骼肌血流量的显著增加，向活跃的骨骼肌输送氧气。当肌肉剧烈运动时，人类的心脏缺乏足够的泵血能力来满足骨骼肌和大脑等其他器官的血液需求。因此，必须通过激活交感神经系统来引起血管收缩，以维持大脑的血液流动，并产生增加流向骨骼肌所需的附加驱动力。在这篇综述中，我们首先简要总结了高强度运动期间起作用的局部血管和神经控制机制。接着，我们回顾了调节高强度运动期间血压的主要神经机制，主要集中在动脉压力反射和肌肉代谢反射的综合活动上。在高心输出量的情况下，例如在高强度动态运动中，总外周阻力的微小变化可引起血压的大幅变化，这意味着需要快速和精细的调节，以避免血压不可接受的下降。为了实现这种快速调节，动脉压力反射功能可以通过肌肉代谢反射和/或其他神经机制的激活以各种方式进行调节。此外，动脉压力反射的这种调节可能会随着运动的时间进程而改变，或者适应运动强度的变化。在这个模型中，动脉压力反射调节与其他神经机制的整合在高强度运动期间的心血管控制中起着重要作用。
